14aWr Research Vol. 12. pp. 299 to 301 0043-1354/78/0401-0299102.00/0 © Pergamon Press Ltd. 1978. Printed in Great Britain

SEPARATION A N D DETERMINATION OF MINERAL, ANIMAL A N D VEGETABLE OILS IN WATER WITH THE USE OF

MOLECULAR SIEVE 5A

M . UCHIYAMA

Gunma Research Centre for Environmental Science, 3-21-19, Iwagami-cho, Maebashi, Gunma, Japan

(Received 25 September 1977)

Al~tract--Mineral, animal and vegetable oils in water were separated and determined by the infrared method with the use of molecular sieve 5A (MS 5A). After being extracted by carbon tetrachloride, the extract were treated with MS 5A. Mineral oil was not adsorbed on MS 5A, but animal and vegetable oils were. Oils extracted with carbon tetrachloride were measured by the peak at 2950 era-t due to the vibration of the CH groups.

INTRODUCTION With the growing use of oil products, the problems of water pollution by hydrocarbons and the measur- ing of hydrocarbon content has become very impor- tant. Many methods of measuring hydrocarbon con- tent have been reported (Rosen et al., 1955; Simard et al., 1951; Webber et al., 1952; Mallevialle, 1974; Saito et al., 1972).

Suzuki et al. (1974) reported the separable deter- mination of mineral oil, fatty acid and fatty oil dis- pe r~d in water with the method of solvent extrac- tion-infrared analysis.

The new method using molecular sieve 5A (MS 5A) reported here is the method of separation and deter- mination of the mineral oil and animal and vegetable oils in water.

EXPERIMENTAL

Analytical procedure

The flow sheet of the analytical procedure is shown in Fig. I.

(I) 10g sodium chloride and 10 ml carbon tetrachloride were added to 350 ml sample water in a 500 ml separable funnel.

(2) The funnel was shaken for 5 rain to separate the car- bon tetrachloride layer.

(3) After shaking the carbon tetrachloride layer with 1 g sodium sulfate anhydrous, the carbon tetrachloride layer was filtered with a filter paper.

(4) After adjusting the volume 10 ml with carbon tetra- chloride, the solution may be used for infrared analysis. (Determining the concentration of total oil.)

(5) After analysing the concentration of total oil, the two carbon tetrachloride solution was mixed and 3 g MS 5A were added to the mixture.

(6) After standing the solution with MS 5A at room temperature for 1.5 h with occasional shaking, the solution was used for infrared analysis. (Determining the concen- tration of mineral oil.)

Oils used in this experiment

Mineral oil--heavy oil, machine oil, engine oil, spindle oil, pump oil (for a vacuum pump).

Animal oil--beef tallow, lard, whale oil.

299

Vegetable oil--rape seed oil, soy bean oil, cotton seed oil, olive oil.

Each oil was solved in carbon tetrachloride and its con- centration was I g 10ml -~ CCI4 (0.1 mg/d-t) . Molecular sieve

The molecular sieve used in this experiment was type 5A, 1/16 inch pellets (Linde Co.). MS 5A was heated to 400-500°C and maintained at that temperature for 3 h in the electric furnace and cooled to room temperature in a desiccator.

Cells for infrared analysis Cells for infrared analysis used in this experiment were

l0 m quartz cells usually used in the ultra.violet analysis.

RESULTS AND DISCUSSION

Extraction with carbon tetrachloride

Suzuki reported that the oils in water could be extracted with a small amount 0/100, v/v) of carbon

__1__ Water

Sample

J m Sodium chloride

Carbon --H tetrachlor ide [

(Shaking) ! Carbon tetrachlor ide

J= Sodium sulfate ~anhydrous

(Filtrate with f i l ler paper)

( ( i.r analysis ) ----'~Concem'rationJ

J - - ¢ | o f total oil J

MS-SA

(Adsorption)

I ana,ysis ,

[ o f mineral oil / Fig. 1. Flow sheet of MS 5A method.

300 M. UCHIYAMA

6 0

0~

c u 4-

E

o

8 0

4 0

2 0

>, 4-

c

o~

J !

I I 3 2 0 0 2 8 0 0

F r e q u e n c y , c m '

Fig. 2. The i.r. spectrum of oil.

I - -

E

6

~- 0 5 - - 3 "o o I g Z

0 - -

0 2 4 6

Added o i l , m g

Fig. 4. The absorptive capacity of MS 5A. O, beef tallow; A, lard; I~1, whale oil; I-1 rape seed oil; ¢, cotton seed

oil; ~, soy bean oil; /h olive oil.

tetrachloride, if 20g of sodium chloride was added to 700 mt of water.

In the experiment reported here, 10ml carbon tetrachloride and 10 g of sodium chloride were added to 350 ml of water. After extracting, l g sodium sulfate anhydrous was added to the carbon tetrachloride layer and the carbon tetrachloride layer was filtered with a filter paper. This procedure had very little effect on the recovery of oils. Machine oil, 99.0%; pump oil, 96.9'~,; heavy oil, 102.5%; engine oil, 100.8'~o; spindle oil, 97.0°i',; whale oil, 99.2%; beef tal-

0

3

~ 3 - -

c o z

~aL zJ

, 0 5 2 5

Adsorption t i m e , h

F i g . 3. T h e r a t e o f a d s o r p t i o n o f o i l s o n M S 5 A . O , h e a v y oil: D. pump oil; ~, machine oil; /x, engine oil; I~l, spindle

oil: A, lard: &. soy bean oil.

15

B ; 1 2 3

I 0

r' 1 i 0 5 I0

0iI, p p r n

Fig. 5. The standard curves. 1, engine oil, pump oil; 2, lard, beef tallow, whale oil; 3, machine oil, olive oil; 4, rape seed oil, cotton seed oil; 5, heavy oil, soy bean oil; A, oleic acid; B, decane; C, palmitic acid; D, stearic acid.

Separation and determination of mineral, animal and vegetable oils

Table 1. Analytical results of oils in pure water

301

Mineral oil added Vegetable oil added Animal oil added Total oil Mineral oil (mg) (mg) (mg) (mg) (mg)

rape soy beef machine pump heavy engine spindle seed cotton olive bean tallow lard whale added detected added detected

1.0 1.0 0.5 0.5 0.5 0.5 4.0 3.81 2.0 2.28 1.0 1.0 0.5 0.5 0.5 0.5 4.0 3.65 2.0 1.91

1.0 1.0 0.5 0.5 0.5 0.5 4.0 3.73 2.0 2.14 1.0 1.0 0.5 0.5 0.5 0.5 0.5 0,5 0.5 5.5 5.90 2.0 1.93

1.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 5.5 5.66 2.0 1.93

Table 2. Analytical results of oils in river waters and waste waters

Mineral oil added Vegetable oil added Animal oil added Total oil Mineral oil Water* (mg) (rag) {rag) ling) (mg)

rape soy beef machine pump heavy engine spindle seed cotton olive bean tallow lard whale added detected added detected

A 0.5 0.5 0.5 0.5 0.5 0.5 0.5 3.5 3.32 1.5 1.48 B 0.5 0.5 0.5 0.5 0.5 0.5 0.5 3.5 3.28 1.5 1.58 C 0.5 0.5 0.5 0.5 0.5 0.5 0.5 3.5 3.36 1,5 1.46 D 0.5 0.5 0.5 0.5 0.5 0.5 0.5 3.5 3.32 1:5 1.46

* A, water from river A; B, water from river B; C, effluent of the sewage treatment works C; D, effluent of sewage treatment works D.

low, 96.3%; lard, 99.3%; rape seed oil, 99.0%; olive o / , oil, 100.9/o, soy bean oil, 98.8%; cotton seed oil,

103.0%.

Infrared spectra of oils in carbon tetrachloride

The infrared spectra of oils is of the type illustrated in Fig. 2. The peaks of high intensity due to CH, CH2, and CH3 in the 2800-3100cm -~ range are characteristic of the aliphatic chains and can therefore be used to measure oil content. The peak of 2950 cm-~, the peak of the highest intensity, was used in this experiment.

MS 5A treatment

Three grams of MS 5A were added to the carbon tetrachloride solution of each oil. The concentration of each oil was 1.0 mg l0 ml - ~ CCI 4. The solution with M S 5 A was stored at room temperature with the occasional shaking. Figure 3 shows the relationship between the adsorption time and the quantity of non- adsorption oil. Mineral oils were not adsorbed on MS 5A or the rate of adsorption was very slow. But the rate of adsorption of animal and vegetable oils was very fast and they were adsorbed perfectly on MS 5A for about one hour. Other animal and vege- table oils were just the same as lard and soy bean oil (Fig. 3). The difference in this adsorption rate is very useful for separating mineral oils from animal and vegetable oils.

Figure 4 shows the adsorptive capacity of MS 5A. 3g M S 5 A and 1-6rag of each oil were added to 10ml carbon tetrachloride and the solution was stored at room temperature for 1.5 h with occasional shaking. Figure 4 shows that the adsorptive capacity of MS 5A was 2 mg oil 3 g - ~ MS 5A. This shows that if the quantity of oil was higher than 2 rag, the carbon tetrachloride solution of oils should be diluted before MS 5A treatment.

Standard curve

The standard curves of oils are shown in Fig. 5. The linearity of the points obtained was satisfactory in each oil. In most cases where the exact nature of the pollution is unknown, the kind of oil used as the standard material is very important. Four chemical reagents were studied as the standard materials. From Fig. 5 oleic acid seems to be most suitable for all types of oils.

Application to some cases

The definite quantity of each oil was added to 350 ml pure water, river water and effluent of sewage treatment works and these samples were analysed. The river waters and effluents of sewage treatment works were analysed but did not contain any oils.

Tables 1 and 2 show the analytical results of each case. These analytical results were obtained by the use of the standard curve of oleic acid.

REFERENCES

Mallevialle J. (1974) Measurement of hydrocarbons in water: Application to cases of surface water pollution. Water Res. 8, I071-1075.

Rosen A. A. & Middleton F. M. (1955) Identification of petroleum refinery waters in surface waters. Analyt. Chem. 27, 709-794.

Saito T., Hagiwara K. & Ozawa Y. (1972) Determination of trace amounts of dispersed oil in waste water by sol- vent extraction infrared analysis. Japan Analyst 21, 1235-1237.

Simard R. G., Hasegawa I., Bandaruk W. & Headington C. E. (1951) Infrared spectrophotometric determination ofoil and phenol in water. Analyt. Chem. 23, 1384-1387.

Suzuki R., Yamaguchi N. & Matsumoto R. (1974) Deter- mination of trace amounts of dispersed oil in waste water by solvent extraction-infrared analysis. Japan Ana- lyst 23, 1296-1303.

Webber L. A. and Burks C. E. (1952) Determination of light hydrocarbons in water. Analyf. Chem. 24, 1086-1087.

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