Hydrochloric acid handling

AH Department of Transportation (DOT), Environmental Protection Agency (EPA), and Occupational Safety and Health Act (OSHA) rules and regulations should be reviewed prior to handling hydrochloric acid and all the regulations must be followed. AH employees handling HCl must be trained to ensure that they are familiar with the appropriate materials safety data sheets and appHcable regulations. 

Neutralization Acidic or basic wastewaters must be neutrahzed prior to discharge. If an industry produces both acidic and basic wastes, these wastes may be mixed together at the proper rates to obtain neutral pH levels. Equahzation basins can be used as neutralization basins. When separate chemical neutralization is required, sodium hydroxide is the easiest base material to handle in a hquid form and can be used at various concentrations for in-line neutralization with a minimum of equipment. Yet, lime remains the most widely used base for acid neutr zation. Limestone is used when reaction rates are slow and considerable time is available for reaction. Siilfuric acid is the primary acid used to neutralize high-pH wastewaters unless calcium smfate might be precipitated as a resmt of the neutralization reaction. Hydrochloric acid can be used for neutrahzation of basic wastes if sulfuric acid is not acceptable. For very weak basic waste-waters carbon dioxide can be adequate for neutralization. 

Hydrochloric Acid—Properties, Uses, Storage and Handling, E. 1. Du Pont de Nemours and Company, Wilmington, DE, September 1984. 

Hydrochloric acid (10-15 per cent) is generally used. If applied correctly it will remove laitence and provide an adequate surface for adhesion. It will not open up air pockets and voids and is difficult and hazardous to handle and apply. It is most suitable for use on floors. 

The austenitic irons are superior to ordinary cast iron in their resistance to corrosion by a wide range of concentrations of hydrochloric acid at room temperature (Table 3.50). However, for practical uses where such factors as velocity, aeration and elevated temperatures have to be considered, the austenitic irons are mostly used in environments where the hydrochloric acid concentration is less than 0- 5%. Such environments occur in process streams encountered in the production and handling of chlorinated hydrocarbons, organic chlorides and chlorinated rubbers. 

Fig. 3.63 Limits of use of silicon irons for handling hydrochloric acid solutions (former Ministry of Supply data) for Fe-18Si and Fe-14-5Si alloys...

Titanium impellers have been used in pumps employed for the conveyance of corrosive and erosive ore slurries, for organic chlorides containing hydrochloric acid and free chlorine , for handling moist chlorine gas, and in the wood-pulp and the textile-bleaching industry, particularly with sodium hypochlorite . 

Plants producing and handling halogens and halogen compounds Tantalum finds extensive use in the production and handling of hydrochloric and hydrobromic acid, chlorine and bromine and many of their derivatives. Absorbers, coolers and heaters which show considerable advantages in terms of heat-flux capabilities and corrosion resistance have been used on hydrochloric acid duties for over 40 years and condensers have been used in bromine plants for at least the same period. Typical applications of tantalum in the bromine and chlorine industries are listed in Table 5.27 . 

The crude enamine is dissolved in 450 ml. of ether, and the solution is transferred to a 1-1. three-necked flask equipped with a sealed stirrer, a 250-ml. dropping funnel, and a two-necked adapter fitted with a calcium chloride tube and a thermometer immersed in the solution. A solution of 71-76 g. (0.85-0.90 mole) (Note 5) of methyl propiolate (Caution Methyl propiolate is a severe lachrymator and should he handled only in the hood.) in 150 ml. of ether is added dropwise. During the addition the temperature of the mixture is maintained at 25-30° by periodic cooling of the reaction flask in a dry ice-acetone bath. When the addition is almost complete, a white solid begins to separate. The mixture is stirred at 25-30° for an additional hour, cooled to 0°, and filtered to remove the solid. This is dissolved in 700 ml. of 6% hydrochloric acid (Note 6), the acidic solution is warmed at 55-60° for 1 hour, and the mixture is cooled and extracted with two 100-ml. portions of ether. The ether is removed on a steam bath, and the residue of crude methyl 10-oxocyclodec-2-ene-l-carboxylate is dissolved in 300 ml. of methanol and hydrogenated over 5 g. of 5% palladium-on-alumina catalyst at 40 p.s.i. pressure and room temperature. 

Are there any hazardous substances stored or handled YES Organic feed materials concentrated hydrochloric acid oxygen... 

Hydrochloric acid. Strong acids are used frequently for the purpose of sample dissolution when water will not do the job. One of these is hydrochloric acid, HC1. Concentrated HC1 is actually a saturated solution of hydrogen chloride gas, fumes of which are very pungent. Such a solution is 38.0% HC1 (about 12 M). Hydrochloric acid solutions are used especially for dissolving metals, metal oxides, and carbonates not ordinarily dissolved by water. Examples are iron and zinc metals, iron oxide ore, and the metal carbonates of which the scales in boilers and humidifiers are composed. Being a strong acid, it is very toxic and must be handled with care. It is stored in a blue color-coded container. 

Hydrochloric acid HC1 Commercially available concentrated solution is 38% (12 M) HCl evolves pungent fumes and must be handled in fume hood Dissolving some metals and metal ores... 

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