* GB785999 (A)

Description: GB785999 (A) ? 1957-11-06

Process for bleaching waxes, fatty oils and fats

Description of GB785999 (A)

PATENT SPECIFICATION Inventors: ROBERT SCHIRMER, HEINRICH VOIT and HANS HOYER -: 7859999 Date of Application and filing Complete Specification Sept I, 1955. No 25194/55. Complete Specification Published Nov 6,1957. Index at acceptance: -Class 91, C 2 A( 1: 2), W 4. International Classification: -Cilb. COMPLETE SPECIFICATION Process for heachiing Waxes, Fatty O Iii Rs aind Fats We, FARBWERME T-OECHST Al T'IENGESELLSCHAFT vorinals Meister Lucius & Brining, a Body Corporate recognised under German Law, of Frankfurt (M)-Hoechst, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention relates to a process for bleaching waxes, fatty oils and fats. It is known to bleach wax by mixing it with an oxidising agent (bleaching agent) for example chromosulphuric acid, in a vessel provided with a stirrer In this vessel the material to be bleached is mixed with the bleaching agent and there are also carried out the chemical part of the bleaching process and the separation of the bleached material from the bleaching agent It is also known to carry out the bleaching in stages, the chemical part of the bleaching process being divided into two or perhaps more stages When a relatively large number of stages is employed, however, the above process is no longer economical. According to another known process, the oxidising agent flows continuously through a vessel of the type above mentioned and is then

conducted in a cycle for regeneration and returned to the vessel It has also been proposed to carry out the bleaching in such a vessel by pre-oxidising the material to be bleached and then causing it and the bleaching agent to flow together through the apparatus in a continuous manner but in counter-current to one another This process is very difficult to carry out in practice since increased formation of foam either greatly impedes the counter-current when the latter is conducted vertically, or requires an apparatus of excessively large base when the counter-current movement takes place horizontally Apart from this process, the known method of bleaching wax is, as far as the material to be bleached is concerned, a discontinuous one. lPric Furthermore, the known methods involve the following drawbacks:It is impossible or only possible to a very restricted extent to maintain the most favourable conditions in different stages of the bleaching process, for example certain values of reaction temperature and a certain concentration of bleaching agent Especially in the first stage of the bleaching process, before the material to be bleached and the bleaching agent separate from one another automatically due to difference in density, in which stage, howvever, uhe major part of the chemical reactions takes place, it is impossible to control the reaction in a desired manner since, for example, the concentration of the bleaching agent cannot be varied in any desired manner. In the first stage some of the particles of the material to be bleached are already attacked by the bleaching agent while others have not yet been attacked; the most favourable concentration of bleaching agent for each particular particle depends upon the degree to which this particle is attacked; since, however, the bleaching agent can only be present in the reaction mixture in a uniform concentration it cannot be avoided that the concentration, while it is most advantageous for bleaching some of the particles, is little favourable for other ones. Conscquently, it is Impossible specifically to adjust the reaction conditions to every particle. Furthermore, the gases and vapours which are formed during the bleaching process, especially carbon dioxide and water vapour, give rise to an increased formation of foam, The vessel equipped with a stirrer must therefore be very large as compared with the quantity of the wax to be bleached. Moreover, the time required for charging, discharging and cleaning the vessel and also for separating the bleached material from the bleaching agent, is relatively long compared with that required for the bleaching itself. Furthermore, towards the end of the ( 6 so bleaching process the

material to be bleached and the bleaching agent scarcely mix with one another without great expenditure ol mechanical energy, so that the last phase of bleaching requires a very long time. -the present invention is based on the observation that the above mentioned drawbacks can be avoided and waxes, ratty oils and tats can be bleached with chromosulphuric acid in a simple and suitable manner by subdividing the total bleaching process into several separate stages, separating the material being bleached and the bleaching agent from one another, after each stage, agam mixing tihe separated material, to be further bleached in a later stage, with a bleaching agent, which may be fresh or already used in the present process, and continuously conducting the material to be bleached and the bleaching agent in co-current in each individual stage. It is sufficient to carry out the said separations according to such methods as are usual in industry. When waxes are bleached with aqueous oxidising media, the following chemical reactions primarily take place:1) Impurities, such as resins and acids containing hydroxyl groups, are oxidised to a large extent and mainly decomposed to carbon dioxide and water. 2) The esters which constitute the main fraction of the material to be bleached, are saponified to the corresponding fatty acids and alcohols with consumption of water. 3) The alcohols which have been formed as described under 2) are oxidised to the corresponding fatty acids with simultaneous formation of water. 4) The fatty acids which have been formed as described under 2) and 3) are partly decomposed by the bleaching agent with formation of fatty acids having shorter hydrocarbon chains; this process is undesirable and should be avoided as tar as possible. Although the sequence is as set forth above, the individual processes in part overlap one another in the total bleaching process When in the case of the partial process of one of the above four stages, the mass of the substance d S formed per unit of time (S=mass of the substance formed, t=time) is plotted as ordinate and the time as abscissa, the curve obtained always first rises from the origin, reaches a maximum value-unless the process is stopped prematurely-and falls again to zero The curves of the partial processes of the individual stages are related one to another and also depend upon the composition of the mixture of the material to be bleached and the bleaching agent and upon external influences such as temperature and pressure The nature of each of the curves can be separately changed when the material to be bleached and the bleaching agent are conducted continuously in the same direction according to 65 this invention. The process according to the present invention is carried out in at

least two, advantageously in 3 reaction stages It is, however, also possible to provide more stages, for 70 Lxampie 6, aithough too large a number oi stages renders the process more complicate. The external factors influencing the progress of the reaction such as temperature and pressure, can thus be adjusted as required at each 75 part of the apparatus By the application of superatmospheric pressure it is even possible to raise the reaction temperature in certain parts of the apparatus above the boiling point at normal atmospheric pressure of the mixture So of the material to be bleached and the bleaching agent In order to be able to vary the composition of the mixture of tne bleaching agent and the material to be bleached, the total bleaching process must be divided up into 85 stages corresponding to separate partial processes, each stage comprising a process of mixing, a process of reaction and a process of separating the material to be bleached from the bleaching agent 90 In carrying out the process of the invention, the various stages are each conducted in an allotted section of the apparatus, the material to be bleached and the bleaching agent always being conducted in the same direction It is 95 also possible to modify one or more stages by adding bleaching agents at different places in the sections corresponding to the individual stages it is obviously not always possible to arrange for the whole of a particular reaction 100 to take place in any particular section but one reaction may commence at a point in one section, proceed through the whole of the next section and perhaps be completed in a third section Each process of separation is advan 105 tageously carried out at the same place in the apparatus so that the used bleaching agent can be replaced by a fresh one for use in the next section In this manner, the composition of the bleaching agent, the quantitative propor 110 tion between the material to be bleached and the bleaching agent and therefore the composition of the material being bleached can be varied. An apparatus suitable for use in carrying 115 out the process of this invention is illustrated diagrammatically by way of example in the accompanying drawings. Referring to the drawings, a section comprises a mixing device 1, a reactor 2 and a 120 separating device 3 (see Fig I) The bleaching agent is introduced at 4, the material to be bleached at 5; the latter can be removed at 6 and the former at 7 Reactor 2 may, for example, consist of a tube system; if desired, 125 the pipe connecting the mixing device with the separating device may itself serve as reactor because of the short reaction times which can 785,999 of the reactor 15 and the inlet of the mixing device 16 o O this particular section of the apparatus so that the mixture of the material to De oteacned and the bleaching agent can be recycled several times through this

section. When the mixture of the material to be oleacned and the bleaching agent does not separate automatically, the composition of the said mixture can also be varied by separating the materiai to be bleached and the bleaching agent by mechanical means using an additional device, ror example a separator or centrifuge. When such additional device is used, a return pipe is not necessary tor the particular section out may in some circumstances be of advantage at least a part of one reactant, i e of time material to be bleached or the bleaching agent, or both the reactants together, can be returned, either completely or partially, to the mixing device of the stage concerned even aiter they have been separated. As stated above, within each stage the material to De bleached and the bleaching agent flow in the same direction Through the individual stages, however, the material to be bleached and the bleaching agent can pass in any predetermined succession whereby the quality of the final product can be influenced to a certain degree Fig 3 shows, by way of example, the arrangement of apparatus in the case of 3 stages Conduits for the bleaching agent are indicated at 17, conduits for the material to be bleached at 18 conduits for the mixture of the bleaching agent and the material to be bleached at 19 and conduits for the mixtures of the bleaching agent and the material to be bleached and/or for the bleaching agent and/or for the material to be bleached at 20. The method of conducting the material to be bleached and the bleaching agent in the same direction involves the further particular advantage that the process can take place in a flow apparatus in which a high degree of turbulence can be attained with little expenditure of energy Accordingly the material to be bleached and the bleaching agent can be mixed with one another very intensively The time of reaction is relatively short; it can be further reduced by utilization of a relatively high concentration of the bleaching agent When the total bleaching process is not interrupted, the concentration of the bleaching agent decreases exponentially with time The resulting curve can be divided into a branch representing a vigorous reaction and a branch representing only a very slow reaction Advantageously a stage should correspond only to the former branch, while the latter branch should be avoided as far as possible by separation of the material to be bleached from the bleaching agent When chromosulphuric acid is used, which can be regenerated in an electrolytic cell equipped with a diaphragm, a residual concentration of the chromosulphuric acid in any be obtained by the present process In general, a part of the reaction already takes place in the mixing device before entry into the said pipe With a predetermined number oi stages the most favourable

conditions can be applied, for example, in order to obtain the shortest possible time of reaction or final products o O an especially high quality It is of advantage to provide for the possiblity of varying the following factors:a) Temperature of the material to be bleached flowing to the mixing device concerned; b) Temperature of the bleaching agent flowing to the mixing device concerned; c) Temperature in the reactor concerned; d) Composition of the bleaching agent flowing to the mixing device concerned; e) Ratio of the quantity of the material to be bleached to the quantity of the bleaching agent iowing per unit of time into the mixing device concerned; t) Pressures in the mixing device, the reactor and the separating device concerned. By the process of this invention waxes, fatty oils and fats can be obtained having the specific properties required in each particular case for their intended use The above mentioned most favourable conditions depend on the desired properties of the products and can be determined and applied in each particular case in the practice of the process of the present invention. Mixing device l, reactor 2 and separating device 3, shown diagrammatically in Fig 1, are represented in more detail in Fig 2 In this case a vessel 3 serves as separating device in which the individual components separate owing to their different specific gravities. The bleaching agent is shown at 8, the material to be bleached at 10 and the mixture of the bleaching agent and the material to be bleached at 9 Valves are represented at 11, a pump at 12 and a device for sucking in the mixture 9 at 13. If no particular importance is attached to being able to control the composition of the mixture of the bleaching agent and the material to be bleached before the material to be bleached and the bleaching agent are separated from one another automatically due to their difference in density, it is sufficient to provide vessels 3 through which the bleaching agent and the material to be bleached pass in streamline flow (see Fig 2) When in this case the consequential time of dwell of the mixture of the bleaching agent and the material to be bleached in the reactor of a particular stage is not sufficient for producing the automatic separation of the material to be bleached and the bleaching agent after the mixture has passed through the reactor once, this particular section of the apparatus must be provided with a rettun pipe 14 The latter is an additional connection between the outlet 785,999 785,9 g 9 particular stage involves no disadvantage, since it has been found that between chromosulphuric acid of low concentration and crude wax or slightly bleached wax so strong a reaction takes place that in a desired stage the concentration of the chromosulphuric acid can be reduced to 0 by employing an appropriate proportion of the

constituents of the mixture, which proportion can be easily determined by simple test As indicated above, in the bleaching of crude wax with chromosulphuric acid, gases and vapours, particularly carbon dioxide and water vapour, are forin-d, especially in the first phase of the reaction When the material to be bleached and the bleaching agent are mixed thoroughly, the above mentioned gases are formed almost throughout the mixture The specific properties of this mixture of wax and chromosulphuric acid at reaction temperature, however, prevent an enlargement and the combination of small bubbles and also an escape of the gases and give rise to an increase in the number of bubbles per unit of volume, i e to foam formation In order Lo avoid the formation of too much foam, the reaction has hitherto in most cases been purposely checked, for example by adjusting to a temperature which does not promote the reaction to any great extent, by a relatively low 29 degree of mixing or by a delayed bringing together of the material to be bleached and the bleaching agent On the other hand, relatively large reaction vessels have been used to avoid foaming over. The pellicle of the individual bubbles consists partially of a wax layer and partially of a chromosulphuric acid layer The space between the bubbles is mainly filled with thromosulphuric acid In the state of foam crude wax and chromosulphuric acid have a large surface of contact due to the vesicular structure They are, however, divided into a large number of small volumes This state is maintained until the reaction becomes weaker or subsides When this mixture is in the state of foam-i e primarily in the first phase of the bleaching process in which the chemical reaction would be expected to be most vigorous-the reaction can only continue slowly since the surface at which reactants are in contact with one another is constant, that is, it is not enlarged or diminished in the course of time even if their position in the foam is changed by turbulence. Reaction-promoting diffusion through the boundary surfaces is furthermore impeded by interfacial tensions. It has further been found that these influences of the foam which retard the course of the reaction can be overcome or reduced without preventing the initial formation of the foam, but by destroying it, advantageously by varying the pressure, at least at one place in the complete apparatus, suitably after the reaction mixture has left a particular stage This is a dilferent procedure from the known processes In processes of wax oxidation according to the continuous flow principle, this can be done with the aid of any appropriate mechanical foam destroying means in an early stage 70 of the total bleaching process In this manner the yield of bleached wax per unit of time can be still further increased. It is of advantage to divide the reactor 2, as shown in Fig 4, into

two or more smaller 75 partial reactors, for example 21 and 22, and to arrange between them one or more mechanical foam destroyers, for example 23 and 24, in which, if desired, a part of the reaction may be allowed to take place In this manner, the 80 mixture oi the material to be bleached and the bleaching agent enters each partial reactor after having had the foam destroyed The separating device has itself a foam destroying action but the separation effect can, however, 85 be enhanced by arranging a foam destroying device in front of the separator In the above mentioned process according to which vessels 3 (Pig 2) are used, appropriate foam, removal is also of advantage It is however, of par 90 ticular advantage to enhance the effect of each such vessel, which replaces an ordinary separator, by passing the reaction mixture through a foam destroyer before it enters the separator Fig 5 shows, by way of example, 95 such an arrangement A foam destroyer 23 may suitably comprise a vessel 25 in which fluctuation of pressure is produced, for example, by an oscillating membrane (diaphragrn) 26 which is operated at 27 either 100 mechanically or electrically or by means of a valve control-mechanism with the aid of reaction gas, air or other inert gas The mixture (if the material to be bleached and the bleaching agent enters the foam destroyer 23 at 28 105 and leaves at 29 after having had the foam removed The waste gas is led off at 30 by way of a non-return valve 31 The lower part of Fig 5 is the same as the right hand part of Fig 2 110 For destroying the foam, devices can be used in which the mixture of the material to be bleached and the bleaching agent is subjected to rapidly varying pressures Rotary pumps, centrifugal mixing devices, separating 115 devices or centrifuges have, for example, a destroying action on foam. By the above process there can be bleached solid or liquid waxes, for example montan wax, candelilla wax, ouricouri wax, beeswax, 120 spermaceti, wool wax, carnauba wax, synthetic waxes obtained, for example, by esterification of palmitic or stearic acid with cetyl or octodecyl alcohol, fatty oils and fats such as palm kernel oil, coconut oil, olive oil, cottonseed oil, 125 sesame oil, poppyseed oil, soy bean oil, peanut oil, whale oil or hog fat The process of this invention is especially suitable when the said fats art intended for technical purposes.

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* 5.8.23.4; 93p

* GB786000 (A)

Description: GB786000 (A) ? 1957-11-06

Odour inhibited polyethylene

Description of GB786000 (A)

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PATENT SPECIFICATION 786000 Date of Application and filing Complete Specification: Oct 19, 1955. No 29801155. Application made in United States of America on Oct 21, 1954. Complete Specification Published: Nov 6, 1957. Index at acceptance:-Class 2 ( 6), P 7 C( 8 B: 10: 20 B), P 7 (D 1 A: 52). International Classification:-CO 8 f. COMPLETE SPECIFICATION Odour Inhibited Polyethylene We, UNION CARBIDE CORPORATION (formerly Union Carbide and Carbon Corporation), of 30, East 42nd Street, New York, State of New York, United States of America, a Corporation organised under the laws of the State of New York, United States of America (assignee of JAMES HARDING), do hereby declare the invention,

for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to inhibiting odor development in polyethylene or polyethylene compositions More particularly, the invention relates to the stabilization of polyethylene against objectionable odor development by incorporating in the polyethylene a minor amount of certain monohydric phenols as odor inhibitors. Normally solid polymers of ethylene are well known and widely used in the production of thermoplastic products such as film, sheeting, and molded articles Virgin polyethylene as obtained from the polymerizing equipment is generally practically odorless, but upon extended storage, and especially at elevated temperatures, e g 35 o C -90 ' C, or when subjected to heat required for processing as in extrusion or molding, the polyethylene develops a rancid-like odor The odor intensity, which is somewhat similar in its sharpness to butyric acid, varies according to the exposure conditions, thus it is more intense in closed atmospheres as for example the interior of sealed polyethylene bottles or jars than is the case with polyethylene sheeting used as external wrapping or packaging material However, odor can be readily detected on polyethylene sheeting stored for some time in a closed package Apparently, while polyethylene is regarded as one of the more stable polymers, it nevertheless under conditions of normal usage or heat-processing suffers some slight decomposition sufficient to be detected olfactorily Such odor development has caused consumers to object to articles manufactured (Trice 3 s 6 d l from polyethylene, such as cosmetic jars, bottles, filn or sheeting, particularly when polyethylene comes in contact with foodstuffs. It has now been found that objectionable odor development in polyethylene can be substantially suppressed by incorporating in the polyethylene relatively small amounts of a trialkyl substituted monohydric phenol in which the two ortho positions and the para position contain an allkyl substituent, for example, methyl, ethyl, butyl, amyl, octyl, nonyl, and dodecyl, and free from any substituents other than hydrogen on the two meta positions. Such phenols are represented by the formula: o H R 3 O R, R 2 wherein R 1, R 2, and R, are each the same or a different allyl radical The alkyl radicals may contain from 1 to 12 carbon atoms. Somewhat higher efficiencies in suppressing odor has been observed when R 1 and R, are tertiary alkyl groups instead of normal or secondary alkyl groups and hence such phenols are preferred. Specific phenols within the scope of the above formula and useful in the practice of this invention are the following:

2,4,6-trimethyl phenol 2,4,6-triisopropyl phenol 2,4,6-triethyl phenol 2,4,6-tritertiary butyl phenol 2,4,6-tritertiary amyl phenol 2-tertiary butyl-4,6-dimethyl phenol 2,6-diethyl-4-methyl phenol 2,6-ditertiary butyl-4-methyl phenol 2,6-dipropyl-4-methyl phenol 2,6-diethyl-4-tertiary butyl phenol 2,6-ditertiary butyl-4-tertiary amyl phenol 2,6-dimethyl-4-dodecyl phenol 2,6-ditertiary butyl-4-nonyl phenol PW u 25 p I1 r, E 7 , The discovery that trialkyl substituted phenols of the aforedescribed type are effective in suppressing odor development in polyethylene is considered most surprising in view S of the fact that, while these phenols when freshly prepared are generally characterized by a mild unobjectionable odor, they have been reported as tending to develop an objectionable odor upon storage Thus it has been suggested that alkyl phenols be stabilized against deterioration in odor by treating the phenol with from about 0 01 per cent to 5 per cent by weight of organic polybasic carboxylic acids or salts thereof. For the purposes of the present invention, it is not essential to stabilize the alkyl substituted phenol as suggested; however, if desired, such stabilized phenols can be employed for incorporation in polyethylene. Incorporation in polyethylene of amounts as little as 0 005 per cent by weight of a 2,4,6-trialkyl substituted phenol has been found effective in suppressing or minimizing odor development in polyethylene Preferably, there are employed amounts of trialkyl substituted phenol between 0 001 per cent to 0 02 per cent by weight of the polyethylene, since within this range satisfactory inhibition of the odor normally developed in uninhibited polyethylene is prevented over extended periods of time without at the same time imparting to the polyethylene a phenolic odor perceptible to the average person The threshold concentration of trialkxyl substituted phenol in polyethylene at which a phenolic odor in polyethylene may be observed is about 0 2 per cent to 0 5 per cent depending of course on the particular phenol used Where a phenolic odor is unobjectionable or preferable over the rancid type odor developed in unstabilized polyethylene, amounts up to about 2 per cent to 4 per cent may be used without marked impairment of the normal physical properties of polyethylene such as tensile strength and solvent resistance. Incorporation and satisfactory dispersion of the phenol into the polyethylene can be by way of fluxing the polyethylene with the phenol on heating on heated open rolls, at which time fillers and/or coloring agents such as pigments or dyes may be added if desired. Other suitable mixing procedures include the use of Banbury mixers and of heated extruders of the single or double screw type. The use of a trialkyl substituted phenol to suppress odor is effective not only with clear polyethylene compositions, but also with

compositions pigmented with organic or inorganic compounds of chromium or manganese which when uninhibited often develop an odor more quickly than a clear polyethylene composition. Chromium and manganese compounds as for example hydrated chromic oxide, manganese dioxide, manganese ammonium pyrophosphate (Nurnberg Violet), employed as pigments in polyethylene compositions have been observed to accelerate odor development whereas other pigments, as for example titanium dioxide, are comparatively inert either in inhibiting or promoting odor development in polyethylene. The process and resultant products of the invention are further exemplified in the following examples: EXAMPLE 1 A six-pound batch of polyethylene having 75 an average molecular weight of 21,000 was compounded with 0 5 per cent by weight of 2,6-ditertiary butyl-4-methyl phenol in a Banbury mixer for 15 minutes at 135 C 1405 C to form a relatively concentrated 80 master batch dispersion of the phenol suitable for mixing with additional uninhibited polyethylene The hot master batch was transferred from the Banbury to mixing rolls having a roll surface temperature of 50 ' C to sheet 85 the batch The resultant sheets were cooled and then granulated One pound of this granulated composition was dry blended with 24 pounds of granulated uninhibited polyethylene (average molecular weight 21,000) by tumbling 90 for 30 minutes, producing a mixture containing 0.02 per cent by weight of the trialkyl phenol. The tumbled mix was fluxed at 150 ' C in an extruder, and the extruded product was pelletized One sample of these pellets was placed 95 in a clean glass jar which was then sealed to retain therein any odors which might be given off by the sample during storage at room temperature Another sample of the same pellets was extruded once more to determine the 100 effect an odor from this additional exposure to heat and this twice extruded product was also placed in a clean glass jar After storage for two weeks at room temperature, the jars containing the two phenol inhibited samples 105 together with a jar containing virgin polyethylene which had been subjected to the thermal abuse of only one extrusion operation were opened and compared as to odor content Both phenol inhibited polyethylene 110 samples were so essentially free of odor as determined by a staff of five experienced testers that the product could be used as molded containers or wrapping for such odor sensitive materials as foods, condiments, and 115 cosmetics The -jar containing virgin polyethylene sample when opened had a sharp xancid odor and was judged unsatisfactory for the aforementioned uses. EXAMPLE 2 An odor stabilized polyethylene composition pigmented with an organic

manganese compound and suitable for injection molding was prepared by fluxing in a Banbury mixer at C the following components: Parts by weight Polyethylene 100 0 Pigment Rubine 3 G" 1 0 2,4,6-tritertiary butyl phenol 0 2 786,000 a very strong, rancid and acidic odor developed after two months' storage at 40 C in sealed glass jars containing the granulated polyethylene.

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* GB786001 (A)

Description: GB786001 (A) ? 1957-11-06

Improvements in fuel supply systems for thermal power plants

Description of GB786001 (A)

P At TENT SPECFICATION __A 786,001 Date of Application and filing Complete Specification: Oct 21, 1955 No 30185155. Application made in United States of America on Oct 25, 1954. Complete Specification Published: Nov 6, 1957. Index at Acceptance:-Classes 110 ( 3), G 10 (A: B): and 135, P( 1 C l E:1 F: 8: 24 E 5: 24 KX). International Classification:-FO 2 c. COMPLETE SPECIFICATION. Improvements in Fuel Supply Systems for Thermal Power Plants. We, GENERAL ELECTRIC COMPANY, a Corporation of the State of New York, United States of America, Schenectady 5, State of New York, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following

statement:- This invention relates to fuel systems for thermal power plants and more particularly to dual fuel supply system for gas turbine power plant. The gas turbine normally runs on one fuel during any given period However, when the gas turbine is operated on gas received from a supplier there is to be considered the possibility that the available gas supply may not be sufficient for the turbine's needs. To meet this contingency the gas turbine is set up to receive a liquid-fuel to supplement a possible inadequate gas supply The gas and liquid fuel lines are fed into a dual fuel nozzle and then to the combustion chamber where the fuels are mixed in the desired proportions. The present invention has for its object to provide an improved dual fluid supply system for a thermal power plant having a combustion chamber. According to the present invention a dual fluid supply system for a thermal power plant comprises separate fuel supply lines for supplying two different fuels to the combustion chamber, separate controls for the respective fuels in the respective fuel lines, said controls being of the type which control fuel flow in response to an imposed pressure, means to produce a pressure signal responsive to the operating conditions of the power plant and a pressure divider by which the pressure signal is divided to operate the said lPrice 3 s 61 1 separate pressure controls, said divider comprising a housing with a central bore, a pressure fluid inlet port communicating with an intermediate portion of the bore and to which the aforesaid signal is transmitted, and first and second drain ports axially spaced on either side of the inlet port, a flow control member comprising an axially slidable stem member with three axially spaced lands disposed in said bore in cooperative relation with the inlet and drain ports, the said lands including a central land having an axial length less than the axial extent of the inlet port, a first drain land spaced axially from the central land and defining therewith in the bore a first fluid outlet chamber having a first pressure outlet port, the said first drain land also cooperating with its drain port to define a first drain orifice communicating with the first outlet chamber, when the flow control member is in neutral position, and a second drain land spaced axially from the said central land, the second drain land co-operating with the central land to define in the bore a second-fluid pressure outlet chamber having a second fluid pressure outlet port, the second drain land also co-operating with its drain port to define a second drain orifice equal in effective area to said first drain orifice when the flow control member is in its neutral

position, the two outlet ports being connected respectively to the aforesaid controls and means for positioning said flow control member axially so that the pressure signal can be so divided that the two fuels are supplied in the desired proportions. The invention will be better understood from the following description taken in connection with the accompanying drawings, in which: Fig 1 is a schematic view of the dual fuel system; 9 7 g 6,co 1 Fig 2 is a modified form of the dual fuel system; and Fig 3 is a sectional view of the pressure divider. Referring now more particularly to Fig. 1, the dual fuel system is shown applied to a gas turbine I containing a combustion chamber 2 to which fuel is supplied through a nozzle arrangement 3 The nozzle 3 is connected up to receive either gas or a liquid fuel, or both through conduits 4, 5 The flows of the fuels through the conduits 4, 5 are regulated by a gas control valve 6 and a fuel oil pump 7 respectively The fuel oil pump is controlled by pressure responsive means and the gas control valve is pressure responsive so that the pump and valve regulate the flow of fuel in accordance with an imposed control pressure The sum total of the fuel flowing through the fuel pump and gas control valve is regulated by a servo mechanism having speed, temperature and pressure responsive components A servo mechanism of this type is indicated diagram2, matically at 8 in the drawing and is arranged to regulate the hydraulic pressure in conduit 9 The regulator is supplied with oil pressure from a source through the conduit 9 a The regulator 8 produces an outlet pressure in conduit 9 which is determined by the operating condition of the turbine This signal pressure in conduit 9 determines the amount of fuel required to operate the gas turbine at the operating condition thereof. The pressure in conduit 9 will be referred to as the VCO (Variable Control Oil) pressure The VCO pressure is thus the pressure which determines the amount of fuel flowing into the gas turbine The VCO pressure enters the pressure divider assembly where it is split into two pressures P P 2. The sum of pressures P 1, P 2 is equal to the VCO pressure plus a desired constant which is determined by a back pressure arrangement to be discussed later in detail The two pressures P 1, P 2 are then transmitted to the gas control valve and fuel pump control respectively where they control the flow of gas and liquid fuel to the turbine. The gas control valve and fuel pump control are so designed that in response to an equivalent VCO pressure the total load available is substantially constant for a given VCO pressure regardless of the ratio of the pressures imposed on the gas control valve and fuel pump

control The pressure divider assembly 10, for example, may be set so that the entire signal pressure is transmitted to the gas control valve in which case the gas turbine will be run entirely on gas. On the other hand, the VCO pressure may be divided up so that both gas and liquid fuel will be supplied to the nozzle 3 In the latter case, the sum of the fuels flows to the combustion chamber will produce the required output load of the turbine. The pressure divider assembly may be manually regulated by the handle 11 to change the ratio of the signal pressure flowing to the fuel pump control and gas control 70 valve This manual change can be made at any time during the operation of the turbine without requiring the turbine to be shut down. In the modification shown in Fig 2, the 75 pressure divider assembly, is regulated by an electric motor 69 acting through a gear 72. Located in tie line between the electric source and the motor 69 is a pressure responsive switch 70 The switch is respon Si sive to the pressure in conduit 4 a which is transmitted through conduit 71 The switch is set so that if the pressure in conduit 4 a drops below a predetermined amount the motor circuit will be closed to energize the 85 motor and actuate the pressure divider assembly to divert more of the signal pressure to the fuel pump control so as to provide more liquid fuel to compensate for the reduced amount of gas available 90 Any suitable means is provided to stop the motor when the required adjustment has been made and to reverse the motor when the pressure in conduit 4 a rises above the predetermined pressure 93 With this arrangement the gas turbine can be set to operate on only gas within the range of its availability and to automatically cut in the second fuel only if the gas pressure should drop below a predetermined 100 value. This is done by first setting the pressure divider so that the entire signal pressure will be sent to the gas control valve If the requirements of the turbine are such as to 105 require more gas than is available the reduced gas pressure will be reflected in conduit 71 The pressure switch will then be closed to actuate the motor to divert some of the signal pressure to the fuel pump con 110 trol to reduce the amount taken from the gas line When the gas pressure is again normal the switch 70 will open to shut off the motor. The minimum pressure to be maintained in the line 4 a is usually set by the gas sup 115 plier This is done so that the turbine will not deprive other users of the gas by consuming too much of the available amount. Referring to Fig 3, there is illustrated in section, the VCO pressure divider 10 The 120 pressure divider comprises a piston valve assembly for dividing up the VCO pressure, a manually operated arrangement for

regulating the division of the VCO pressure, and a "constant adder" arrangement in the drain 125 line of the piston valve so that the pressure available for operating the fuel pump control and gas control valve never falls below a predetermined minimum provided the necessary control pressure in line 9 a is available 130 7 a 6,001 The piston valve assembly is located in a bore 16 defined by the housing 17 The valve assembly consists of a piston valve 18 slidably disposed in a valve sleeve 19 The S valve assembly is guided in the bore 16 by a tubular member 20. The valve sleeve 19 and tubular member define aligned axially spaced ports 21, 22, 23, 24 and 25 Ports 21 and 25 are drain ports and are in communication with passageway 26 defined by the housing for returning the drained oil to the reservoir 15 through conduit 14 (see Fig 1) The VCO, pressure is supplied to the valve assembly through conduit 9 and port 23 Ports 22, 24 are in communication with conduits 12 and 13 respectively for supplying the portion of the VCO pressure allotted to it to the fuel pump control and gas control valve 2 ' respectively. The piston valve 18 has axially spaced lands 28, 29, and 30 which regulate the flaw through inlet port 23 and drain ports 21 and respectively Uuper and lower chambers 2.5 33, 34 are formed between the land 28 and lands 30 and 29 respectively The land 28 is slightly smaller than port 23 and when centrally located relative to port 23 equal orifice openings 31, 32 are defined leading from inlet port 23 to outlet valve chambers 33 and 34 respectively With the land 28 in the central or neutral position, the lands 29 and 30 are so located as to form orifice openings 35, 36 between the valve chambers 33, 34 and the drain ports 25, 21 respectively These orifices 35, 36 are exactly equal to-orifices 31, 32. A back pressure is set up in the drain ports 21, 25 and drain line 26 by a relief valve 65 or other suitable constant adder means which can be set at any desired pressure. By way of example only, consider a VCO pressure in port 23 of 200 p s i and the back pressure in the drain ports 21, 25 and drain line 26 as being 40 p s i When the VCO pressure flows into the pressure divider assembly 10 the drain line 26 fills up developing a 40 p s i back pressure The difference between the VCO pressure and the back pressure in drain line 26 is the maximum drop that can occur across any flow path between the inlet and drain line 26 in the pressure divider assembly This relief valve arrangement prevents the pressure in valve chambers 33, 34 and conduits 12, 13 from falling below 40 p s i provided the necessary pressure in line 9 a is available. The minimum pressure in chambers 33, 34 provides for better operating characteristics of the fuel pump control and gas control valve, since they are spring loaded and are designed to operate accurately on a

minimum pressure of 40 p s i to avoid losses due to hysteresis. :rom the above it can be seen that there are two flow paths formed between the inlet port 23 and the drain line 26 The upper flow path is formed by port 23, orifice 31, valve chamber 33, orifice 35, port 25 and 70 drain line 26 The lower flow path is formed by port 23, orifice 32, valve chamber 34, orifice 36, port 21 and drain line 26 The total pressure drop in each of these flow paths will be 203 p s i (the assumed VCQ 75 pressure) minios the 40 p s i back pressure set up by the relief valve 65 There is no pressure drop through ports 22, 24 since they are part of a closed system leading only to the fuel pump control and gas control 80 valve for determining the amount of fuel flowing therethrough. It can be appreciated by one skilled in the art of fluid mechanics that with the land 28 in the neutral position relative to port 23 85 the drop across the equal orifice openings 31, 35 are identical Therefore, the total drop across orifices 31, 35 is equal to 200 p.s i (assumed VCO pressure) minus 40 p.s i (the back pressure set up by relief 90 valve 65) or 160 p s i The drop across each of tile orifices 31, 35 is one-half the total drop or 80 p s i Since the drop across orifice 31 is 80 p s i the pressure in chamber 33 and the pressure in conduit 13 for con 95 trolling the gas control valve is the VCO pfrssure ( 200 p s i) minus the pressure drop across orifice 31 ( 80 p s i) or 120 p s i. Now in considering the lower flow path through orifice 32, valve chamber 34, etc, 100 and the land 28 in the neutral position, the same flow principles can be applied The total drop across the lower flow path and the drop across each of the orifice openings 32, 36 is equal to the drop across the upper 105 flow path and the drop across each of orifices 31, 35 respectively The pressure in chamber 34 and in conduit 12 for controlling the fuel pump is therefore also 120 p s i. The sum of the pressures in conduits 12, 110 13 is 240 p s i or in other words is equal to the VCO pressure ( 200 p s i) plus the back pressure ( 40 p s i) fixed by the relief valve 65. If it is desired to run the turbine on, for 115 example, only oil, the piston valve is moved upward to close off orifice opening 31. When orifice 31 is closed off, orifice 36 is also blocked off due to the aforesaid relationship between the piston valve 18 and 120 the ports in sleeve 19 Therefore, the pressure in conduit 12 is equal to the VCO pressure At the same time it can be appreciated that since there is no pressure being supplied to valve chamber 33 and it is open 125 to drain line 25, the pressure in conduit 13 will become 40 p s i as determined by the relief valve 65 The total is still 240 p s i, or the VCO pressure plus the back pressure determined by relief valve 65 In this ex 1 ( O 7 $G,00 Q 1 treme position, it can be seen that the

turbine will be operated only on oil In the other extreme position, it will be operated on the other fuel. Now let us consider the piston valve in a position between the neutral and extreme positions In the neutral positions, orifices 31, 32, 35, 36 are all equal The lands 29, are so located that upon movement of the piston valve 18 in a downward direction the orifice 36 is opened by the amount orifice is closed At the same time the orifice 31 becomes larger by the amount 32 shrinks. Thus, when the piston valve is moved downwardly the total pressure drop across each of the flow paths remains the same but the drops across each of the orifices are changed. In the new position orifices 31 and 36 are equal and orifices 32 and 35 are equal. When the piston valve 18 is moved in a downward direction, the orifices 31, 36 are enlarged by the amount orifices 32, 35 are reduced The drop across the pairs of equal orifices are then correspondingly changed. That is, the drops across the smaller orifices are increased by the amount the drops across the larger orifices are decreased The pressure drops across orifices 31 and 36 are equal and the pressure drops across 32 and 35 are equal. The pressure in chamber 33 equals the VCO pressure minus the pressure drop across orifice 31 and the pressure in chamber 34 equals the VCO pressure minus the pressure drop across orifice 32 Therefore, assuming the pressure drop across orifice 31 to be 50 p s i the pressure in chamber 33 is 200 p s i (assumed VCO pressure) minus 50 p s i or 150 p s i The drop across the upper flow path is 200 p s i (VCO pressure) minus 40 p s i (relief valve back pressure) or 160 p s i The drop across orifice 35 therefore equals the pressure in chamber 33 ( 150 p s i) minus the back pressure ( 40 p s i) or 110 p s i. Since the pressure drop across orifices 32 and 35 is equal, the pressure in chamber 34 is 200 p s i minus 110 p s i (drop across orifices 35) or 90 p s i The sum of the pressure in chambers 33, 34 equals 150 + 90 p.s i and again equals the sum of the VCO pressure ( 200 p s i) plus the back pressure ( 40 p s i) determined by relief valve 65. Thus it can be seen that whatever position the piston valve is in, the sum of the pressures in conduits 12, 13 is equal to the VCO pressure plus a constant predetermined back pressure. The piston valve 18 is adapted to be moved downward to various positions by a manually operated handwheel 37 and is urged upwardly by a spring means 38. The arrangement for manuallv operating the piston valve includes a shaft 39 The shaft 39 extends through a chamber 66 defined by the

upper portion of the housing 17 and its ends are journaled in cap members 42, 43 The cap members are located in openings 40 41 defined by the housing and they are secured to the housing by bolts 44 T) The chamber 66 is closed off by a cover 67 which is secured to the casing by bolts 68. The shaft is rotated by a handle 11 secured to one end thereof Located on the shaft 39 is a cam member 45 which is adapted to 5 be in contact with a rod 46 Rod 46 extends through hole 47 defined by the cover member 48 which closes the chamber containing the valve assembly from the upper housing chamber 66 At its lower end the 50 rod contacts a bracket 49 secured to the piston valve 18 Thus it can be seen that upon rotation of the shaft 39 the cam 45 through the rod 46 and bracket 49 is capable of moving the piston valve 18 in a down 8. ward direction. Fastened to the lower end of piston valve 18 is a spring abutment member 50 The compression spring 38 is located between the spring abutment member 50 and a spring 91guide member 52 in the bottom of bore 16. The spring 38 urges the piston valve in an upward direction so that bracket 49 is maintained in contact with rod 46 and the rod in contact with cam 45 95 It can be appreciated that the location of the piston valve is positively determined by the operation of the handle 11 since the spring means 38 makes the bearing connection between the cam 45 and rod 46 the 1 (O( equivalent of a rigid connection. The relief valve 65 located in drain line 26 serves to set up a back pressure in the drain line This back pressure limits the pressure drop between the inlet port 23 and 105 the drain line 26 The setting of the relief valve determines the minimum pressure in the valve chambers 33, 34 provided there is the necessary control pressure in line 9 a. The relief valve is disposed in a bore 60 11 O in housing 17 and comprises a seat member 53 having an inlet opening 54 The seat member is retained in the housing 17 by a plate member 55 and bolts 56 A valve disk 57 is biased by a spring 58 to close lie inlet 54 The spring 58 abuts at its other end against an abutment member 59 which may be adjusted to give whatever spring force desired The member 59 is disposed in a cover plate 61 which is secured to hous _ 120 ing 17 by bolts 62 The end of the abutment member 59 is secured against tampering by a cap member 63 which is secured to the cover plate 61 by bolts 64. Thus it will be seen that the invention 125 provides for a dual fuel system which can be automatically regulated to provide a desired proportion of each of the fuels without requiring shutdown of the turbine The total amount of fuel required by the turbine 130 786,001 mitted, and first and second drain ports axially spaced on either side

of the inlet Po't, a flow control member compriginlg an axially slidable stern member with three 6,5 axially spaced lands disposed in said bore in co-operative relation with the inlet and drain ports, the said lands including a central land having an axial length less than the axial extent of the inlet port, a first 70 drain land spaced axially from the central land and defining therewith in the bore a first fluid outlet chamber having a first pressure outlet port, the said first drain land also co-operating with its drain port to 75 define a first drain orifice communicating with the first outlet chamber, when the flow control member is in neutral position, and a second drain land spaced axially from the said central drain land, the second drain 80 land co-operating with the central land to define in the bore a second-fluid pressure outlet chamber having a second-fluid pressure outlet port, the second drain land also co-operating with its drain port to define 85 a second drain orifice equal in effective area to said first drain orifice when the flow control member is in its neutral position, the two outlet ports being connected respectively to the aforesaid controls and means for posi 90 tioning said flow control member axially so that the pressure signal can be so divided that the two fuels are supplied in the desired proportions. 2 A dual fuel supply system as claimed 95

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* GB786002 (A)

Description: GB786002 (A) ? 1957-11-06

Improvements in jacks

Description of GB786002 (A)

I, Au GUSTF F Av RE, of 406 Rue Paradis,

Marseille, France, of French nationality, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to jacks, its object being to provide an improved construction primarily for use in docks for ship building and repair. According to the present invention, a shiftable jack for use in shipyards, comprises a rail track for positioning in the path along which the jack is to be shifted, a rigid frame positioned over said track, roller means journalled in the frame and positioned on said track for supporting the frame thereon, a cylinder of a hydraulically operable piston and cylinder lifting device mounted on the frame with its axis normal to the track, a piston slidable in said cylinder and extending from an end thereof for seating against a load to be supported, a cylinder of a hydraulically operable piston and cylinder shifting device coupled to the track, and a piston slidable in said shifting cylinder and coupled to the frame, whereby the frame is movable to a selected position along the track by application of fluid under pressure to the shifting device. Preferably the journals for the roller means are resiliently coupled to the frame such that the rollers support part of the weight of the frame. The jack may include a chamber in the lower part for hydraulic liquid, a non-return inlet valve in the base of the lifting cylinder, a conduit opening at one end to said inlet valve and at the other end in the liquid chamber of the frame, means for supplying compressed fluid to the chamber to force liquid therefrom into the lifting cylinder and lPrice 3 s 6 d l lift the piston therein, and an outlet valve on the lifting cylinder for releasing liquid from said cylinder when the piston is to be lowered This enables the lifting device to be brought rapidly up to the load, whereafter rigid support is given by the liquid which has entered through the non-return valve. A resilient sole plate may be provided on the piston of the lifting device for more readily contacting the load in an even manner. An embodiment of the invention is hereinafter particularly described with reference to the accompanying drawing, wherein:Figure 1 shows in longitudinal vertical section, a jack for use in dry docks. Fig 2 shows means for lateral movement of the jack. The apparatus consists of a frame 1 comprising at its lower part 2, which forms the base, a reservoir 3 containing a liquid 4. The air space 5 of this reservoir has an inlet orifice 6 for the entry of air under pressure.

A vertical conduit 7 depends below the surface of the liquid and has its upper end opening into the base of a cylinder 8 At the bottom end of the cylinder is an opening closable by a non-return valve 9 which permits introduction of the liquid beneath the lower face 10 of a piston 11 slidable in the cylinder and carrying a head or top plate 12. A pipe 13 with cock 14 is disposed at the lower part of the cylinder 8 and allows of its being put into communication through the branch pipe 15 with the reservoir 3. The base 2 comprises a traction arm 16 joined by a pivot 17 to a piston rod 18 which has a travel of several metres The cylinder 19 and the rod 18 (see Fig 2) are lodged in a trough so as not to obstruct the runway 24. Centrally at its base the jack is provided 7865002 PATENT SPECIFICATION Date of Application and filing Complete Specification: Dec 13, 1955 No 35727/55. Application made in France on Dec 20, 1954. Application made in France on Nov 29, 1955. Complete Speci cation Published: Nov 6, 1957. Index at Acceptance -Class 78 ( 3), C( 1: 7 8:13: 15). International Caasifieation:-B 66 f. COMPLETE SPECIFICATION. Improvements in Jacks. 65, 786,002 with rolling members 20 mounted on resilient bearings consisting of a cushion 21 and a sole plate 22, the whole being assembled together by straps and fitted in a housing 23 in such a manner as to be able to roll along the runways 24 A resilient sole plate 25 is secured to the movable platform 12. It is well-known that hydraulic mechanisms in general are relatively efficient for the transmission of high power at low speeds. Nevertheless, the power absorbed unladen whilst bringing a hydraulic jack up to contact with the load is nearly as great as that required to effect lifting, so that the overall efficiency is thereby greatly reduced and such jacks become costly to operate when considerable distances have to be covered. By utilising a combination of pneumatic and hydraulic operation, these drawbacks are eliminated. When the apparatus is used as a hydraulic jack for putting vessels into dry dock, the jacks are disposed suitably along the keel and when the vessel tends to heel over during emptying of the dock, the operator, who is on land, opens a valve which allows compressed air to pass to the reservoir 3 through the orifice 6 This air under pressure drives out the water through the conduit 7 into cylinder 8 past the

valve 9, whereby the piston I rises in the cylinder and forces the head 12 with its sole plate '25 against the ship to support it. When the piston ceases to rise, the valve 9 closes and the return of the liquid is prevented (the cock 14 also being closed). The piston 11 then is supported solely by liquid and not by air, and thereby gives a firm pressure capable of supporting very high loads, e g as much as 300 tons. In the special case where it is desirable that the vessel should not be supported at strong pressure but should rest on a resilient support, the cock 14 is left open and the jack exerts resilient air pressure. Where it is desired thereafter, with the vessel in dry dock, to the vessel, it is only necessary to connect the cylinder S with a portable pump. Where the jack has been set beneath an inclined part of the vessel, there can be placed beforehand on the top plate of the piston a resilient or inclinable wedge, or the jack may be constructed with two pistons o 5 instead of one, each piston acting on an extremity of the top plate which, under pressure, will assume the inclination of the side of the vessel. It is possible to move the jack and place it in a desired position during or before the entry of the vessel into dry dock This operation is effected by remote control from land The shifting jack 19 may be pneumatic or hydraulic and of either single or double action 65 The jack can be pushed or pulled to the required position, e g the desired lateral separation from the keel support in a dry dock. The resilient bearings 21, 22 for the wheels 70 are adjustable by tightening screws (not showe) in such a manner as to permit carrying from 213 to 314 of the submerged weight of the jack The jack remains permanently on its runway, and the bearing 75 of a major portion of its weight by the wheel 20 facilitates rolling and sliding on the paths 24.

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* GB786003 (A)

Description: GB786003 (A) ? 1957-11-06

Novel dehydro-betacarotene and the manufacture and conversion thereof

Description of GB786003 (A) Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

COMPLETE SPECIFICATION Novel Dehydro-BetaCarotene and the Manufacture and Conversion thereof We, F. HOFFMANN-LA ROCHE & Co., AKTIENGESELLSCHAFT, a Swiss Company, of 124-184, Grenzacherstrasse, Basle, Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to novel dehydro-betacarotenes and a process for the manufacture thereof and to the conversion thereof into all-trans 3,4;31,41-bisdehydro- betacarotene. The novel dehydro-betacarotenes provided by the invention are 3,4;31,41;15,151-trisdehydro-betacarotene and 15,151-monocis 3,4; 31,41 - bisdehydro - betacarotene. They can readily be converted into all-trans 3,4;31,41 bisdehydro-bctacarotene which is useful as a colouring material for foodstuffs (e.g. butter, margarine and cheese) and for animal feeds. As it possesses biological activity characteristic of vitamin-A it imparts this activity as well a its orange-red colour to the nutrient materials in which it is incorporated. The process provided by the invention essentially comprises condensing acetylene with 8-[21,61,61-trimethyl-cyclohexadien-(11, 31) - yl - (11(1 - 2,6 - dimethyl - octatrien- (2,4,6)-al-(1) or 8-[21,61,61-trimethyl-cyclo- hexen - (21) - ylidene - (11)] - 2,6 - dimethyl- octatrien-(2,4,6)-al(1) in a metal-organic reaction,

subjecting the resulting 1,18-di-[21,61,61trimethyl-cyclohexadien-(11,31)-yl-(11)]-3,7,12, 16 - tetramethyl - 8,11 - dihydroxy - octadecahexaen-(294,6912,14,16)-ine-(9) or 1,18-di-[21, 61,61-trimethyl-cyclohexen-(21)-ylidene-(11)]-3, 7,12,16 - tetramethyl - 8.11- dihydroxy - ecta- decahexaen-(2,4,6,12,14,16)-ine-(9) to bilateral allyl rearrangement and dehydration and if desired, partially hydrogenating the 3,4;31,41; 15,151-trisdehydro-betacarotene at the triple bond to obtain 15,151-monocis 3,4;31,41-bis- dehydro-betacarotene. The last named sub stance can be converted in accordance with the invention into all-trans 3,4;31;41-bisdehdyro-betacarotene by isomerisation. One embodiment of the invention which includes the conversion step comprises condensing acetylene with approximately two molar proportions of 8-[21,61,61-trimethyl- cyclohexadien - (11,31) - yl - (11)] - 2,6 - dimethyl-octatrien-(2,4,6)-al-(1) or 8-[21,61,61trimethyl - cyclohexen - (21) - ylidene - (11)]2,6-dimethyl-octatrien-(2,4,6)-al-(1) to give 1, 18-di [21,61,61-trimethyl-cyclohexadien-(11,31)yl - (11]) - 3,7,12,16 - tetramethyl - 8,11dihydroxy - octadecahexaen - (2,4,6,12,14,16)- ine-(9) or 1,18-di [21,61,61-trimethyl-cyclohexen-(21)-ylidene-(11)]-3,7,12,16-tetramethy l8,11 - dihydroxy - octadecahexaen - (2,4,6,12, 14,16)-ine-(9) respectively [either in a single operation, wherein one mol of aldehyde is condensed with each of the reactive hydrogen atoms in acetylene by means of a bilateral metal-organic reaction or, stepwise, wherein one mole of the aldehyde is condensed with one mol of acetylene by a metal-organic reaction thereby producing the intermediate condensation product 10 - [2l,6l,6l - trimethyl - cyclohexadien - (113l) - yl - (11)] - 4,8 - dimethyldecatrien-(4,6,8)-irl-(1) < 1-(3) or 10-[21,6l,6l- trimethyl-cyclohexen-(21)-ylidene-(11)]-4,8-dimethyl-decatrien-(4,6,8) -in-(1)-ol-(3) respectively and condensing this product with a second mol of the aldehyde by means of a metal-organic reaction], subjecting said dihydroxy compound to dehydration with concomitant allyl rearrangement to give 3,4;31, 41;15,151-trisdehydro-betacarotene, if desired hydrogenating the last named substance with about one molar proportion of hydrogen in the presence of a hydrogenation catalyst which selectively catalyzes the hydrogenation of an acetylenic linkage to an olefinic linkage to give 15,1 51-monocis 3,4;31,4l-bisdehydro-betacaro- tene and, if further desired, isomerizing the latter to give all-trans 3,4;31,41-bisdehydrobetacarotene. In the first stage wherein acetylene is condensed bilaterally with

either aldehyde in a metal-oraganic reaction, an appropriate embodiment comprises condensing acetylene di-(magnesium halide) trith about two molar proportions of either aldehyde in a Grignard reaction. The acetylene di-(magnesium halide) can be prepared in a Imown manner by the action of acetylene on a solution of lower-alkyl magnesium halide in an inert solvent; preferably, an ethereal solution of lower-alkyl magnesium halide is stirred or shaken in an acetylene atmosphere for several hours. Suitable lower-alkyl magnesium halides are, for example, ethyl, butyl and r-hexyl magnesium bromides and chlorides. In this reaction the acetylene di-(magnesium halide) produced separates as a heavy oil or as a solid. It is then appropriate to add about two molar proportions of either aldehyde dissolved in an inert solvent (preferably diethyl ether) to the well stirred suspension of the acetylene di-(magnesium halide) and to Stir the mixture for several hours at ci 200 G or at the boiling point of the solvent. Upon hydrolysis of the reaction product there is obtained the corresponding dihydroxy compound aforesaid as a very viscous material. In the first stage wherein acetylene is stepwise condensed, an appropriate embodiment comprises condensing approximately one molar proportion of either aldehyde in liquid ammonia with one molar proportion of an alkali-metal or an alkaline-earth-metal acetylide and reacting the product obtained (advantageously after hydrolysis) in a metal-organic reaction with a second approximately molar proportion of the aldehyde. The condensation in liquid amroonaa can be executed either at elevated pressures and room temperature (i.e. ca 200 C.) or under normal pressures and at the boiling temperature of the ammonia. Preferably, lithium acetylide is employed in the condensation. The aldehyde can be added in solution in an inert solvent, for example, diethyl ether. The condensation product can best be hydrolysed by addition of an ammonium salt before removal of the ammonia or by addition of an acid after removal of the ammonium. Condensation of the resulting 10-[21,61,61-trimethyl-cyclohexadien(1i,3l) - yl - (I)] - 4,8 - dimethyl - decatrien(4,6,8)-in-(1)-ol-(3) or 10-[21,61,61-trimethylcyclohexen - (21) - ylidene - (11)] - 4,8 - di- methyl-decatrien-(4,6,8)-in-(1)-ol-(3) as the case may be with a second approximately molar proportion of the aldehyde is effected by means of a meta] erganic reaction. The preferred mode of execution comprises reacting either monohydroxy compound with approximately two molar proportions of a lower-alkyl magnesium halide in diethyl ether. The first molar proportion of the lower-alkyl magnesium halide reacts with the hydroxyl group whereas the second molar proportion reacts with the acetylene hydrogen and renders the terminal carbon atom of the compound reactive in the subsequent step of the condensation. The

di-(magnesium halide) compound formed is advantageously reacted in the same solvent with the aldehyde. The condensation product is preferably hydrolysed by conventional methods without further purification (for example, by pouring into a mixture of ice and dilute sulphuric acid) thereby producing the required dihydroxy compound. In the second stage each hydroxyl group of the dihydroxy compound obtained after the first stage, after esterification if desired, migrates by a multiple allyl shift toward the nearer ring, and splits out two molar proportions of water (or acid when the compound has been esterified) by combining with a hydrogen atom and two new double bonds are formed and simultaneously all of the multiple bonds are rearranged into a conjugated system to give 3,4;31,41;15,151-trisde- hydro-betacarotene. It will be appreciated that the phrase "bilateral allyl rearrangement and dehydration " is used herein to denote the elimination of two moles of water from, and the formation of a conjugated system in, the product of the first step-irrespective of whether these changes are brought about directly or via intermediate ester formation. The bilateral allyl rearrangement and dehydration can be effected by various expedients. A general method comprises heating a solution of either of the dihydroxy compounds in an inert solvent such as toluene to a temperature of about 90 C. to about 100 C. with about two molar proportions of phosphorus oxychloride in the presence of an organic base such as pyridine. In stead of phosphorus exychlorde and pyridine there may be used p-toluene-sulphonic acid, hydrochloric acid, hydrobromic acid or acetic acid (the last mentioned in the presence of sodium acetate and a little water). A preferred method for the treatment of 1,18-di[21,61,61triscthyl - cyclohexadien - (11,31) - yl - (11)] - 3,7,12,1 6-tetramethyl-8, 11-dihydroxy-octa- decahexaen-(2,4,6, 12,l4,16)-ine-(9) comprises reacting the same with hydrogen halide at a low temperature (advantag@ously in the presence of a loser alkanol as solvent) whereupon a 1,18-di[21,61,61-trimethyl-cyclohexadien(11.3i) - yl - (1')] - 2,17 - dihalo - 3,7,12,16 tetraxnethyl - octadecahexaen (3,5,7,11,13,15)in-(9) is first formed and spontaneously splits out two mols of hydrogen halide with the formation of two additional double bonds. The trisdehydro compound formed in this stage can be purified by crystallisation. In the optional third stage, the partial hydrogenation can be accomplished according to methods kno-zm per se; e.g. by reaction with elemental hydrogen in the presence of a selective hydrogenation catalyst in an organic solvent. A suitable selective hydrogenation catalyst is a palladium/calcium-carbonate catalyst which has been partially deactivated with lead and quinoline. An especially

advantageous mode of execution of this third stage comprises effecting the hydrogenation in a hydrocarbon medium in which the 3,4;31,41;15,151-trisdehydro-betacarotene is only partially soluble. In this manner, the trisdehydro compound slowly goes into solution as the hydrogenation proceeds and the hydrogenation product is precipitated from the hydrogenation mixture as it is formed. The 15,151-monocis 3,4;31,41-bisdehydro-betacarotene so obtained has a characteristic cis-peak" in the ultraviolet absorption spectrum. Isolation of the hydrogenation product is not mandatory as the subsequent stage of isomerisation can be effected directly upon the suspension. However, if desired, the hydrogenation product can be isolated and purified by crystallisation. In the conversion step comprising the final stage of the comprehensive process, the 15,151monocis 3,4;31,41-bisdehydro-betacarotene is isomerised to the corresponding all-transcompound. This isomevisation can be effected, for example, by treatment with iodine or by irradiation or by heat. A particularly advantageous mode of execution comprises heating a suspension of 15,15'monocis 3,4;3l,4l-bisdehydro-betacarotene for several hours at 80 -100 C. in a quantity of an organic liquid vehicle insufficient for the complete solution of th monocis material. As the isomerisation progresses, the monocis compound goes into solution and simultaneously the all-trans 3,4;31,41-bisdehydro- betacarotene formed crystallizes out and an almost quantitative isomerisation can thereby be attained. The product obtained in this way can be purified by crystallization or by partition between solvents or by chromatography. It can be stabilised, when neces- sary, by the addition of antioxidants. Antioxidants can also be employed in the other stages of the process of the invention. As will be seen from the foregoing an important feature of the invention resides in the preparation of all-trans 3,4;31,4l-bisde- hydro-betacarotene by a process which comrises partially hydrogenating 3,4;31,41;15,151- trisdehydro-betacarotene at the triple bond to give 15,151-monocis 3,4;31,41-bisdehydrobetacarotene and isomerising same to give all - trans 3,4 3194J - bisdehydro - beta carotene. It will be understood that the numbering system employed herein for the carotene afere- said is that set forth in Leibig's Annalen der Chemie, 1951, 573, 3 for the carbon skeleton of carotene. The following example is illustrative of the process and conversion and includes the preparation of the inital materials: EXAMPLE PREPARATION OF THE INITIAL MATERIAL A) 8 - [21,61,61-TRIMETHYL-CYCLOHEXADIEN ( 3I) - YL - (11)] - 2,6 - DIMETHYL-OCTA TRIEN-(2,4,6)-AL-(1):

30 g. of 4-[21,61,61-trimethyl-cyclohexen (11)-yl-(11)]-2-methyl-buten-(2)-al-(1) in 210 g. of methylene chloride, together with 13.5 g. of sodium bicarbonate and 9 g. of calcium oxide, was cooled to 0 C. while stirring. Then 28 g. of N-bromo-succinimide was added and the temperature was maintained for 3 hours at 5 C. to 10 C. by intermittent cooling. After some time the mixture assumed a yellow to red colour and then slowly became colourless again. It was filtered, 30 g. of quinoline was added and the methylene chloride was removed in oacuo. Again 30 g. of quinoline was added and the mixture was warmed for 2 hours under nitrogen on a steam bath. 350 g. of petroleum ether (b.p.=300 C. to 60 C.) was added and then the mixture was poured into 250 g. of 3-N sulphuric acid and ice while stirring. The insoluble resin was filtered off and the aqueous layer was also removed; the residual petroleum-ether solution was washed with water, dilute sodium bicarbonate solution and then again with water. The washed petroleum ether solution was dried over sodium sulphate and concentrated, yielding 29.4 g. of crude 4-[21,61,61-trimethyl-cyclohexen-(21)ylidene-(11)]-2-methyl-buten-(2)- al-(1). This product was purified by distillation from a Hickman flask in a high vacuum; b.p. 90 C./ 0.33 mm. Hg. 136 g. of 4-[21,61,61-trimethyl-cyclohexen- (21) - ylidene - (11)] - 2 - methyl - buten (2)-al-(1) were heated with 97 ml. of isopropenyl acetate and 0.7 g. of p-toluene-sulphonic acid for 3 to 4 hours at 100 C. to 140 C. while passing through a slow stream of nitrogen, the acetone released being thus continuously distilled out of the reaction mixture. Then the reaction mixture was allowed to cool. The reaction mixture, containing crude 4 -[21,61,61 - trimethyl - cyclohexadien - (11, 31) - yl - (11)] - 2 - methyl - 1 - acetoxy butadiene-(1,3), was directly subjected to hydrolysis by adding thereto 650 ml. of metha- nol, 65 ml. of water and 46 g. of sodium bicarbonate and heating the mixture under reflux for 12 hours, while stirring. The reaction mixture was then poured into 2000 ml. of ice water, and the resulting mixture was made slightly acidic with dilute sulphuric acid. The reaction product was extracted with petro leum ether, the extract was washed with aqueous sodium bicarbonate solution and dried over sodium sulphate. The solvent was evaporated and the residue was distilled in a high vacuum. There were obtained 98 g. of 4 - [21,61,61 - trimethyl - cyclohexadien (11,31)-yl-(11)]-2-methyl-buten-(2)-al-(1) b.p.= 80 C./0.05 mm. Hg.; nD22=1.530; maxima in ultraviolet at 224 mji and 268 my; E11= 795 and 345 (in petroleum ether solution).

A solution of 82 g. of 4 - [21,61,61 - tri methyl - cyclohexadien - (11,31) - yl - (1')] 2-methyl-buten-(2)-al-(1) in 90 ml. of ethyl orthoformate was mixed with a solution of 1.5 ml. of orthophosphoric acid in 15 ml. of absolute ethanol, and the mixture was allowed to stand for 15 hours at 20 C. to 25 C. Then 10 ml. of pyridine was added and the mixture was poured into a mixture of 100 g. of 5 O aqueous sodium bicarbonate solution and 60 g. of ice. The reaction product was extracted with petroleum ether, the extract was shaken with aqueous sodium bicarbonate solution and dried over potassium carbonate. The solution was concentrated, and the residue was freed in vacvo at 70 C. from excess ethyl orthoformate and the ethyl formate produced by reaction. The residue, 108 g. of crude 4 - [21,61,61 - trimethyl - cyclohexadien (11,31) - yl - (11)] - 2 - methyl - 1,1 - di ethoxy-butene-(2), had nD25=1.487; absorption maximum in the ultraviolet spectrum at 266 mlt (in petroleum ether solution). It was used without further purification for the next step. To the above 108 g. of material was added 3 ml. of a 10% by weight solution of zinc chloride in ethyl acetate; then 29 g. of ethyl vinyl ether and 27 ml. of the same 10% solution of zinc chloride in ethyl acetate were added simultaneously, with stirring, at 30 to 35 C., over a period of about 2 hours. Stirring was continued 20 hours longer at ca 20 C. The crude 6-[21,61,61-trimethyl-cyclo- hexadien - (11,31) - yl - (11)] - 4 - methyl 1,1,3-triethoxy-hexene-(4) obtained in this manner was added to a mixture of 300 ml. of glacial acetic acid, 15 g. of sodium acetate and 10 ml. of water, and the reaction mixture was heated at 95 C. for 6 hours in a nitrogen atmosphere. The reaction mixture was cooled to 30 -40 C., poured into a mixture of 200 g. of ice and 200 ml. of water. The resulting mixture was extracted with petroleum ether, the extract was washed with 5% aqueous sodium bicarbonate solution and then with water and dried over sodium sulphate. The petroleum ether solution was concentrated and the residue was distilled 'n a high vacuum. There were thus obtained 65 g. of 6 - [21,61,61 - trimethyl - cyclohexadien-(11, 31) - yl - (11)] - 4 - methyl - hexadien - (2,4) al-(1); b.p.=about 105 5./0.05 nun. Hg. This material was recrystallized twice from petroleum ether at minus 70 C., yielding yellowish crystals of m.p. 18 C. to 22 C.; ultraviolet absorption maximum at 274 m , E11=1380 (in petroleum ether solution). A solution of 38.5 g. of 6 - [21,61,61 - tri methyl - cyclohexadien - (11,31) - yl - (11)] 4-methyl-hexadien-2,4)-al-(1) in 40 ml. of ethyl orthoformate was mixed with a solution of 0.6 ml. of orthophosphoric acid in 9 ml. of absolute ethanol, and the reaction mixture was allowed to stand for 15 hours at 20 C. to 25 C. Then 6 ml. of pyridine

was added, and the mixture was poured into a mixture of 50 g. of 5% aqueous sodium bicarbonate solution and 30 g. of ice. The product was extracted from the resulting mixture with petroleum ether, the petroleum ether extract was shaken with aqueous sodium bicarbonate solution and dried over potassium carbonate. The petroleum ether solution was concentrated and the residue was liberated in vacuo at 70 C. from excess ethyl orthoformate and from the ethyl formate produced by the reaction, yielding 49 g. of 6 - [21,61,61 - trimethyl cyclohexadiene - (11,31) - vl - (11)] - 4 methyl-1,1-diethoxy-hexadiene-(2,4), nD26= 1.510 ultraviolet absorption maxima at 235 my. and 264 my (in petroleum ether solution). This material was used for subsequent processing without further purification. The above 49 g. of material was mixed with 2 ml. of a 10% by weight solution of zinc chloride in ethyl acetate. Then, 14 g. of ethyl propenyl ether and 14 ml. of the same 10% solution of zinc chloride in ethyl acetate were added simultaneously, with stirring, at 20 C. to 35 C, over a period of 2 hours. The reaction mixture was stirred further for 15 hours at ci 20 C. Then the reaction mixture was extracted with petroleum ether, the extract was washed with dilute aqueous sodium hydroxide solution and dried over potassium carbonate. The solvent was distilled off, yielding 55 g. of crude 8 - [21,61,61 trimethyl - cyclohexadien- (11,31) - yl - (1l)] 2,6 - dimethyl - 1,1,3 - triethoxy - -octadiene - (4,6), nD22=1.501, ultraviolet absorption maxima at 236 m and 262 m (in petroleum ether solution). This material was processed without further purification. The, above 55 g. of material was mixed with 120 ml. of glacial acetic acid, 10 g. of sodium acetate and 6 ml. of water. A trace of hydroquinone was added, and the reaction mixture was heated at 95 C. for 6 hours. The mixture was then cooled to 30 C. to 40 C. and poured into a mixture of 100 g. of ice and 1C3 ml. of water. The reaction product was extracted with petroleum ether, the petroleum ether extract Tras washed with aqueous sodium bicarbonate solution and then with water, and dried over sodium sulphate. The petroleum ether solution was concentrated, and the residue was distilled in a high vacuum, yielding 30 g. of 8 - [21,61,61 - trimethyl - cyclo hexadien - (11,3l) - yl - (11] - 2,6 - dimethyl octatrien-2,4,6)-al-(1) [b.p.=138 to 143 C./0.08 mm. Hg.] which soon solidified into a crystalline mass. The material was recrystallised twice from twice its weight of petro leum ether at minus 70 C., yielding yellow crvstals of m.p. 64 C. to 66 C., ultraviolet absorption maximum at 315 m , E11=1745 (in petroleum ether

solution). B) 8-[21,61,61-TRIMETHYL-CYCLOHEXEN-(21) YLIDENE - (11)] - 2,6 - DIMETHYL - OCTA TRIEN-(2,4,6)-AL-(1): To a solution of 49.5 g. of 4 - [21,61,61 trimethyl cyclohexen - (21) - ylidene - (11)] - 2-methyl-buten-(2)-al-(1) in 54 g. of ethyl orthoformate was added a solution of 1 ml. of orthophosphoric acid in 9 ml. of absolute ethyl alcohol, and the mixture was set asid for 15 hours at 200 C. to 25 C. Thereupon 10 g. of pyridine was added and the mixture was poured into a mixture of 10G g. of 5 aqueous sodium bicarbonate solution and 6G g. of ice. The resulting mixture was extracted with petroleum ether and the extract was shaken with aqueous sodium bicarbonate solution and dried over potassium carbonate. Th petroleum ether solution was concentrated and the residue was fred in vacuo at 70 C. of excess ethyl orthoformate and of the ethyl tormate produced by reaction, thereby yielding 70 g. of 4-[21,6l,6l-trimethyl-cyclohexen- (21) - ylidene - (11)] - 2 - methyl - 1,1 - di ethoxy-butene)-(2); nD22=1.5155; absorption maximum in the ultraviolet spectrum at 284.5 m (in petroleum ether solution). The last na@ned compound, without further purification, was condensed with ethyl vinyl ether. To this end, 3 ml. of a 10% solution of zinc- chloride in ethyl acetate was added to the 70 g. of the compound, then 20 g. of ethyl vinyi ether and 18 ml. of a 10% solution of zinc chloride in ethyl acetate was added simultaneously, with stirring at 30 C. to 35 C., over a period of 2 hours. The stirring was continued 20 hours longer at ca 20 C. The crude 6-[21,61,61-trimethyl- cyclohexen - (21) - ylidene - (11] - 4 - methyl 1,1,3-triethoxy-hexene-(4) obtained in this manner was treated with a mixture of 240 ml. of glacial acetic acid, 12 g. of sodium acetate and 6 ml. of water and heated for 6 hours in a nitrogen atmosphere at 95 C. Then it was cooled to 30 C. to 40 C. and poured into a mixture of 200 parts by weight of ice and 200 parts by volume of water. The oily reaction product was extracted with petroleum ether, the extract was washed with 5% aqueous sodium bicarbonate solution and with water and dried over sodium sulphate. After concentration of the petroleum ether solution, the residue was distilled in a high vacuum. There were obtained 61 g. of 6-[21,61,61-trimethyl - cyclohexen - (21) - ylidene - (11)] 4-methyl-hexadien-(2,4)-al-(1) as a mixture of isomers, b.p. about 125 C.iO.02 mm. Hg. By crystallization from petroleum ether at minus 70 C., there was obtained a yellow crystalline form, m.p. 73 C.-740 C.; ultraviolet absorption maxima at 353 na and 372 m ; E11=2360 and 2200 (in petroleum ether solution). A residual oily isomer was converted in part into the crystalline isomer by heating with acetic acid and

sodium acetate at 95 C. for 5 hours; by repeated treatment of the mother liquor, practically the entire quantity was obtained in the form of the crystalline isomer. To a solution of 50 g. of crystalline 6 - [2l,6l,6l - trimethyl - cyclohexen - (21) ylidene - (11)] - 4 - methyl-hexadien - (2,4) al-(1) in 54 ml. of ethyl orthoformate was added a solution of 1 ml. of orthophosphoric acid in 9 ml. of absolute ethyl alcohol, and the mixture was set aside for @@ hours at 200 C. to 25 C. Then 10 ml. of pyridine was added and the mixture was poured into a mixture of 10 g. of 5 u,, aqueous sodium bicarbonate solution and 60 g. or ice. The resulting mixture was extracted with petroleum ether, the extract was shaken with aqueous sodium bicarbonate solution and dried over potassium carbonate. Then the petroleum ether solution was concentrated and the zesi- due was freed from excess ethyl orthoformate and trom the ethyl formate produced oy tire reaction an vacuo at 700</RTI STAGE 1 1A) 16 g. of magnesium and 110 g. of n-hexyl bromide were reacted in 330 ml. of absolute diethyl ether, thereby forming an ethereal solution of fg-hexyl magnesium bromide. This Grignard solution was stirred for 24 hours in an atmosphere of acetylene. Two layers were formed. The upper layer was separated eN. The lower layer was washed once with 100 ml. of absolute diethyl ether and to the washed material was added 200 ml. of absolute diethyl ether and then a solution of 80 g. of 8-[21,61,61-trimethyl-cyclo- hexadien - (1l,3l) - yl - (11)3 - 2,6 - dimethyloctatrien-(2,4,6)-al-(1) in 200 ml. of absolute diethyl ether was added quickly. The mixture was heated under reflux for 3 hours, while stirring in a nitrogen atmosphere. Then the reaction mixture was cooled, poured into a mixture of 75 g. of ammonium chloride and 175 g. of ice-water and the whole was stirred well for 10 minutes. The ether layer was separated, washed thrice (each time with 209 ml. of water) and the washed ethereal solution was dried over sodium sulphate. The ether was driven off, yielding 87 g. of y llow, resinous, 1,18 - di[21,61,61 - trimethyl - cyclo hexadien - (11,31) - yl - (11)] 3,7,12,16 tetramethyl - 8,11 - dihydroxy - octadeca hexaen-(2,4,6,12,14,16)-ine-(9), having an absorption maximum in the ultraviolet spectrum at 285 m (in petroleum ether). 2A) Dry acetene-free acetylene was introduced into a solution of 3 g. of lithium in 1200 mI. of liquid ammonia until there was no further reaction. Then while stirring vigorously, a solution of 100 g. of 8-[21,61,61- trimethyl - cyclohexadien - (11,31) - yl - (11)] 2,6-dimethyl-octatrien-(2,4,6)-al-(1) in 400 ml. of absolute diethyl ether was added over a period of 20 minutes and the reaction mixture

was stirred thoroughly for 20 hours while taking precaution to exclude moisture. Thereupon 50 g. of ammonium chloride was added in small portions and the ammonia was permitted to evaporate. 400 ml. of water was added and the ether layer was separated and washed with water and then dried over sodium sulphate and concentrated. The residual reddish oil was dried well in vacuo. There was obtained 108 g. of 10-[21,61,61-trimethyl cyclohexadien - (11,31) - yl - (11)] - 4,8 - di methyl-decatrien-(4,6,8)-in-(1)-ol-(3) as a viscous oil, having an absorption maximum in the ultraviolet spectrum at 284 m (in petroleum ether). Determination of active hydrogen according to Zerewitinoff's method showed, in the cold, one active hydrogen atom; and in the warm, two active hydrogen atoms. The last named compound (108 g.) was dissolved in 500 ml. cf absolute diethyl ether and was added gradually at 15 C.-200 C., while stirring to a Grignard solution prepared from 18 g. of magnesium 91 g. of ethyl bromid and 300 ml. of absolute diethyl ether. The reaction mixture was heated under reflux for one hour in a nitrogen atmospnere and then cooled with ice-water. A solution of 92 g. of 8 - [21,61,61 - trimethyl - cyclohexa dien - (11,31) - yl - (11)] - 2,6 - diemthyl octatrien-(2,4,6)-al-(1) in 400 ml. of absolute diethyl ether was added at about 20 C. and the reaction mixture was heated under reflux for 3 to 4 hours in a nitrogen atmosphere. The reaction mixture was then poured into a mixture of 400 ml. of 3-N sulphuric acid and 600 g. of ice, the ether layer was separated and washed with 5 o' aqueous sodium bicarbonate solution dried over sodium sulphate and concentrated in vacuo, yielding 200 g. of resinous 1,18 - di[21,61161 - trimethyl - cyclo hexadien - (11,31) - yl - (11)]-3,7,12,16 - tetra methyl - 8,11 - dihydroxy - octadecahexaen (2,4,6,12,14,16)-ine-(9). 1B) 16 g. of magnesium and 110 g. of n-hexyl bromide were reacted in 330 ml. of absolute ether, thereby forming an ethereal solution of n-hexyl magnesium bromide. This Grignard solution was stirred for 24 hours in an atmosphere of acetylene. Two layers were formed. The upper layer was separated off. The lower layer was mashed once with 100 mi. of absolute diethyl ether, and to the washed material was addrd 200 ml. of absolute diethyl ether, and then a solution of 80 g. of 8-[21,61,61-trimethyl-cyclohexen-(21)ylidene - (11)] - 2,6 - diemthyl - octatrien (2,4,6)-al-(1) in 200 ml. of absolute diethyl ether was added quickly. The mixture was heated under reflux for 3 hours, while stirring, in a nitrogen atmosphere. Then the reaction mixture was cooled, Foured into a mixture of 75 g. of ammonium chloride and 175 g. of ice-water, and the whole was stirred well for 10 minutes. The ether layer was separated, washed thrice (each time with 200 ml. of water)

and the washed ethereal solution was dried over sodium sulphate. The ether was driven off, yielding 87 g. of yellow, resinous 1,18 - di[21,61,61 - trimethyl - cyclo hexen - (21) - ylidene - (11)] - 3,7,12,16 tetramethyl - 8,11 - dihydroxy - octadeca hexaen-(2,4,6,12, 14,16)-ine-(9), having an absorption maximum in the ultraviolet spectrum at 349.5 m (in petroleum ether). 2E) Dry, acetone-free acetylene was introduced into a solution of 3 g. of lithium in 1200 ml. of liquid ammonia, until there was no further reaction. Then, while stirring vigorously, a solution of 100 g. of 8-[2S,6',6l- trimethyl - cyclchexen - (21) - ylidene - (11)] 2,6-dimethyl-octatrien-(2,4,6)-al-(1) in 400 ml. of absolute diethyl ether was added over a period of 20 minutes, and the reaction mixture was stirred thoroughly for 20 hours, with precautions to exclude moisture. Thereupon 50 g. of ammonium chloride was added in small portions, and the ammonia was permitted to evaporate 400 ml. of water was added, the ether layer was separated and washed with water and then dried over sodium sulphate and concentrated. The residual reddish oil was dried well in vacuo. There were obtained 108 g. of 10-[21,61,61-trimethylcyclohexen - (21) - ylidene - (11)] - 4,8 - di methyl-decatrien-(4,6,8)-in-(1)-ol-(3) as a viscous oil having an absorption maximum in the ultraviolet spectrum at 349 mp (in petroleum ether). Determination of active hydrogen according to the Zerewitinoff method showed, in the cold, one active hydrogen atom and, in the warm, two active hydrogen atoms. The last named compound (108 g.) was dissolved in 500 ml. of absolute diethyl ether and was added gradually, at 150 C.-200 C., while stirring, to a Grignard solution prepared from 18 g. of magnesium, 91 g. of ethyl bromide and 300 ml. of absolute diethyl ether. The reaction mixture was heated under reflux for one hour in a nitrogen atmosphere and then cooled with ice-water. A solution of 92 g. of 8-[21,61,61-trimethyl-cyclohexen-(21)ylidene - (11)] - 2,6 - dimethyl -octatrien (2,4,6)-al-(1) in 400 ml. of absolute diethyl ether was added at about 200 C. and the reaction mixture was heated under reflux for 3 to 4 hours in a nitrogen atmosphere. The reaction mixture was then poured into a mixture of 400 ml. of 3-N sulphuric acid and 600 g. of ice, the ether layer was separated and washed with 5% aqueous sodium bicarbonate solution dried over sodium sulphate and concentrated in vacuo, yielding 200 g. of resinous 1,18 - di[21,61,61 - trimethyl - cyclohexen (21) - ylidene - (11)] - 3,7,12,16 - tetramethyl 8,11 - dihydroxy - octadecahexaen - (2,4,6,12, 14,16)-ine-(9). STAGE 2 1) A solution of 19 g. of 1,18-di[21,61,61- trimethyl - cyclohexadien - (11,31) - yl (11)3 3,7,12,16 - tetramethyl - 8,11 - dihydroxy

octadacahexaen - (2,4,6,12,16) - ine - (9) in 38 ml. of toluene was added gradually to a well stirred mixture of 6.8 ml. of phosphorus oxychloride, 34 ml. of pyridine and 30 ml. of toluene, while cooling with ice-water. Then the reaction mixture was heated for one hour at 95 C., quickly cooled down and poured upon 300 g. of ice. The toluene solution was separated, washed twice with sulphuric acid (each time with 200 ml. of 3-N sulphuric acid) and then twice with aqueous sodium bicarbonate (each time with 200 ml. of 5% aqueous sodium bicarbonate solution). The washed toluene solution was dried over sodium sulphate and the solvent was removed under a water-pump vacuum. The crystalline residue was washed with a little petrol leum ether and was recrystallized from a mixture of methylene chloride and methanol. The red-violet crystals of 3,4;31,41;15,151-trisdehydro-betacarotene so obtained had a melting point 165 C.-1670 C. and ultraviolet absorption maximum at 449 m,a (in petroleum ether solution). 2) A solution of 10 g. of 1,18-di[21,61,61trimethyl - cyclohexen - (21) - ylidene - (11)] 3,7,12,16 - tetramethyl - 8,11 - dihydroxy octadecahexaen - (2,4,6,12,16) - ine - (9) in 90 ml. of toluene was added gradually to a well stirred mixture of 6 ml. of phosphorus oxychloride, 43 ml. of pyridine and 50 ml. of toluene while cooling with ice-water. Then the reaction mixture was heated for one hour at 95 C. and quickly cooled down and poured upon 300 g. of ice. The toluene solution was separated washed twice with sulphuric acid (each time with 200 ml. of 3-N sulphuric acid) and then twice with sodium bicarbonate solution (each time with 200 ml. of 5% aqueous sodium bicarbonate solution). The washed toluene solution was dried over sodium sulphate and the solvent was removed under a water-pump vacuum. The residue was extracted with petroleum ether and the petroleum ether extract was concentrated, thereby yielding crude 3,4; 31,41;15,151-trisdehydro-betacarotene. Upon recrystallisation from a mixture of methylene chloride and methanol, the purified material formed redviolet crystals, m.p. 165 C.-167 C.; ultraviolet absorption maximum at 449 m (in petroleum ether solution). 3)1 g. of 1,18-di[21,6l,6l-trimethyl-cyclo- hexadien - (11,31) - yi - (11)] - 3,7,12,16 - tetramethyl - 8,11 - dihydroxy - octadeca hexaen-(2,4,6,12,14,16)-ine-(9) was dissolved in 20 ml. of diethyl ether, and the solution was mixed with 2 ml. of ethanolic hydrogen chloride containing 23.7% by weight hydrogen chloride and 4 ml. of ethanol. The mixture was allowed to stand for 2 hours at ca 20 C. and then for an additional period of 18 hours at 0 C.-5 C. The crystals formed were filtered off with suction, washed with methanol and with petroleum ether and then dried. There were obtained 0.8 g. of 3,4;31,41;15,151 - trisdehydro - betacarotene, m.p. 165 C. STAGE 3

0.75 g. of 3,4;31,41;15,151 - trisdehydro betacarotene in 20 ml. of toluene was shaken in a hydrogen atmosphere at 20 C. in the presence of 0.2 g. of palladium/lead/calcium- carbonate catalyst /Lindlar, Helvetica Chimica Acta, 1952, 35, 450/ and 0.05 ml. of quinoline until one molar proportion of hydrogen was taken up. The catalyst was then filtered off and the solvent was removed in a high vacuum. The residue was crystallized from a mixture of methylene chloride and methanol, thereby yielding 15,151-monocis 3,4;31,41 - bisdehydro - betacarotene as dark red to violet crystals; m.p. 1900 C. (after softening and resolidification at 1300 C.- 140 C.); ultraviolet absorption maxima at 366 m (" cis peak ") and 467 m (in petroleum ether solution). STAGE 4 A suspension of 5 g. of 15,151-monocis 3,4;31,41-bisdehydro-betacarotene in 30 ml. of petroleum ether (b.p. 80 C.-100 C.) was heated under reflux for 22 hours in a liitro- gen atmosphere. Then the mixture was cooled and the crystalline precipitate was filtered off. The solid was recrystallized from a mixture of methylene chloride and petroleum ether (alternatively, from methylene chloride/methanol). The blue-violet crystals of all-trans 3,4;31,41-bisdehydro-betacarotene so obtained had a melting point of 190 -190 C., and showed an absorption maximum in the ultraviolet spectrum at 471 m (in petroleum ether solution). What we claim is: 1. 3,4;31,41;15,15 - trisdeydro - beta carotene and 15,151-monocis 3,4;31,41-bisdehydro-betacarotene, 2. A process for the manufacture of the dehydro-betacarotenes claimed in Claim 1 whereof, which process comprises condensing acetylene with 8-[21,61,61-trimethyl-cyclohexadien - (11,31) - yl - (11)] - 2,6 - dimethyl octatrien-(2,4,6)-al-(1) or 8-[21,61,61-trimethylcyclohexen - (21) - ylidene - (11)] - 2,6 - di methyl-octatrien-(2,4,6)-al-(1) in a metalorganic reaction, subjecting the resulting 1,18 di[21,6l,6l - trimethyl - cyclohexadien - (11,31) yl - (11)] - 3,7,12,16 - tetramethyl - 8,11 dihydroxy - octadecahexaen - (2,4,6,12,14,16)ine-(9) or 1,18 - di[21,61,61 - trimethyl cyclohexen - (21) - ylidene - (11)] - 3,7,12,16 tetramethyl - 8,11 - dihydroxy - octadeca hexaen - (2,4,6,12,14,16) - ine - (9) to bilateral allyl rearrangement and dehydration and, if desired, partially hydrogenating the resulting 3,4;31,41;15,15 l-trisdehydro-betacarotene at the triple bond to obtain 15,151-monocis 3,4;31,41-bisdehydro-betacarotene. 3. A process in accordance with Claim 2, wherein the said condensation is carried out stepwise by first condensing acetylene with approximately one molar proportion of the aldehyde initial material in a metal-organic reaction and condensing the 1S[21,6l,6l-tri- methyl -

cyclohexadien - (11,31) - yl - (11)] 4,8 - dimethyl - decatrien - (4,6,8) - in - (1) ol - (3) or 10 -[2l,6l,6l - trimethyl - cyclo hexen - (21) - ylidene - (11)] - 4,8 - dimethyl decatrien - (4,6,8) - in - (1) - ol - (3) so obtained with a further approximately molar proportion of the said material in a metalorganic reaction. 4. A process in accordance with Claim 2 or Claim 3, wherein the bilateral allyl rearrangemcnt and dehydration is brought about by heating the product of the first stage in an inert solvent with about two molar proportions of phosphorus oxychloride in the pre- sence of an organic tertiary base or by react ing same with a hydrogen halide at a low temperature. 5. A process in accordance with any one of the preceding process claims, wherein the partial hydrogenation is carried out using elemental hydrogen in the presence of a hydrogenation catalyst which selectively catalyses the conversion of a triple to a double bond. 6. A process in accordance with any one of the preceding process claims, which includes the further step of isomerizing the 15,151monocis 3,4;31,41-bisdehydro-betacarotene by heating or irradiating same or treating same with iodine to produce all-trans 3,4;3,4-bisdehydro-betacarotene. 7. A process in accordance with Claim 6, wherein the isomerization is brought about by heating a suspension of the 15,15l-monocis 3,4;31,41-bisdehydro-betacarotene in an organic liquid vehicle. 8. A process for the manufacture of the substances claimed in Claim 1 hereof and their conversion into all-trans 3,4;31,41-bisdehydrobetacarotene, substantially as described with reference to the example.