OxyChemMuriatic AcidHandbook 1 of 34

Page

·· Introduction . . . . . . . . . . . . . . . . . . . . . . . . . .2

·· Principal Uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

·· Safety in Handling Muriatic Acid . . . . . . . . . . .5

·· Unloading & Handling Muriatic Acid . . . . . . . .9

·· Equipment For Handling Muriatic Acid . . . . .15

·· Technical Data . . . . . . . . . . . . . . . . . . . . . . .20

·· Dilution Calculations . . . . . . . . . . . . . . . . . .32

·· Methods of Analysis . . . . . . . . . . . . . . . . . .34

THE INFORMATION PRESENTED HEREIN WAS PREPARED BY TECHNICAL PERSONNEL AND IS TRUE AND ACCURATE TO THE BESTOF OUR KNOWLEDGE. OXYCHEM DOES NOT MAKE ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULARPURPOSE, EXPRESS OR IMPLIED, REGARDING PERFORMANCE, STABILITY OR ANY OTHER CHARACTERISTIC. THE INFORMA-TION CONTAINED HEREIN IS NOT TO BE CONSTRUED AS AN EXPRESS WARRANTY CONCERNING THE PERFORMANCE, STABIL-ITY OR ANY OTHER CHARACTERISTIC OF ANY OXYCHEM PRODUCT. THIS INFORMATION IS NOT INTENDED TO BE ALL-INCLUSIVEAS TO MANNER OR CONDITIONS OF USE. HANDLING, STORAGE, DISPOSAL AND OTHER ACTIVITIES MAY INVOLVE OTHER ORADDITIONAL LEGAL, SAFETY OR PERFORMANCE CONSIDERATIONS. WHILE OUR TECHNICAL PERSONNEL WILL RESPOND TOANY QUESTIONS REGARDING SAFE HANDLING AND USE PROCEDURES, SAFE HANDLING AND USE REMAINS THE RESPONSI-BILITY OF THE CUSTOMER. NO SUGGESTIONS FOR USE ARE INTENDED AS, AND NOTHING HEREIN SHALL BE CONSTRUED AS ARECOMMENDATION TO INFRINGE ANY EXISTING PATENT OR TO VIOLATE ANY FEDERAL, STATE OR LOCAL LAW.Occidental Chemical Corporation 2000

HClHCl

Muriatic AcidHandbook

OxyChemfifiOxyChem is a registered trademark of Occidental Chemical Corporation.

Hydrochloric Acid

ForewordThis handbook outlines the methods for

handling, storing, preparing and using muri-atic acid. It includes information on the man-ufacture, physical properties and analyticalmethods for muriatic acid.

Additional information and contacts can befound on the internet at www.oxychem.com

Occidental Chemical CorporationBasic Chemicals GroupOccidental Tower5005 LBJ FreewayDallas, TX 75244

Muriatic acid, or HCl, are com-monly known names forhydrochloric acid (CAS Number7647-01-0). It is a highly corro-sive solution of hydrogen chloride(HCl) in water. Its concentration isusually expressed in DegreesBaumé (abbreviated °Bé). It iscommonly supplied in 20° Béstrength, although a wide varietyof other strengths are possible. Inconcentrations greater than 8.5°Bé (12.5%), HCl emits strongfumes with a pungent odor ofhydrogen chloride. Muriatic acidis colorless as a pure solution,although traces of iron, chlorineor organic matter will impart ayellowish color.

Concentrated muriatic acid isone of the strongest acids known.It readily attacks all of the com-mon metals to yield hydrogen asa by-product. Extreme cautionshould be taken as certain con-centrations of hydrogen in airmay be highly explosive.Solutions of muriatic acid arecapable of causing severe fleshburns and its vapors are irritatingto the skin, eyes and mucousmembranes. See the appropriateMSDS or the safety sections ofthis publication.

OxyChem markets by-productmuriatic acid from Niagara Falls,N.Y. This acid is made during thechlorination of organic chemicalsas shown below. The resultantquality of the muriatic acid maylimit its use in some applications.

Introduction2 of 34

R-H + CI2 R-CI + HCl(R-H = Hydrogen Containing Organic Substrate)

(i.e. toluene)

3 of 34

PICKLING & METAL CLEANING

Muriatic acid is used by thesteel industry for both continuousand batch pickling of hot rolledsteel sheeting, wire, rod, pipe andother steel products. Muriatic acidhas superior performance overother acids for this service, there-by resulting in its single largestapplication. Pickling removes millscale and cleans the steel prior toit being further treated; e.g., gal-vanizing, coating with tin, plasticor other materials. The muriaticacid is usually diluted andinhibitors added prior to pickling.This minimizes over reaction ofthe acid on the steel and thepotential for excessive fuming.

ETCHING

Muriatic acid is used as anetching medium for the chemicalmilling of aluminum, magnesium,steel and titanium.

CHEMICAL PROCESSING &MANUFACTURING

Muriatic acid plays a prominentrole in the production of commer-cially significant inorganic andorganic chemicals. It may beused as a raw material for asource of chlorine, as a catalystin organic synthesis, or to forminorganic chlorides in the pres-ence of metals having a positiveoxidation potential. Muriatic acidhas widespread use in the manu-facture of products such as vinylchloride, chlorinated solvents,chloroprene, titanium dioxide,metal chlorides, silica gel, alkylchlorides from olefin, and chlo-rides from alcohols.

Muriatic acid is frequently usedas a neutralizing agent for chemi-cal processes and waste watertreatment. Sludge and hard waterscale may also be dissolved fromprocess equipment and boilersusing inhibited HCl.

PETROLEUM PRODUCTION

Muriatic acid is used for acidifi-cation (activation) of wells in theproduction of petroleum toincrease the output of both gasand oil. The introduction of inhib-ited HCl into wells acts to dis-solve surrounding porous rock,such as limestone and dolomite,thereby creating channelsthrough which oil can flow morefreely. This, in turn, increases thetransmission of oil or gas to thebottom of the well. Additives tothe HCl often improve the pene-tration capabilities.

In addition to the above men-tioned application, HCl is alsoused to remove iron sulfide scaleon refinery and well-head equip-ment.

CERAMIC MANUFACTURING

Muriatic acid is used in themanufacture of glazes to helpkeep frit in suspension. Raw claymay also be treated with HCl toeliminate iron oxide, calcium,magnesium and iron carbonates.

LEATHER MANUFACTURING

Following depilating, hides canbe delimed and given a mildlyacidic character through soakingand paddling in a muriatic acidsolution. In this application,

traces of iron must first beremoved from the acid by ionexchange. HCl is also an ingredi-ent of tanning and dying liquorsusing mineral salts, i.e. chrometanning by the double-bathmethod.

MINING & METALLURGY

The leaching or “wet method” inextractive metallurgy utilizes HClto isolate valuable metallic ele-ments, including germanium,manganese, radium, tantalum,tungsten and vanadium from vari-ous high grade ores. It may alsobe used for ore reduction in therecovery of iron from low gradeiron ore.

Muriatic acid is reacted withphosphate rock to produce phos-phoric acid. It is also used in theproduction of alumina from baux-ite and laterite.

High purity magnesium is pro-duced using HCl in an electrolyticprocess with sea water.

PAINT, VARNISH, INK & DYE PRODUCTION

Muriatic acid is an ingredient ofprinting and writing inks. It is alsoa reagent in the preparation ofpaint pigments, dyes and dyeintermediates.

Principal Uses

4 of 34 Principal Uses

PAPER MANUFACTURING

Muriatic acid is used to setmelamine resins for improvedpaper wet strength. The papermanufacturing equipment is alsooften cleaned with a solution con-taining HCl.

Prior to coating with a light sen-sitive solution, grained lithograph-ic plates are counter-etched in asolution of HCl. This removes thedirt and metal oxides andincreases the plate’s affinity forthe grease in the developing ink.

RUBBER MANUFACTURING

Chloroprene is produced whenmuriatic acid is combined withvinyl acetylene in the presence ofa catalyst. This is then used asan intermediate for the productionof neoprene rubber. HCl is alsoused in a process to coagulatelatex rubber and in rubber recla-mation.

SOAP MANUFACTURING

Muriatic acid is used in aprocess to treat soap lye crudefor the recovery of glycerol. It isalso used as a neutralizing agentin the production of specific syn-thetic detergents.

TEXTILE MANUFACTURING

Residual alkali is neutralized incotton piece goods in the souringprocess immediately prior tobleaching.

WATER PURIFICATION

Muriatic acid is often used inthe backwashing of filter beds toclear traces of iron from the sand.

RESIDENTIAL USES

Relatively dilute solutions ofmuriatic acid are often found inhardware stores for residentialapplications. Two common usesare etching of concrete prior topainting and pH reduction inswimming pools.

FOOD PROCESSING

Muriatic acid is often used inthe processing of corn syrup andsodium glutamate.

5 of 34

Safety In HandlingMuriatic Acid

SAFETY PRACTICES

Read the MSDS before use.

An operation where muriaticacid is handled can ensure mini-mum employee exposure byusing properly designed systemsand insisting that employeesobserve the following safety prac-tices:

• Muriatic acid is highly corrosiveand contact with the skin oreyes may lead to serious injury.Protective clothing and equip-ment should be provided toeach employee routinelyexposed to the dangers ofchemical contact. It should bemandatory that this equipmentbe worn when direct contactwith liquid or acid vapor is pos-sible. This includes chemicalsafety goggles, face shield,hard hat, rubber gloves, rubberboots and protective acid resis-tant clothing. Use of suchequipment is not intended as asubstitute for proper operationor maintenance practices.

• Breathing of muriatic acid vaporshould be avoided. Use onlywith adequate ventilation or usea NIOSH approved respiratorwith an acid gas cartridge witha dust, fume and mist filterwhere airborne concentrationsare expected to exceed expo-sure limits or when symptomshave been observed that areindicative of over exposure.

• Avoid contact with the body. Ifcontacted, wash thoroughly withlarge quantities of water andconsult a physician.

• Emergency shower and eye-wash facilities should be inclose proximity to where muriat-ic is handled. Those locatedoutdoors should be designedfor year round service.

• Do not store in unlined contain-ers. Leaking containers should be moved outdoors or toa well ventilated area until con-tents can be transferred to asuitable container for properdisposal.

• Dike and vent storage tanks.

• Avoid spilling or splashing muri-atic acid. If spillage hasoccurred, clean up immediatelyand dispose of in accordancewith all federal, state and localregulations.

EFFECTS OF OVEREXPOSURE

Acute:

HCl is strongly irritating andcorrosive to the eyes, skin, mouthand digestive system. Vapors areirritating to the respiratory tract;excessive exposure may causemore severe symptoms includingpulmonary edema.

The local dermal effect mayconsist of multiple areas of super-ficial destruction of the skin or ofprimary irritant dermatitis.Similarly, inhalation of spray, mist,or vapor may result in varyingdegrees of irritation or damage tothe respiratory tract tissues andan increased susceptibility to res-piratory illness.

Chronic:

There are no known chronichealth effects.

Thermostatically controlledelectric heat tracing is preferredfor safety showers. Steam trac-ing should be avoided due tothe potential danger of over-heating the shower water.

• Muriatic acid containers shall beproperly identified and shallhave appropriate warninglabels.

• Keep heat, sparks, openflames, pilot lights, and lightedcigarettes away from the areaof use since toxic, corrosive andexplosive gases may beformed.

• Before any repairs on acid han-dling equipment are attempted,tanks, pipes, valves, etc.,should be drained and purgedwith water. The hazard of ahydrogen explosion is presentwhen cutting into empty acidlines or empty tanks. This haz-ard may be minimized by forc-ing a stream of N2, CO2 or otherinert gas into the line.

• Keep non-vented containerstightly closed when not in use.

• Store in a cool, ventilated areaaway from flammable sub-stances and oxidizing materials,particularly nitric acid and chlo-rates.

• Open containers carefully toavoid spurting.

• DO NOT ADD WATERDIRECTLY TO MURIATICACID. If dilution is desired,slowly add acid to water. Do notmix with alkalies such as sodi-um hydroxide (caustic soda) oralkali metals to avoid possibleviolent reaction.

Safety In HandlingMuriatic Acid6 of 34

FLAMMABILITY

Unusual Fire & ExplosionHazards

Muriatic acid is non-flammableand non-explosive under normalconditions of use. However, reac-tion of this acid with most metalswill produce hydrogen gas which isflammable and may be extremelyexplosive under certain conditions.DO NOT allow the use of openflames, open lights, matches orsmoking in or around areas wheremuriatic acid is handled.

At high temperatures, this prod-uct can generate toxic and irritatinggases. If storage containers areexposed to excessive heat, over-pressurization and rupture of thecontainer can result. The use ofwater on this product should bediscouraged. Addition of watermay cause a violent reaction.

Extinguishing Media

Carbon dioxide, dry chemicaland foam may all be used in areaswhere muriatic acid is stored.

Special Fire FightingProcedures

Positive pressure, self-containedrespiratory protection should beprovided for fire fighters in build-ings or confined areas where muri-atic acid is stored.

REACTIVITY

Muriatic acid is stable under nor-mal conditions of use. However,hydrogen chloride gas exerts asignificant partial pressure and isreleased if this product is not in aclosed system. The amount ofhydrogen chloride gas releasedincreases as the temperature ofthe acid increases.

Muriatic acid reacts with mostmetals to produce hydrogen gas.When hydrogen gas is mixed withair, a fire or explosion could resultif the mixture is ignited. Muriaticacid can react violently with activemetals and alkali compounds. DONOT ADD WATER DIRECTLY TOTHIS PRODUCT because a signif-icant amount of heat can be gen-erated and spattering may occur.Muriatic acid, however, may safelybe diluted by slowly adding it towater with mixing. Reaction ofmuriatic acid with strong oxidizingagents may release chlorine gas.

EMPLOYEE TRAINING

Safe handling of muriatic aciddepends a great deal on the effec-tiveness of employee education,proper training in safe practices,the use of safety equipment andgood supervision.

Training classes and drills for bothnew and veteran employeesshould be conducted at leastannually to maintain a high degreeof safety awareness in handlingprocedures. Employees should beinformed of the potential hazardsthat may result from improper han-dling practices. They should becautioned to prevent spills andthoroughly instructed in the emer-gency spill response plans in theevent that a spill should occur.

Employee training and drillsshould include (but are not limitedto) the following:

1. The location, purpose and useof fire fighting equipment.

2. The location, purpose and useof personal protective equip-ment.

3. The location of safety showersand eye washes.

4. Instructions to avoid theinhalation of vapors and directcontact with muriatic acid.

5. Instructions to properly reportall cases of equipment failure.

6. The location of appropriateMaterial Safety Data Sheet(MSDS). Review their contentso the information is under-stood.

7. Procedural instructions on thecompany’s Spill ResponsePlan.

7 of 34Safety In HandlingMuriatic Acid

PROTECTIVE EQUIPMENT

OSHA requires employers tosupply suitable protective equip-ment for employees. When han-dling muriatic acid, the followingprotective equipment is recom-mended:

• Wear a NIOSH approved respi-rator with an acid gas cartridgewith a dust, fume and mist filterwhere airborne concentrationsare expected to exceed expo-sure limits or when symptomshave been observed that areindicative of overexposure.

• Wear suitable chemical splashgoggles for eye protectionduring handling of muriaticacid in any form. The gogglesshould be close fitting and pro-vide adequate ventilation to pre-vent fogging, without allowingentry of liquids.

• The use of a face shield may beappropriate when splashing canoccur.

• Wear chemical resistant gloves,such as rubber, neoprene, nitrileor PVC to protect hands whilehandling muriatic acid. Glovesshould be long enough to comewell above the wrist. Sleevesshould be positioned over theglove wrists.

• Wear chemical resistant clothingand rubber boots for protection ofthe body. Impregnated vinyl orrubber suits are recommended.

• Wear hard hat for some protec-tion of the head, face & neck.

FIRST AID

Muriatic acid is highly corrosiveand contact with the skin or eyesmay lead to serious injury.Immediate action, as listed below,should help to minimize theseverity.

Eye:

Immediately, then seek medicalattention. Immediately flush eyeswith large amounts of water for atleast 15 minutes, holding lidsapart to ensure flushing of theentire eye surface. Washing eyeswithin seconds is essential toachieve maximum effectiveness.Seek medical attention immedi-ately thereafter. Muriatic acidrapidly causes severe irritation ofthe eyes and eyelids. If the acidis not quickly removed by thor-ough irrigation with water, theremay be prolonged or permanentvisual impairment or total loss ofsight. Hydrogen chloride gasescaping from an aqueous solu-tion is immediately irritating to theeyes.

Skin:

Muriatic acid is irritating andcorrosive to the skin and cancause severe burns if not prompt-ly washed off with copious quanti-ties of water. Immediately washcontaminated areas with plenty ofsoap and water for at least 15minutes. Remove contaminatedclothing and footwear. Seek med-ical attention immediately. Do notattempt to neutralize the acid withalkaline solutions. Wash clothingbefore reuse and discardfootwear which cannot be decont-aminated. Repeated skin contactmay lead to the development ofdermatitis.

Inhalation:

Remove to fresh air as quicklyas possible; if breathing is diffi-cult, have trained person admin-ister oxygen. If respiration stops,have a trained person administerartificial respiration. Get medicalattention. Inhalation of acid gas,mist, fog, or spray will causesevere irritation of the upper res-piratory tract, resulting in cough-ing, burning of the throat and a

choking sensation. If inhaleddeeply, edema of the lungs mayoccur. The irritating nature ofmuriatic acid vapor gives amplewarning of its presence in dan-gerous concentrations. Whendetected, promptly evacuate thecontaminated area.

Ingestion:

Never give anything by mouthto an unconscious person. Ifswallowed, DO NOT INDUCEVOMITING, although it mayoccur spontaneously. Give largequantities of water. If available,give several glasses of milk.Sodium bicarbonate, which wouldgenerate carbon dioxide, shouldnot be used. Keep airways clear.Seek medical attention immedi-ately.

Muriatic acid causes severeburns of mucous membranes ofthe mouth, esophagus, and stom-ach if swallowed. and can causenausea, vomiting and diarrhea.

Seek Medical AttentionImmediatelySPILL RESPONSE

In the event of a spill, restrictthe area keeping unnecessarypeople away and upwind of thespill area. All responding person-nel should be equipped with self-contained breathing apparatusand full protective clothing. Leaksshould be stopped to minimizethe spill. Diking should be used tocontain the spill and to preventthe acid from entering sewersand waterways. In the event of alarge spill, pump as much acid as

Safety In HandlingMuriatic Acid8 of 34

possible into a marked containerfor future reclamation or disposal.A water fog or spray may beused to help control vapors. Sodaash or lime should be readilyavailable for immediate neutral-ization of small spills andresidues from larger spills. Smallspills may also be absorbed withcompatible substances such assand or earth. Spills on reactiveor absorbent materials should beneutralized and picked up.NEVER FLUSH TO SEWER.When soda ash is used, ampleventilation should be provided.

Releases of muriatic acid to theenvironment which exceed theCERCLA Reportable Quantity(RQ) of 5000 pounds must bereported immediately to theNational Response Center, aswell as the State EmergencyResponse Commission and the

Local Emergency PlanningCommittee. Also, lesserreportable thresholds may beapplicable under state and localregulations.

National Response Center (NRC)

1-800-424-8802

Unloading and HandlingMuriatic Acid 9 of 34

All Department ofTransportation (DOT),Environmental Protection Agency(EPA), Occupational Safety andHealth Administration (OSHA),and other applicable regulationsshould be reviewed before han-dling hydrochloric acid. All regula-tions must be followed andshould be incorporated into awritten bulk unloading proce-dure.State and local authoritiesshould be contacted to ensurethat a facility meets all regionalrequirements. All employees han-dling muriatic acid should receiveproper training, be familiar withthe appropriate Material SafetyData Sheet and applicable regu-lations.

Storage facilities must bedesigned to minimize human andenvironmental exposure tohydrochloric acid and its fumes.When appropriate, personal pro-tective equipment must be used

by properly trained employees. Asafety shower and eye wash sta-tion should be readily available.(Also reference the Safety sec-tion of this document.)

SAMPLING ACID SHIPMENTS

All acid shipments should besampled and analyzed prior tounloading to ensure that productquality is acceptable. Clean glassor polyethylene bottles are suit-able for hydrochloric acid.Samples should be taken throughthe top of the trailer or tank car. Itis important that a representativesample be taken so that theanalysis is not erroneous due tofaulty sampling techniques.

A vacuum bottle, as shown inFigure 1, is one effective methodof obtaining a representativesample. In this method, a vacuumrated glass sample bottle is firstfitted with a two-holed neoprene

stopper. It is carefully put undervacuum through pinch clamp #1,using a vacuum pump or a rub-ber syringe bulb, and sealed. Thesampling dip tube is inserted intothe product through the top domeof the vessel. As pinch clamp #2is released, the muriatic acid willbe drawn into the bottle. Thesampling tube is then slowly lift-ed, thereby taking a representa-tive cross-section sample of thedelivery vessel. The sampling diptube and rubber tubing should bedisposed of properly after sam-pling is complete.

TANK CAR & T ANKTRAILER UNLOADING

The Department ofTransportation classifieshydrochloric acid as a corrosivematerial and requires that it be

Unloading & HandlingMuriatic Acid10 of 34

transported in DOT approveddelivery vessels. Tank cars mustconform to 103B-W or DOT 111A60W5 specifications. Tank trailersmust conform to DOT MC-310,MC-311, MC-312 or DOT-412specifications. All tank cars andtank trailers must have a corro-sive placard displayed on bothsides, front and rear of the tank.The United Nations identificationnumber for muriatic acid isUN1789. This number mustappear on all shipping papersand placards.

All tank cars and tank trailersused in transporting OxyChemmuriatic acid are top unloadingand are not equipped with bottomvalves. They are typically madeof steel with an acid resistant rub-ber coating to ensure delivery ofcontamination free product. Forthis reason, extreme care is nec-essary in the removal andreplacement of all dome fittings.Proper care of fittings duringloading and unloading operationsis essential.

All precautions and proceduresrecommended by the DOT rela-tive to spotting, blocking andunloading of bulk shipmentsshould be followed. Caution signsshould be placed at both ends ofthe delivery vessel beingunloaded. These signs should beleft up until the vessel is com-pletely unloaded and hoses dis-connected. Signs for tank carsshould be at least 12” x 15” insize and bear the words: “ST OP-TANK CAR CONNECTED”

The unloading area shouldhave a concrete pad with acidresistant coating. It should drainto a contained sump. This willminimize any environmentaleffects in the event of a spill andfacilitate a rapid cleanup.

Typical tank trailer deliveriesare 4,600 U.S. gallons (approxi-mately 45,000 lb. of 20° Be’)muriatic acid. The acid isunloaded through the tank trailerwell line usually via on-site com-pressed air supplied by the cus-tomer. If air is not available, thebuyer should request that thetractor be equipped with a com-pressor. The unloading of 4,600gallons usually takes betweenone and two hours at a pressureof 8-20 psig, depending upon dis-charge head and the distancefrom the tank trailer to the stor-age tank. An important disadvan-tage of pressure unloading is inthe event of an emergency itlacks the immediate shutoff con-trol available with an electricallydriven pump. Furthermore, thehighest point in the unloading lineand storage tank cannot be morethan 45 feet above the bottom ofthe delivery vessel,since themaximum unloading pressure isgenerally about 20 psig.

Be sure that the receiving tankis clearly labeled to receive thematerial in the delivery vessel.Check the receiving tank to makesure the safety vent works andthat adequate space is availablefor the quantity delivered.

Although tank trailers usuallycome equipped with one 25’length of 2” flexible transfer hose,it is often desirable to provide adedicated hose for this service.Unloading fittings on tank trailersare standard. The liquid transferhose should have a 2” four-holeflanged fitting for attachment tothe valve on the discharge line ofthe tank trailer. Acid resistant rub-ber, cross linked polyethylene orfluorocarbon lined hoses are suit-able for muriatic use. These maybe attached to a pivoting swivel

arm (Figure 2) for ease of con-necting. Note: The unloading lineon some trailers comes down towaist level for added safety.

The customer should providean adequate length of 1” rubberhose to supply a regulatedamount of air not to exceed 25psig. The line should be equippedwith a relief valve set at 25 psig,oil trap, water separator, shut-offvalve, pressure reducing valveset at about 20 psig, and a pres-sure gauge. Compressed air linesshould be free of pipe scale andcompressor oils to prevent prod-uct contamination. Tank trailersare equipped with a safety reliefassembly typically set for 30 to45 psig. The hose may beequipped with a quick disconnectfitting for easy attachment (Figure3). Notify your OxyChemCustomer Service Representativeif this is desired.

Unloading & HandlingMuriatic Acid 11 of 34

Except for the difference insize, tank car deliveries are madeand emptied in the same fashionas tank trailers. Deliveries aregenerally made in 20,000 gallon(180,000 lb.) quantities. The cus-tomer is responsible for supplyingthe necessary hoses, valves andany other fittings. A Teflon® lined2” flanged plug valve and a suit-able length of 2” acid resistantflanged flexible hose should beused for this purpose. The carsare generally equipped with a l00psig rated composite rupturedisc.

Car fittings are standard andthere are no bottom unloadinghook-ups. Similar to the trailers,cars are generally unloadedusing clean compressed air at 20psig (Figure 4)

After the delivery vessel isempty, all unloading lines shouldbe thoroughly drained or blownclear prior to disconnecting. Allplugs, caps and flanges must bereplaced and valves closed tightlybefore the vessel is released.

12 of 34Unloading & HandlingMuriatic Acid

13 of 34Unloading & HandlingMuriatic Acid

UNLOADING PROCEDURES

1. Only responsible, well-trainedand well-supervised employ-ees should be entrusted withthe unloading of muriatic acid.A worker should be presentduring the entire time ofunloading and it should pro-ceed only during daytime orwith adequate lighting. A writ-ten copy of the proceduresshould be readily available.

2. The operation should be con-ducted with no emission ofmuriatic acid fumes or liquid.However, because of possibleaccidental emissions, workersresponsible for unloadingshould exercise extreme careand wear proper safety equip-ment. This should include, butis not limited to chemicalsplash goggles, face shield,NIOSH/MSHA approved acid-gas respirator, acid type rain-suit, rubber gloves and rubberboots. Keep other personnelaway from the area unlessthey are wearing safety equip-ment.

3. The employees responsiblefor chemical unloading shouldbe knowledgeable of theproducts they handle, theirpotential hazards and precau-tions to be taken.

4. A safety shower and eyewash must be readily accessi-ble and should be tested reg-ularly. Visualize an escaperoute for yourself in the eventof an incident and locate theremote shut-off valve.

5. Spill control equipment mustbe available and personnelshould be trained to handleall types of spills. If a spilloccurs:- Protect yourself from injury- Try to stop or minimize thespill-Warn others of the dangerarea-Notify the emergencyresponse personnel for prop-er cleanup-Notify appropriate authorities

6. All U.S. Department ofTransportation (DOT) regula-tions concerning bulk vesselunloading should be fol-lowed. (See 49 CFR Parts172 through 180)

7. No smoking or flames arepermitted in the area due tothe potential generation ofhydrogen under certain situa-tions.

8. Carefully read the bill of lad-ing and check the vesselplacards to assure that theproduct delivered is in factthe product desired.

9. It is important that all deliveryunloading lines be clearlylabeled with the identity of thecorresponding storage tankcontents. In addition, dedicat-ed unloading lines are desir-able to prevent cross contam-ination. Accidental unloadingof another product into themuriatic acid tank could resultin an extremely dangeroussituation.

10. Before unloading, carefullyread the bill of lading todetermine the amount ofproduct in the delivery vessel.Make certain that the storagetank is properly vented andhas sufficient capacity toreceive the entire load beingdelivered. Also make certainthat the level monitoringdevice is functional. Frequentchecks during the unloadingprocedure are recommended.

11. Check all transfer lines andhoses to make sure they aredry and free of contamination.Inspect equipment for signsof deterioration or other con-ditions which might cause aleak. Do not unload if there isany question about the condi-tion of any equipment.

12. No one should enter thedelivery vessel under any cir-cumstances.

13. Spot the delivery vessel on alevel, preferably paved sur-face in a designated unload-ing area. This should be asclose to the designatedreceiving tank (or unloadingpump) as possible. Setbrakes, block or chockwheels, and establish anelectrical ground to provide apoint of discharge for any sta-tic build-up. Flag-off the areaand/or place caution signs atboth ends of the delivery ves-sel being unloaded. In thecase of tank car shipments, aderail attachment may beadvisable on the open end ofthe siding.

14 of 34

sel. Shut off the pump at thistime. If using air pressure, arush of air can be heard inthe discharge line. Continuethe air pressure until theunloading line is blown free ofacid. With the air pressurestill turned on, a block valvemay now be closed on theunloading line near the deliv-ery vessel (see Figure 2).This procedure will minimizethe possibility of liquidremaining in the lines whenthe delivery vessel is discon-nected.

19. Carefully vent the deliveryvessel to zero gauge pres-sure and cautiously discon-nect the air and dischargelines. Be prepared with a suit-able container to collect anyproduct remaining in the line.Have appropriate supplies tocontain or clean up any pos-sible leakage that may occur.

20. Close all valves and replaceall caps and blind flanges onthe delivery vessel. Make cer-tain that the dome cover isfastened securely and electri-cal grounding wires areremoved. Flush hoses withwater and wash down areawhere any vapors or leakagemay have occurred.

21. For the return of muriatic acidtank cars, the person whooriginally installed themshould release hand brakes,remove wheel chocks andwarning signs.

22. Release the empty vesselpromptly in accordance withthe shipper’s instructions.The shipper’s routing direc-tions must be followed in allinstances.

23. If a bulk unit is to be returnedpartially filled, it also must bevented to zero gauge pres-sure. In addition, a phone callmust be placed toOxyChem’s Technical ServiceDepartment before the unit isreturned.

UNLOADING PROBLEMS

Occidental’s Technical ServiceDepartment should be promptlycontacted if there are anyunloading difficulties from ourtank trailers or tank cars. Brokenwell lines, faulty gaskets, leakingmain valves, faulty safety reliefvalves, and blown rupture discscan cause unloading problemsand should be brought to ourattention. Every effort is made onour part to prevent these prob-lems. Each bulk unit is subjectedto a thorough safety inspectionbefore and after loading prior to itleaving our plant.

Unloading & HandlingHydrochloric Acid

14. Make certain that the fumescrubber is functioning prop-erly, then carefully vent thedelivery vessel to slowlyrelease any pressure built upduring transit.

15. Remove the blind flange andcarefully connect the unload-ing line with an appropriategasket.

16. If air pressure is to be used,connect a regulated air linethat will not exceed 25 psig.Use of a pressure gauge atthe air connection is an advis-able safety precaution. Note:The air line should be thor-oughly blown out before it isconnected to assure it is freeof contamination. If a pump isto be used for unloading, thevessel dome should beopened to prevent vacuumcollapse. Note: A smallamount of air pressure maystill be required to prime thepump.

17. Cautiously open the storagetank inlet valve, followed bythe delivery vessel’s unload-ing valve. Slowly apply airpressure (or turn on thepump) until there is a normalflow of acid to the storagetank. All fittings should bethoroughly inspected for leaksor other defects at this time. Ifleaks or other problems arefound, the unloading processshould be discontinued imme-diately until they are correct-ed.

18. Unloading will be completewhen there is a rapid pres-sure drop in the delivery ves-

15 of 34Equipment for HandlingMuriatic Acid

MATERIALS OFCONSTRUCTION

Concentrated muriatic acid willattack most commonly used met-als such as steel, stainless steel,nickel and many nickel alloys.Corrosion resistance can befound among certain metals, rub-bers, ceramics, plastics, impreg-nated carbon and graphite.Nickel has good resistance toHCl gas at very high tempera-tures. However, in muriatic acidservice, it is limited to low con-centrations at ambient or coldtemperatures. Oxidizing agentssuch as ferric and cupric saltsand dissolved air increase corro-sion rates considerably.

Any equipment that will come incontact with muriatic acid or itsfumes should be made of corro-sion resistant material. Thisincludes not only tanks anddikes, but also support servicessuch as ladders, pipe hangersand gratings.

Table 1 contains many of thetypical materials used in industryand their relative resistance tohydrochloric acid.

STORAGE TANKS

Above ground tanks are usuallypreferred since construction andtank maintenance are less costly,gauging and pumping are facili-tated, and should a leak develop,it is easier to detect. Storagefacilities for muriatic acid shouldgenerally be large enough tosupply requirements for at leastone month or have a capacity ofat least 50% over the deliveredvolume. This will provide forreserve supply between ship-ments.

All regulations concerning stor-age tanks should be reviewedbefore installing a bulk storagesystem. Storage tank fabricationshould be of all welded construc-tion. All inside welds should be

ground smooth to avoid punctur-ing the rubber lining. The tankshould be designed with a wallthickness as per ASTM and/orASME recommendations basedon the design, capacity and pres-sure rating (minimum shell thick-ness should be 1/4 inch). If airpressure will be used for acidtransfer, the tanks must meetadditional ASME codes.

In the case of muriatic acid,either horizontal or vertical rubberlined steel tanks are recommend-ed for storage. A horizontal tankis generally easier to repair andmaintain. On the other hand, avertical design is generally pre-ferred since it conserves spaceand the ground support is lessexpensive. Depending on theconditions, it is often practical tomount vertical tanks on tamped,oiled sand pads, supported bycrushed stone, or on a concretepad. The design of a concretepad or saddle foundation shouldbe based on the tank weight plusthe weight of the acid times thetank capacity. Saddles are gener-ally constructed of reinforcedconcrete brick or steel.

New installations should bethoroughly cleaned, water tested,drained and dried before use.The initial filling should bewatched closely for leaks whichmay not have been detected bywater testing. Rubber lined steeltanks should then be inspectedat least every two years insideand out. Liner failure will be evi-dent via a color change in theacid as iron from the tank’s steelis exposed and converted to asoluble salt.

The following procedures willhelp to increase the life of a rub-ber lined tank:

•Wash the tank only whennecessary•Guard against cuts of anysort•Do not alternate from oneservice to another•Install tanks on a firm base

•Use flake graphite if lubricantis needed•Guard against harmfulagents such as oil, grease orsolvent type chemicals•No welding or burning on ornear tank (heat may affect lin-ing)

Fiberglass reinforced plastic(FRP) with an extra thick interiorcorrosion liner is also suitable forstorage of muriatic acid. Due tocertain design constraints, pres-sure is not typically used to trans-fer acid out of FRP tanks. Thesetanks, however, have the advan-tage of having corrosion resis-tance inside and out. FRP tanksshould be inspected externally atleast once a year, and internallyevery five years.

High density cross linked poly-ethylene can also be used forvertical tank construction.Although these tanks cannot takepressure and are generally small,they are corrosion resistant andcan be connected together.Polyethylene tanks should beinspected at least annually.

Equipment for HandlingMuriatic Acid16 of 34

Plug valves should be used forbottom outlet valves on tanks. Asafety plug should be providedfor the bottom outlet to stop leaksfrom the outlet valve or piping.The inlet pipe should enter nearthe top of the tank and extendclose to the tank bottom for sub-merged filling. Submerged fillingwill greatly reduce the formationof mist and the release of hydro-gen chloride gas associated withsplash filling from the top of thetank. This fill pipe should have asmall vacuum breaker hole drilledin the line to prevent a backsiphon from being created.

When installing a tank, it isdesirable to have the bottomsloped slightly (1” in 15’) to allowfor complete drainage. All storagetanks should have flanged man-ways on the top and bottom forentry and cleaning purposes.Tanks should also have at least a4” vent line connected to a scrub-ber for fume control.

DIKES

Primary or secondary contain-ment capable of holding at least110% of the tank contents isdesirable (mandatory in somestates) to prevent any spillagefrom entering surface or groundwater in the event of a tank fail-ure. Dikes lined with a 6” to 8”bed of 2” limestone have beenused. A preferred arrangementincorporates a leak-proof con-crete dike equipped with an acidresistant liner. This arrangementwill not only prevent contamina-tion of the environment, but alsoallow the spilled acid to be recov-ered. All dikes should be dead-ended and isolated from sewers.

PIPING - RIGID

Acid transfer lines should haveas short a run as possible and bemade of 2” (minimum) flangedpiping. They should be well

anchored/braced and sloped forcomplete drainage. Loops andpockets should be avoided.Flanged pipe lends itself to easymaintenance in the event of aleak from a line or in case an in-line valve has to be replaced.Schedule 80 flanged polyvinylchloride (PVC), polyethylene,CPVC, FRP, fluorocarbon or acidresistant rubber lined steel pipe,or armored glass are acceptablematerials of construction. Rubberlined steel is recommended fordischarge piping. Flanged pipingis preferred. However, if threadedpiping is used it should berestricted to line sizes below 2”and the threads should be coatedwith Teflon® tape Transfer linesshould be tagged and/or colorcoded and show flow direction.Installation of a 150 psig rated in-line flanged sight glass madefrom either armored glass, clearPyrex®, transparent rigid acrylicor PVC resin is recommended.This device will indicate tounloading personnel when thetank trailer or car is empty, thusminimizing fumes and the possi-bility of over-taxing the fumescrubber.

All piping should be visuallyinspected for leaks on a dailybasis. All leaks should berepaired as soon as possible.Rigid piping should have a thor-ough annual inspection.

PIPING - FLEXIBLE

When unloading muriatic acid,a 2” flexible hose lined with acidresistant rubber, crosslinked poly-ethylene or a fluorocarbon liningis suggested for use between thedelivery vessel and the stationaryunloading lines. The connectionfor liquid transfer on tank trailersand cars hauling acid is a 2” four-hole flange.

Kamlock or other quick discon-nect fittings for liquid transferincrease the risk of possible leaksand are not recommended.

Flexible piping should beinspected for signs of deteriora-tion every time it is used.Pressure test each hose sectionat least once a year. Do not allowhoses to be stored or used in aposition where the recommendedbend radius is exceeded.

LEVEL CONTROL

Diaphragm sealed pressuretransmitters located near the bot-tom of the storage tank with suit-able valving are recommendedfor level control. Transmitterhousings are available of moldedPVC,polypropylene or fluorocar-bon thermoplastic such asHalar®. The level control assem-bly should be protected with adiaphragm made of Viton®,Teflon, or tantalum. Some FRPtanks are transparent enough tomake visual level measurement.In these cases, a graduated tapeis attached vertically to the exteri-or of the tank showing level.

Standard high level and over-flow alarms are also recommend-ed.

17 of 34Equipment for HandlingMuriatic Acid

They are sealless, self-priming,and rotary in action. They have nostuffing boxes, glands, shaft seals,gasket or check valves which canleak or malfunction. Pumping isbased on a progressive “squeegee”action generated by an oscillating,eccentric shaft. They can run dryfor extended periods without dam-age. Capacities up to 40 GPM anddischarge pressures as high as 45psig can be realized.

All pumps should be visuallyexamined for leaks on a daily basisand inspected more thoroughly ona yearly basis.

Note: Pumps should never bethrottled on the suction side.

VALVES

Most of the common valve typesmay be used for muriatic acid ser-vice, including ball, plug,diaphragm, pinch, clamp and but-terfly valves. They must, however,be made of acid resistant materialssuch as Teflon, Saran, Kynar, FRP,PVC, polypropylene, glass, porce-lain, ceramic or graphite/PPS.Quarter turn PVC flanged ballvalves are widely used for servicewith muriatic acid. The primarystorage tank valves, however, aregenerally heavy duty Teflon plugvalves. This type plug valve is alsoutilized on tank trailers handlingmuriatic acid.

All valves should be visuallyinspected for leaks on a daily basisand a detailed inspection per-formed at least yearly.

GASKETS

The gaskets should be made ofTeflon, Viton fluoroelastomer (up toabout 150°F), EPR (ethylenepropylene rubber - up to about200°F), PTFE or Kynar.

PUMPS

Probably the most seriousproblem with chemical pumps,particularly those in service withstrong corrosive liquids like muri-atic acid, is the environmentaland safety issues created byleakage from the stuffing box ormechanical shaft seal. As aresult, magnetic driven seallesspumps have gained tremendouspopularity with their dependableleak-free service.

Self-priming plastic centrifugaltype pumps with 50% excesshead have also been used exten-sively over the years. They areideal for high flow and low pres-sures. The wetted parts of thepump should be made of PVC,CPVC, polypropylene (PP), TFE,Kynar®, FRP, carbon (Karbate)or ceramic construction. Theideal type of pump for muriaticacid service is one that is self-priming and is totally constructed,wetted and non-wetted parts, ofcorrosion resistant plastics (evento the point where the shaft isencased in a totally inert plastic.)Self-priming centrifugal pumpsare available and designed tohandle flows from 5 to 1,000 gpmand discharge heads to 200 feet.They are engineered for continu-ous or intermittent service.

An alternative pump type suit-able for hydrochloric acid serviceis a diaphragm metering pumpwith diaphragms made of corro-sion resistant materials like Vitonor TFE. Metering, as the nameimplies, can be throttled to controlflow for intermittent or continuoususage.

Although they have limited flowcapacity, peristaltic pumps arealso suitable for pumpinghydrochloric acid and avoid manyof the maintenance problemsgenerally associated with pumps.

FUME SCRUBBER

Bulk storage facilities for muri-atic acid should be serviced witha dedicated scrubber for han-dling fumes during the filling ofthe acid storage tank and blow-down of the tank trailers or cars.Local applicable air pollutioncontrol regulations may prescribethe type of scrubber controldevice design and/or operatingrequirements. Such require-ments must be strictly observed.

The efficiency of any scrubberwill depend upon its design,degree of maintenance and tem-perature of the scrubbing medi-um. Usually an ejector-venturitype scrubber is more economi-cal and easier to maintain thanpacked tower scrubbers. Haveg,FRP, PVC, polypropylene andTFE linings are acceptable mate-rials of construction. An 18-20%aqueous caustic soda solution isgenerally used as the scrubbermedium. It may be advisable toinstall a check valve and/or liquidsensing alarm between the muri-atic acid storage tank and scrub-ber to prevent any reverse flowinto the storage tank. This poten-tial problem is generally due tothe design of the scrubber and/orthe fact that it handles

BYPASS

Although not mandatory whenusing a centrifugal pump, it isrecommended that a bypass linebe provided to ensure that thepump is supplied with adequateflow even when the flow is shutoff at the receiving end of theline. This arrangement preventspump strain (a must when a posi-tive displacement pump is used)and piping damage. A shut-offvalve is generally also located onthe end of the transfer line at theprocess.

GAUGE

Many installations dependentirely on a calibrated dip stickfor gauging. The dip stick methodis an inexpensive, maintenance-free gauge and is sometimesused in addition to the usualinstrumentation. The gaugingmethod to be used and the tankoutlets required must be deter-mined prior to ordering the tank.

PRESSURE-VACUUM RELIEFSYSTEM

Tanks containing muriatic acidshould be equipped with a pres-sure-vacuum relief valve toreduce evaporation losses. Alsocalled a conservation vent, thissystem will help to minimize con-stant venting due to minor pres-sure fluctuations that are wellwithin the pressure rating of thetank. Although normal relief valvesettings of 4 psig pressure and 1ounce vacuum are employed, it isimportant that the relief valve set-tings do not exceed the tank’spressure and vacuum ratings.Refer to the specific parametersfor your tank design.

18 of 34

Equipment for HandlingHydrochloric Acid

other acidic gases such as thosefrom reactor streams. If an 18-20% caustic soda is used, provi-sions should be made to monitorthe strength of the caustic sodausing ORP or titration, and toanticipate possible freezing of thecaustic in winter months.

Water can also serve as ascrubbing medium. A packedtower utilizing water can not onlyachieve a very high degree ofefficiency, but the muriatic acidproduced from the HCl fumes canthen be used elsewhere in thefacility.

A soda ash solution seal canbe used to cut down on acidfumes from storage tanks if ascrubber is not available. Thesoda ash solution is placed underthe vent line to neutralize acidfumes from tank loading or nor-mal warming of the contents dur-ing the day. Make sure the seal isdesigned so that the seal fluidcannot be sucked into the tankwhen acid is removed from thetank. Replace the soda ash sealsolution when it is depleted.

Whichever type is used, thescrubber medium should be mon-itored weekly (more often if usedheavily) to ensure effectiveremoval of the acid fumes. Thescrubber itself should be inspect-ed at least annually. Leaksshould be fixed as soon as possi-ble and any evidence of liner fail-ure addressed immediately.

MANHOLES

Manholes on storage tanks arenecessary for access and ventila-tion during inspection and clean-ing. Two manholes, 24” in diame-ter, are desirable. One manholeshould be located on top of thetank and one on the side near thebase of the tank.

DRAIN LINES

A 2” flanged and valved outletshould be provided at the floorlevel of the tank for completedrainage when necessary. Thisoutlet should be located so that itcan be tied into the pump whenneeded. Since this outlet willrarely be used, it is suggestedthat the valve be equipped with alocking system.

GROUND (ELECTRICAL)

A ground line is an added safe-ty feature, providing a point ofdischarge for any static build-up.More than one rod should beused to minimize the danger ofrods becoming corroded andinoperative. They should be con-nected by means of an under-ground copper wire.

OUTLET LINE

A 2” (minimum) flanged outletline for normal acid withdrawalshould be located 3 to 4 inchesabove the tank floor. This lineshould be tied into the pumpingsystem. A valve should be locat-ed between the tank and thepump. A reducer may be useddownstream of the valve on theoutlet flange, as needed.

19 of 34Equipment for HandlingMuriatic Acid

VENT BREATHER/RUPTUREDISC

Tank venting is critical since thevolume of air in a storage tankchanges almost constantly. It willchange not only with liquid aciddeliveries and withdrawals (work-ing loss), but also with expansionand contraction due to tempera-ture fluctuations (breathing loss).In the event that the Pressure-Vacuum Relief System fails, abackup system should be provid-ed to protect the tank againstbursting under pressure or col-lapsing with vacuum. Tanksshould be equipped with anappropriate pressure releasedevice based on the designedvessel rating. The rupture discassembly (at least 3” diameterand generally made of a compos-ite) and/or pressure release valvein combination with a rupturedisc, can be used. The fumesdischarged from this systemshould be sent to a dedicatedscrubber to prevent their releaseto the environment.

RECOMMENDEDINSPECTION & MAINTENANCE

Storage tanks should be thor-oughly inspected at least annual-ly. At this time, wall thicknessreadings should also be taken toassure there is no corrosion dueto lining failures.

Whenever storage associatedequipment is being used, it is agood practice to visually inspectvalves, pumps, flanges, etc. forleaks. Parts of the storage facilitywhich are most susceptible toloss of integrity should beinspected on a prescheduled

basis. Bolted connections that aresubject to vibration, relaxation, ordeterioration should be checkedfor tightness every six months orless.

TANK ENTRY PRECAUTIONS

Before entering a tank, vesselor other confined space for clean-ing, inspection, etc., carefullyreview the following precautions.Also refer to ANSI Z117.7 foradditional tank and confinedspace entry precautions, andcomply with the OSHA ConfinedSpace Entry Requirements.

• Every effort must be made toremove all acid from the tankand related piping. It must bethoroughly washed with water,drained, ventilated and checkedfor absence of acid vapors.

• Any power driven equipment,such as agitators,that mighteffect the confined space mustbe made inoperable by lockingout and tagging.

• The confined space must beisolated from process and ser-vice systems. All pipes leadingto or from the tank (exceptvents) should be disconnectedor blanked off. Do not rely onvalves. Slip-in blanks must be ofsufficient strength to withholdmaximum applied pressure orvacuum. Open ends of discon-nected lines must be blanked offor capped.

• Remove all manhole covers,clean out covers, etc. Escaperoutes from the confined spacemust be clear of obstructions.

• Forced ventilation should beapplied as long as someone isin the tank.

• As a minimum, an explosionmeter and oxygen test mustindicate that the atmosphere issafe to enter. A toxicity testshould indicate that the atmos-phere is below the PEL. If workwith in the confined space isinterrupted, atmospheric tests ofthe confined space must betaken again prior to reentry.

• All pumps and other mechanicalequipment must be locked inthe “off” position and identifiedwith safety tags.

• Anyone entering a tank mustwear proper personal protectiveequipment, including but notlimited to air supplied respirator,life line and body harness orwristlets. A set of the sameequipment must be on the siteand ready for use by the safetymonitor.

• A person designated as safetymonitor shall be posted at theaccess opening before anyoneenters the confined space. Thisperson must be properlyinstructed, equipped and pre-sent at all times outside thetank

• Before entering a tank car ortank trailer, the wheels must bechocked, brakes set and areaflagged off.

Technical Data20 of 34

Table 1

Corrosion Resistance to HClMaterial 1-20% HCl >20% HCl >20% HCl @ 175°F

MetalsAluminum NR NR NRCarbon-Graphite, Resin Impregnated A<480°F A<480°F A<480°FCarbon Steel NR NR NRCopper Nickel, 90/10 or 70/30 NR NR 37% NRHastelloy B A A 100% B 100%Hastelloy C A A C 10%Inconnel NR NR 20% NR <30%Monel NR NR NRNickel AB C-NR NRStainless Steel, 303, 304 & 316 NR NR NRTantalum A A to 300°F ATitanium BC 20% C/NR 37% NRZirconium A to 212°F A 37% to 212°F A

Non-MetalsAcid Proof brick - Carbon - A 37% to 930°F -Acid Proof brick - Fireclay - A 37% to 2500°F -Epoxy A to 70°F,BC@122°F A 37% at 70°F NR

- AB 50% to 150°FGlass - A 37% to 450°F -Glass reinforced epoxy or polyester - A 37% to 220°F -Graphite - A 37% to 750°F -Halar, E-CTFE A A to 100% AKEL-F A 70°F A 100% to 300°F AKynar A to 275°F A 100% to 275°F A to 275°FNeoprene - A 37% to 220°F -Noryl A A 37% A 37%Nylon A 10% at 70°F NR>10% at 70°F NR

C 10% at 100°F - -Polycarbonate A A 20%, NR 37% @70°F A 20%Polyethylene, UHMW A at 70°F A to 120°F APolyethylene, HMW A 20% to 150°F AB 40% to 150°F -Polypropylene AC to 175°F NR 35% to 140°F AC to 40%Polysulfone A A 37% A 37%Polyvinyl Chloride (PVC) A to 140°F AB to 140°F NRRubber-Lined Carbon Steel A to 150°F A 37% to 150°F -Ryton A A 37% ATeflon, TFE A A 100% to 260°F ATeflon, FEP A 70°F A to 200°F ATeflon, PFA A to 248°F A to 36% to 248°F ATefzel, ETFE A 70°F A at 223°F A

A = Little to no attack C = Limited ResistanceB = Good Resistance NR = Not Recommended

Note : this data is generalized and any specific materials should be tested prior to design and use. All temperatures are assumed to be at 70°F for metals and 200°F for non-metals unless otherwise indicated. Concentrations are listed as an upper limitation for that rating.

Technical Data 21 of 34

Strengths

20° Bé 22° Bé 23 Bé

HCl, wt % 31.45 35.21 37.14

Specific Gravity (60/60°F) 1.1600 1.1789 1.1885

Pounds per Gallon (@ 20°C/68°F) 9.67 9.83 9.91

Pounds of HCl per Gal. of Solution (@20°C/4°C) 3.10 3.54 3.77

Boiling Point, °C (Approximate)* 80 60 51

°F (Approximate) * 176 140 124

Freezing Point, °C (Approximate) -45 -34 -28

°F (Approximate) -49 -29 -18

Specific Heat, Btu/lb/°F (@20°C/68°F) 0.61 0.58 0.57

Heat Evolved on Infinite Dilution of HCl SolutionsKCal/Mole HCl (@25°C/77°F) 3.0 3.9 4.1

Surface Tension of HCl Sol, Dynes/cm (@20°C/68°F) 69.2 67.8 67.4

Partial Pressure of HCl gas over Muriatic Acid (20°C) mm Hg 19 80 150

Partial Pressure of Water over Muriatic Acid (20°C) mm Hg 4.8 3.4 2.7

Vapor Density @20°C (Air=1) 1.3 - -

Appearance Clear to slightly yellow liquid

Odor Sharp irritating odor

Flash Point ** None

Autoignition Temperature ** None

Flammability Limits in Air ** Non-Flammable

* All aqueous solutions of acid, on boiling, approach a constant boiling mixture which contains 20.24% HCl (approximately 13.4° Bé, Sp. Gr. 1.1016) and boils at 110°C/230°F.

** Muriatic Acid is non-flammable and non-explosive under normal conditions of use. However, reaction of this product with metals will produce hydrogen gas which is extremely flammable and explosive under certain conditions. Smoking should not be allowed in areas where muriatic acid is handled.

Normality of acid solution 0.5N 1.0N 2.0N 4.0NRefractive index, nD

18 (@ 18°C) 1.33753 1.34168 1.34977 1.36480

Table 2Physical Properties of Muriatic Acid

(CAS Number 7647-01-0)

Technical Data22 of 34

°Bé Sp. Gr. %HCI °Tw °Bé Sp.Gr. %HCI °Tw °Bé Sp. Gr. %HCI °Tw1.00 1.0069 1.40 1.38 16.0 1.1240 24.57 24.80 20.8 1.1675 32.93 33.502.00 1.0140 2.82 2.80 16.1 1.1248 24.73 24.96 20.9 1.1684 33.12 33.683.00 1.0211 4.25 4.22 16.2 1.1256 24.90 25.12 21.0 1.1694 33.31 33.884.00 1.0284 5.69 5.68 16.3 1.1265 25.06 25.30 21.1 1.1703 33.50 34.06

5.00 1.0357 7.15 7.14 16.4 1.1274 25.23 25.48 21.2 1.1713 33.69 34.265.25 1.0375 7.52 7.50 16.5 1.1283 25.39 25.66 21.3 1.1722 33.88 34.445.50 1.0394 7.89 7.88 16.6 1.1292 25.56 25.84 21.4 1.1732 34.07 34.645.75 1.0413 8.26 8.26 16.7 1.1301 25.72 26.02 21.5 1.1741 34.26 34.82

6.00 1.0432 8.64 8.64 16.8 1.1310 25.89 26.20 21.6 1.1751 34.45 35.026.25 1.0450 9.02 9.00 16.9 1.1319 26.05 26.38 21.7 1.1760 34.64 35.206.50 1.0469 9.40 9.38 17.0 1.1328 26.22 26.56 21.8 1.1770 34.83 35.406.75 1.0488 9.78 9.76 17.1 1.1336 26.39 26.72 21.9 1.1779 35.02 35.58

7.00 1.0507 10.17 10.14 17.2 1.1345 26.56 26.90 22.0 1.1789 35.21 35.787.25 1.0526 10.55 10.52 17.3 1.1354 26.73 27.08 22.1 1.1798 35.40 35.967.50 1.0545 10.94 10.90 17.4 1.1363 26.90 27.26 22.2 1.1808 35.59 36.167.75 1.0564 11.32 11.28 17.5 1.1372 27.07 27.44 22.3 1.1817 35.78 36.34

8.00 1.0584 11.71 11.68 17.6 1.1381 27.24 27.62 22.4 1.1827 35.97 36.548.25 1.0603 12.09 12.06 17.7 1.1390 27.41 27.80 22.5 1.1836 36.16 36.728.50 1.0623 12.48 12.46 17.8 1.1399 27.58 27.98 22.6 1.1846 36.35 36.928.75 1.0642 12.87 12.84 17.9 1.1408 27.75 28.16 22.7 1.1856 36.54 37.12

9.00 1.0662 13.26 13.24 18.0 1.1417 27.92 28.34 22.8 1.1866 36.73 37.329.25 1.0681 13.65 13.62 18.1 1.1426 28.09 28.52 22.9 1.1875 36.93 37.509.50 1.0701 14.04 14.02 18.2 1.1435 28.26 28.70 23.0 1.1885 37.14 37.709.75 1.0721 14.43 14.42 18.3 1.1444 28.44 28.88 23.1 1.1895 37.36 37.90

10.00 1.0741 14.83 14.82 18.4 1.1453 28.61 29.06 23.2 1.1904 37.58 38.0810.25 1.0761 15.22 15.22 18.5 1.1462 28.78 29.24 23.3 1.1914 37.80 38.2810.50 1.0781 15.62 15.62 18.6 1.1471 28.95 29.42 23.4 1.1924 38.03 38.4810.75 1.0801 16.01 16.02 18.7 1.1480 29.13 29.60 23.5 1.1934 38.26 38.68

11.00 1.0821 16.41 16.42 18.8 1.1489 29.30 29.78 23.6 1.1944 38.49 38.8811.25 1.0841 16.81 16.82 18.9 1.1498 29.48 29.96 23.7 1.1953 38.72 39.0611.50 1.0861 17.21 17.22 19.0 1.1508 29.65 30.16 23.8 1.1963 38.95 39.2611.75 1.0881 17.61 17.62 19.1 1.1517 29.83 30.34 23.9 1.1973 39.18 39.46

12.00 1.0902 18.01 18.04 19.2 1.1526 30.00 30.52 24.0 1.1983 39.41 39.6612.25 1.0922 18.41 18.44 19.3 1.1535 30.18 30.70 24.1 1.1993 39.64 39.8612.50 1.0943 18.82 18.86 19.4 1.1544 30.35 30.88 24.2 1.2003 39.86 40.0612.75 1.0964 19.22 19.28 19.5 1.1554 30.53 31.08 24.3 1.2013 40.09 40.26

13.00 1.0985 19.63 19.70 19.6 1.1563 30.71 31.26 24.4 1.2023 40.32 40.4613.25 1.1006 20.04 20.12 19.7 1.1572 30.90 31.44 24.5 1.2033 40.55 40.6613.50 1.1027 20.45 20.54 19.8 1.1581 31.08 31.62 24.6 1.2043 40.78 40.8613.75 1.1048 20.86 20.96 19.9 1.1590 31.27 31.80 24.7 1.2053 41.01 41.06

14.00 1.1069 21.27 21.38 20.0 1.1600 31.45 32.00 24.8 1.2063 41.24 41.2614.25 1.1090 21.68 21.80 20.1 1.1609 31.64 32.18 24.9 1.2073 41.48 41.4614.50 1.1111 22.09 22.22 20.2 1.1619 31.82 32.38 25.0 1.2083 41.72 41.6614.75 1.1132 22.50 22.64 20.3 1.1628 32.01 32.56 25.1 1.2093 41.99 41.86

15.00 1.1154 22.92 23.08 20.4 1.1637 32.19 32.74 25.2 1.2103 42.30 42.0615.25 1.1176 23.33 23.52 20.5 1.1647 32.38 32.94 25.3 1.2114 42.64 42.2815.50 1.1197 23.75 23.94 20.6 1.1656 32.56 33.12 25.4 1.2124 43.01 42.4815.75 1.1219 24.16 24.38 20.7 1.1666 32.75 33.32 25.5 1.2134 43.40 42.68

Allowance for T emperature 10-15° Bé 15-22° Bé 22-25° BéSp. Gr. Correction Factor, per °F 0.0002 0.0003 0.00035

Table 3Specific Gravities of Muriatic Acid Solutions

(60°F / 60°F)

23 of 34Technical Data

SPECIFIC GRAVITY DETERMINATION

Specific gravity determinations in Table 3 were made at 60°F, compared with water also at 60°F. From the specificgravities, the corresponding degrees baumé were calculated by the following formulas:

1. Sp. Gr. = 145 / (145 - °Bé)2. Degrees Baume = 145 - (145 / Sp. Gr.)

Similarly, degrees Twaddell may be calculated from specific gravity:

3. Sp. Gr. = [(0.5 X °Tw) + 100] / 1004. Degrees Twaddell = 200 (Sp. Gr. - 1)

The values may be determined by means of a glass hydrometer at room temperature and corrected to the desiredtemperature or to the standard temperature of 15.5°C/60°F. After it is graduated by Formula #1, it should be print-ed on the scale.

24 of 34 Technical DataTable 4

Temperature Correction for Hydrometer Readings(°Bé Aqueous HCl Solutions Corrected to 60°F)

°Bé @ 40°F 50°F 60°F 70°F 80°F 90°F 100°F 110°F 120°F 130°F18.5 17.83 18.17 18.50 18.83 19.17 19.50 19.83 20.17 20.50 20.8318.6 17.93 18.27 18.60 18.93 19.27 19.60 19.93 20.27 20.60 20.9318.7 18.03 18.37 18.70 19.03 19.37 19.70 20.03 20.37 20.70 21.0318.8 18.13 18.47 18.80 19.13 19.47 19.80 20.13 20.47 20.80 21.1318.9 18.23 18.57 18.90 19.23 19.57 19.90 20.23 20.57 20.90 21.2319.0 18.33 18.67 19.00 19.33 19.67 20.00 20.33 20.67 21.00 21.33

19.1 18.43 18.77 19.10 19.43 19.77 20.10 20.43 20.77 21.10 21.4319.2 18.53 18.87 19.20 19.53 19.87 20.20 20.53 20.87 21.20 21.5319.3 18.63 18.97 19.30 19.63 19.97 20.30 20.63 20.97 21.30 21.6319.4 18.73 19.07 19.40 19.73 20.07 20.40 20.73 21.07 21.40 21.7319.5 18.83 19.17 19.50 19.83 20.17 20.50 20.83 21.17 21.50 21.83

19.6 18.93 19.27 19.60 19.93 20.27 20.60 20.93 21.27 21.60 21.9319.7 19.03 19.37 19.70 20.03 20.37 20.70 21.03 21.37 21.70 22.0319.8 19.13 19.47 19.80 20.13 20.47 20.80 21.13 21.47 21.80 22.1319.9 19.23 19.57 19.90 20.23 20.57 20.90 21.23 21.57 21.90 22.2320.0 19.33 19.67 20.00 20.33 20.67 21.00 21.33 21.67 22.00 22.33

20.1 19.43 19.77 20.10 20.43 20.77 21.10 21.43 21.77 22.10 22.4320.2 19.53 19.87 20.20 20.53 20.87 21.20 21.53 21.87 22.20 22.5320.3 19.63 19.97 20.30 20.63 20.97 21.30 21.63 21.97 22.30 22.6320.4 19.73 20.07 20.40 20.73 21.07 21.40 21.73 22.07 22.40 22.7320.5 19.83 20.17 20.50 20.83 21.17 21.50 21.83 22.17 22.50 22.83

20.6 19.93 20.27 20.60 20.93 21.27 21.60 21.93 22.27 22.6020.7 20.03 20.37 20.70 21.03 21.37 21.70 22.03 22.37 22.7020.8 20.13 20.47 20.80 21.13 21.47 21.80 22.13 22.47 22.8020.9 20.23 20.57 20.90 21.23 21.57 21.90 22.23 22.57 22.9021.0 20.33 20.67 21.00 21.33 21.67 22.00 22.33 22.67 23.00

21.1 20.43 20.77 21.10 21.43 21.77 22.10 22.43 22.77 23.1021.2 20.53 20.87 21.20 21.53 21.87 22.20 22.53 22.87 23.2021.3 20.63 20.97 21.30 21.63 21.97 22.30 22.63 22.9721.4 20.73 21.07 21.40 21.73 22.07 22.40 22.73 23.0721.5 20.83 21.17 21.50 21.83 22.17 22.50 22.83 23.17

21.6 20.93 21.27 21.60 21.93 22.27 22.60 22.93 23.2721.7 21.03 21.37 21.70 22.03 22.37 22.70 23.03 23.3721.8 21.13 21.47 21.80 22.13 22.47 22.80 23.13 23.4721.9 21.23 21.57 21.90 22.23 22.57 22.90 23.23 23.5722.0 21.29 21.64 22.00 22.36 22.71 23.07 23.43

22.1 21.39 21.74 22.10 22.46 22.81 23.17 23.5322.2 21.49 21.84 22.20 22.56 22.91 23.27 23.6322.3 21.59 21.94 22.30 22.66 23.01 23.37 23.7322.4 21.69 22.04 22.40 22.76 23.11 23.47 23.8322.5 21.79 22.14 22.50 22.86 23.21 23.57

22.6 21.89 22.24 22.60 22.96 23.31 23.6722.7 21.99 22.34 22.70 23.06 23.41 23.7722.8 22.09 22.44 22.80 23.16 23.51 23.8722.9 22.19 22.54 22.90 23.26 23.61 23.9723.0 22.29 22.64 23.00 23.36 23.71 24.07

23.1 22.39 22.74 23.10 23.46 23.81 24.1723.2 22.49 22.84 23.20 23.56 23.91 24.2723.3 22.59 22.94 23.30 23.66 24.0123.4 22.69 23.04 23.40 23.76 24.1123.5 22.79 23.14 23.50 23.86 24.21

Example: A sample of acid is takenfrom the process at 80°F and has ahydrometer reading of 19.4 °Be. Thecorrected reading is 20.07 °Bé at 60°F.

25 of 34Technical Data

Table 5

Specific Gravity of Aqueous Muriatic Acid Solutions(20°C/4°C)

Weight of HCl in solution expressed in

Specific Grams Lb. per Lb. perGravity °Baumé °Twaddell per Liter U.S. Gallon Cu. Foot N %HCl

1.0032 0.5 0.64 10.03 0.08372 0.6263 0.275 1

1.0082 1.2 1.64 20.16 0.1683 1.259 0.553 2

1.0181 2.6 3.62 40.72 0.3399 2.542 1.12 4

1.0279 3.9 5.58 61.67 0.5147 3.850 1.69 6

1.0376 5.3 7.52 83.01 0.6927 5.182 2.28 8

1.0474 6.6 9.48 104.7 0.8741 6.539 2.87 10

1.0574 7.9 11.48 126.9 1.059 7.922 3.48 12

1.0675 9.2 13.50 149.5 1.247 9.330 4.10 14

1.0776 10.4 15.52 172.4 1.439 10.76 4.73 16

1.0878 11.7 17.56 195.8 1.634 12.22 5.37 18

1.0980 12.9 19.60 219.6 1.833 13.71 6.02 20

1.1083 14.2 21.66 243.8 2.035 15.22 6.69 22

1.1187 15.4 23.74 268.5 2.241 16.76 7.36 24

1.1290 16.6 25.80 293.5 2.450 18.33 8.05 26

1.1392 17.7 27.84 319.0 2.662 19.91 8.75 28

1.1492 18.8 29.84 344.8 2.877 21.53 9.5 30

1.1593 19.9 31.86 371.0 3.096 23.16 10.2 32

1.1691 21.0 33.82 397.5 3.317 24.82 10.9 34

1.1789 22.0 35.78 424.4 3.542 26.50 11.6 36

1.1885 23.0 37.70 451.6 3.769 28.20 12.4 38

1.1980 24.0 39.60 479.2 3.999 29.92 13.1 40

Technical Data26 of 34

Partial Pressure of HCl Gas over Muriatic Acid(mm Hg, °C)

%HCl A B 0° 5° 10° 15° 20° 25° 30° 35° 40° 45° 50° 60° 70° 80° 90° 100° 110°

2 11.8037 4736 0.0000117 0.000023 0.000044 0.000084 0.000151 0.000275 0.00047 0.00083 0.00140 0.00380 0.0100 0.0245 0.058 0.132 0.280

4 11.6400 4471 0.000018 0.000036 0.000069 0.000131 0.00024 0.00044 0.00077 0.00134 0.0023 0.00385 0.0064 0.0165 0.0405 0.095 0.21 0.46 0.93

6 11.2144 4202 0.000066 0.000125 0.000234 0.000425 0.00076 0.00131 0.00225 0.0038 0.0062 0.0102 0.0163 0.040 0.094 0.206 0.44 0.92 1.78

8 11.0406 4042 0.000118 0.000323 0.000583 0.00104 0.00178 0.0031 0.00515 0.0085 0.0136 0.022 0.0344 0.081 0.183 0.39 0.82 1.64 3.10

10 10.9311 3908 0.00042 0.00075 0.00134 0.00232 0.00395 0.0067 0.0111 0.0178 0.0282 0.045 0.069 0.157 0.35 0.73 1.48 2.9 5.4

12 10.7900 3765 0.00099 0.00175 0.00305 0.0052 0.0088 0.0145 0.0234 0.037 0.058 0.091 0.136 0.305 0.66 1.34 2.65 5.1 9.3

14 10.6954 3636 0.0024 0.00415 0.0071 0.0118 0.0196 0.0316 0.050 0.078 0.121 0.185 0.275 0.60 1.25 2.50 4.8 9.0 16.0

16 10.6261 3516 0.0056 0.0095 0.016 0.0265 0.0428 0.0685 0.106 0.163 0.247 0.375 0.55 1.17 2.40 4.66 8.8 16.1 28

18 10.4957 3376 0.0135 0.0225 0.037 0.060 0.095 0.148 0.228 0.345 0.515 0.77 1.11 2.3 4.55 8.6 15.7 28 48

20 10.3833 3245 0.0316 0.052 0.084 0.132 0.205 0.32 0.48 0.72 1.06 1.55 2.21 4.4 8.5 15.6 28.1 49 83

22 10.3172 3125 0.0734 0.119 0.187 0.294 0.45 0.68 1.02 1.50 2.18 3.14 4.42 8.6 16.3 29.3 52 90 146

24 10.2185 2995 0.175 0.277 0.43 0.66 1.00 1.49 2.17 3.14 4.5 6.4 8.9 16.9 31.0 54.5 94 157 253

26 10.1303 2870 0.41 0.64 0.98 1.47 2.17 3.20 4.56 6.50 9.2 12.7 17.5 32.5 58.5 100 169 276 436

28 10.0115 2732 1.0 1.52 2.27 3.36 4.90 7.05 9.90 13.8 19.1 26.4 35.7 64 112 188 309 493 760

30 9.8763 2593 2.4 3.57 5.23 7.60 10.6 15.1 21.0 28.6 39.4 53 71 124 208 340 542 845

32 9.7523 2457 5.7 8.3 11.8 16.8 23.5 32.5 44.5 60 81 107 141 238 390 623 970

34 9.6061 2316 13.1 18.8 26.4 36.8 50.5 68.5 92 122 161 211 273 450 720

36 9.5262 2229 29.0 41.0 56.4 78 105.5 142 188 246 322 416 535 860

38 9.4670 2094 63.0 87.0 117 158 210 277 360 465 598 758 955

40 9.2156 1939 130 176 233 307 399 515 627 830

42 8.9925 1800 253 332 430 560 709 900

44 8.8621 1681 510 655 840

46 940

log 10 ppm = A- (B+T), which agrees only approximately with the table. The table is more nearly correct.

Table 6Table 6

Technical Data 27 of 34

Partial Pressure of W ater over Muriatic Acid(mm Hg, °C)

%HCl A B 0° 5° 10° 15° 20° 25° 30° 35° 40° 45° 50° 60° 70° 80° 90° 100°110°6 8.99156 2282 4.18 6.04 8.45 11.7 15.9 21.8 29.1 39.4 50.6 66.2 86.0 139 220 333 492 715

10 8.99864 2295 3.84 5.52 7.70 10.7 14.6 20.0 26.8 35.5 47.0 61.5 80.0 130 204 310 463 677 960

14 8.97075 2300 3.39 4.91 6.95 9.65 13.1 18.0 24.1 31.9 42.1 55.3 72.0 116 185 273 425 625 892

18 8.98014 2323 2.87 4.21 5.92 8.26 11.3 15.4 20.6 27.5 36.4 47.9 62.5 102 162 248 374 550 783

20 8.97877 2334 2.62 3.83 5.40 7.50 10.3 14.1 19.0 25.1 33.3 43.6 57.0 93.5 150 230 345 510 729

22 9.02708 2363 2.33 3.40 4.82 6.75 9.30 12.6 17.1 22.8 30.2 39.8 52.0 85.6 138 211 317 467 670

24 8.96022 2356 2.05 3.04 4.31 6.03 8.30 11.4 15.4 20.4 27.1 35.7 46.7 77.0 124 194 290 426 611

26 9.01511 2390 1.76 2.60 3.71 5.21 7.21 9.95 13.5 18.0 24.0 31.7 41.5 69.0 112 173 261 387 555

28 8.97611 2395 1.50 2.24 3.21 4.54 6.32 8.75 11.8 15.8 21.1 27.9 36.5 60.7 99.0 154 234 349 499

30 9.00117 2422 1.26 1.90 2.73 3.88 5.41 7.52 10.2 13.7 18.4 24.3 32.0 53.5 87.5 136 207 310 444

32 9.03317 2453 1.04 1.57 2.27 3.25 4.55 6.37 8.70 11.7 15.7 21.0 27.7 46.5 76.5 120 184 275 396

34 9.07143 2487 0.85 1.29 1.87 2.70 3.81 5.35 7.32 9.95 13.5 18.1 24.0 40.5 66.5 104 161 243 355

36 9.11815 2526 0.68 1.03 1.50 2.19 3.10 4.41 6.08 8.33 11.4 15.4 20.4 34.8 57.0 90.0 140 212 311

38 9.20783 2579 0.53 0.81 1.20 1.75 2.51 3.60 5.03 6.92 9.52 13.0 17.4 29.6 49.1 77.5 120 182 266

40 9.33923 2647 0.41 0.63 0.94 1.37 2.00 2.88 4.09 5.68 7.85 10.7 14.5 25.0 42.1 67.3 105 158 230

42 9.44953 2709 0.31 0.48 0.72 1.06 1.56 2.30 3.28 4.60 6.45 8.9 12.1 21.2 35.8 57.2 89 135 195

log10 ppm = A - (B+T), which agrees only approximately with the table. The table is more nearly correct.

Table 7

Technical Data28 of 34

Graph 1

Normality vs Wt. % HCl Solutions

0

2

4

6

8

10

12

14

0 5 10 15 20 25 30 35 40

Percent by weight HCl

Nor

mal

ity

Graph 2

Freezing Points of HCl Solutions

Percent by weight HCl

Technical Data 29 of 34

30 of 34 Technical Data

Graph 3Specific Heats of HCl Solutions

(Btu/lb./°F)

Technical Data 31 of 34

Graph 4

Heat Evolved on Infinite Dilution of Muriatic AcidWhen diluting acid on a continual basis, a mixing tee may be used. The heat of dilution should be accounted for inthe design and a few general rules followed. The water stream should flow through the straight run and acid addedvia the side inlet, a check valve should be installed on both feed lines to prevent any possible backflow, materials ofconstruction should be designed to handle the exothermic temperature rise and concentration of the dilute acid.

Example :Determine the heat evolved when 100 pounds of 30% is diluted with water to 8% muriatic acid.From the graph 30% = 148 BTU/#

8% = 39.5 BTU/#The difference is 108.5 BTU/#Pounds of HCl = 100# x 30% = 30#30# x 108.5BTU/# = 3,225 BTU

5

10

100

500

0.1 1 10 100

Percent by weight HCl

BT

U/#

32 of 34 Dilution Calculations

Strong muriatic acid can be used to make weakersolutions by mixing with water. Always add acid towater to avoid excess heat generation.

For a desired number of gallons of a certainstrength acid, use the following formulas to determinethe number of gallons of strong acid to be mixed witheither water or weak acid.

Sg = Strong Acid (gallons)

Sw = Strong Acid weight (pounds)

Sp = Wt. Percent Strength of Strong Acid

Sd = Specific Gravity Strong Acid

Dg = Dilute Acid made from mixing

(total gallons)Dp = Wt. Percent Strength of

Dilute AcidDd = Specific Gravity Dilute Acid

Wg = Water (gallons)

Ww = Water weight (pounds)

Formula #1Sg = D x [(GD x D%) / (GS X S%)]

Formula #2Wg = D x GD x [1 - (D%/S%)]

Formula #3Wg = S x GS x [(S%/D%) - 1]

Note: Before using the above formulas, determinethe specific gravity of the stock strong acid or use avalue from Table 3 that has been corrected to theobserved temperature.

In Formula #1, if you plug in the numbers of gal-lons of Dilute Acid (D) that you want to produce andthen the specific gravities (G) and percent concentra-tions (%) of both the Dilute Acid desired and StrongAcid being used, you can calculate the total number ofgallons of Strong Acid (S) needed.

Formula #2 allows you to calculate the number ofgallons of Water (W) needed to combine with theStrong Acid (S) calculated above, to produce thedesired amount of Dilute Acid (D).

Formula #3 allows you to calculate the number ofgallons of Water (W) needed to combine with a givenamount of Strong Acid (S), to produce the desiredconcentration of Dilute Acid (D).

Example #1:Determine the amount of 22° Bé acid (at 60°F)

and water needed to produce 10 gallons of 18°Béacid.

Sg = Gallons of Strong Acid needed

Sp = 35.21% (22° Bé, see Table 3)

Sd = 1.1789 (Specific Gravity 22° Bé,

see Table 3)Dg = 10 gallons of Dilute Acid

desired to be madeDp = 27.92% (18° Bé, see Table 3)

Dd = 1.1417 (Specific Gravity 18° Bé,

see Table 3)Wg = Gallons of Water needed

Formula #1Sg = 10 x [(1.1417 X 27.92%)/

(1.1789 x 35.21%)]Sg = 10 x [0.31876 / 0.41509]

Sg = 7.68 gallons of 22° Bé acid

@ 60°ForSw = 7.68 gal. x (8.34 lb/gal. x 1.1789

Sp. Gr.)Sw = 75.5 lb. of 22° Bé acid

Formula #2Wg = 10 x 1.1417 x [1 - (27.92% / 35.21%)]

Wg = 11.417 x [0.20704]

Wg = 2.36 gallons of W ater @ 60°F

orWw = 2.36 gal. x 8.34 lb/gal.

Ww= 19.7 lb. of W ater

You may notice when using the dilution calcula-tions above that the sum of the resulting volume ofStrong Acid plus Water to be mixed did not add up tothe 10 gal. volume of Dilute Acid produced. This isbecause there will be shrinkage upon mixing, so thefinal volume will be the desired 10 gal.S + W = D7.68 + 2.36 = 10.04 gal.

Example #2:Determine the number of gallons of water needed

to dilute 1,000 gallons of strong muriatic acid held instorage, to produce a 10% acid solution. The hydrom-eter reading of the acid in storage shows 21.7° Bé at40°F.

First you must convert to 60°F. Look at Table 4 tofind that 21.7° Bé HCI @40°F = 21.03° Bé @ 60°F.Then in Table 3, you will find that 21.0° Bé HCI has aSpecific Gravity = 1.1694 @ 60°F = 33.31%

Sg = 1,000 Gallons of Strong Acid

Sp = 33.31%

Sd = 1.1694

Dp = 10%

Dd = 1.0498 (Specific Gravity 10%,

extrapolated from Table 3)Wg = Gallons of Water needed

Formula #3W = 1,000 x 1.1694 X [(33.31% / 10%)-1] W = 1,169.4 X [2.331]W = 2,726 gallons (22,734 lb.) of Water

Note: Always add acid to water - Not the reverse!

Rectangle Method for DilutionAnother simple way of determining the dilution ratio

for muriatic acid is by the Rectangle Method. It is aquick and accurate way of determining the weights ofacid and water needed to dilute any given strength toany desired strength.

To use this method, merely draw two diagonal inter-secting lines as pictured below. The Sp (Wt. Percentof the Strong Acid) is written in the upper left-handcorner. The strength of the diluent W% (this would bezero when diluting with water) is written in the lowerleft-hand corner. The D% (Wt. Percent of the DiluteAcid) of the desired mixture is written at the diagonal

intersection.

On each diagonal, the smaller percentage is sub-tracted from the larger and the difference is written at

Dilution Calculations 33 of 34

the right-hand end of the same diagonal. The two right-hand figures now give the proportion by weight of eachconstituent; Sw = lb. of strong acid to add, and Ww = lb.of diluent (usually water) to be added.

Example #3:(To show how this method works, we will repeat

Example #1)Determine the amount of 22°Bé acid (at 60°F) andwater needed to produce 10 gallons of 18°Bé acid.

Sw = Pounds of Strong Acid neededSp = 35.21% (22° Bé, see Table 3)Sd = 1.1789 (Specific Gravity 22° Bé,

see Table 3)Dg = 10 gallons of Dilute Acid

desired to be madeDw = Pounds of Dilute Acid to be madeD% = 27.92% (18° Bé, see Table 3)Dd = 1.1417 (Specific Gravity 18° Bé,

see Table 3)Ww = Pounds of Water neededW% = Wt. Percent Diluent

(which = 0 for Water)

Sw = 27.92 - 0 = 27.92 lb.Ww = 35.21 - 27.92 = 7.29 lb.Total = 35.21 lb.Therefore, 27.92 lb. of 22° Bé muriatic acid and 7.29

lb. of water are required to make 35.21 lb. of 18° Béacid. Because we want to make 10 gallons of 18° Bé,the units must be converted and then the ratio of Sw:Wpapplied.

10 gal. 18° Bé = 10 gal. x (1.1417 x 8.34 lb./gal.) =95.2 lb. 18° Bé

Dilution ratio = [Sw/(Sw + Wp)] = Wt. Percent S’

Sw(10gal) = (27.92/35.21) x (95.2 lb. 18° Bé desired)= 75.5 lb. 22° Bé

Ww(10gal) = (7.29/35.21) x (95.2 lb. 18° Bédesired) = 19.7 lb. water

D%

Sp Sw

WwW%

35.21% 27.92

7.290%

27.92%

34 of 34 Methods of Analysis

The following is a summaryof the Methods of Analysis usedto determine muriatic acid quality.A complete copy of these meth-ods is available from theOxyChem Technical ServiceDepartment.

DETERMINATION OF BAUMÉGRAVITY (AND ASSAY)

The Baumé Gravity is deter-mined by means of a glasshydrometer at room temperatureand then corrected to a standardtemperature of 15.5°C/15.5°C.The hydrometer should be stan-dardized to this temperature andcalibrated from 15° to 25° Bé with0.1° Bé increments.

DETERMINATION OF COLOR

Color is determined by acomparison of the sample withAPHA color standards. Themethod used is a modification ofASTM D-1209 and is intendedfor visual color measurement ofessentially water-white liquids.

DETERMINATION OF IRON

Iron is determined colorimetrically with o-Phenanthroline, and an appropriate spectrophotometer.

DETERMINATION OF DIS-SOLVED CHLORINE

Dissolved chlorine is deter-mined by potentiometrically titrat-ing with 0.005N ferrous ammoni-um sulfate. This method is applic-able from 20° to 25° Bé muriaticacid.

DETERMINATION OFEXTRACTABLE ORGANICS

This method allows thedetermination of trace amounts ofextractable organics in aqueousbased samples. Any organics arefirst removed from the sample viahexane microextraction. They arethen analyzed by wide-bore capil-lary column gas chromatography.

® Teflon is a registered trademark of DuPont.

® Pyrex is a registered trademark of Corning.

® Halar is a registered trademark of Ausimont USA Inc.

® Viton is a registered trademark of DuPont.

® Kynar is a registered trademark of Elf Atochem North America.