Liquid wastes sulfuric acid

The residue of a sample of olein chloride (crude oleoyl chloride) was tipped into a waste container containing acid tars (70-80% waste sulfuric acid). There was a vigorous reaction, with gas evolution, which sprayed the analytical technician involved with the liquid contents of the container, causing bums. 

The seepage and leaking of sulfuric acid solutions used in leaching can also produce liquid wastes however, this potential is offset by the copper producer s interest in collecting as much of the copper-bearing leachate as possible. Older operations generally do not have protective liners under the piles and experience some loss of leachate. New leaching operations use impermeable membranes to confine leach solutions and channel them to collection ponds. 

Hydrogen sulfide is released primarily as a gas and will spread in the air. However, in some instances, it may be released in the liquid waste of an industrial facility. When hydrogen sulfide is released as a gas, it may form sulfur dioxide and sulfuric acid in the atmosphere. Sulfur dioxide can be further broken down and is a major contributor to acid rain. Hydrogen sulfide is estimated to remain in the atmosphere for an average of 18 hours. You will find more about what happens to hydrogen sulfide when it enters the environment in Chapters 4 and 5. 

Ross, F. F., Water Waste Treatment, 1964, 9, 528 private comm., 1966 One of the reagents required for the determination of dissolved oxygen in polluted water is a solution of sodium azide in 50% sulfuric acid. It is important that the diluted acid should be quite cold before adding the azide, since hydrogen azide boils at 36°C and is explosive in the condensed liquid state. 

Process Alternatives. Sulfur dioxide removal processes can be categorized as throwaway or recovery. Throwaway processes produce a liquid or solid waste that requires disposal. Recovery processes convert the sulfur dioxide to elemental sulfur or sulfuric acid. Throwaway processes have been used in most utility applications, but there could be greater incentives for using the recovery processes in industry. 

Environmental Protection. During the reduction of barite and the calcination of Sachtolith and lithopone, sulfur dioxide is liberated. This is removed from the waste gas in a purification stage which is based on the reversible, temperature-dependent solubility of sulfur dioxide in poly glycol. The absorbed sulfur dioxide can be recovered as a liquid product or as a raw material for sulfuric acid. Any soluble barium in the residue from the dissolution of the fused BaS is removed by treatment with... 

Wear protective gloves, laboratory coat, and goggles. Work in the fume hood. Add sufficient 3 M sulfuric acid (1.7 mL of concentrated sulfuric acid slowly added to 8.3 mL of cold water) to the waste to produce a solution not more than 5% in l-methyl-3-nitro-l-nitrosoguanidine. For each 10 mL of solution, add 0.5 g of potassium permanganate to give a 0.3 M solution. Stir the mixture at room temperature for 12 hours. Neutralize by cautiously adding soda ash or 10% aqueous sodium hydroxide solution, and then add, while stirring, a saturated aqueous solution of sodium bisulfite (approximately 10 g of sodium bisulfite per 35 mL of water) until a colorless liquid is formed. Wash into the drain with water. 10... 

Wear gloves and eye protection. The powder can be swept up and discarded as for waste disposal. For spills of solutions of Picloram, cover with a 1 1 1 mixture of sodium carbonate or calcium carbonate, clay cat litter (bentonite), and sand. Scoop the mixture into a container and add to a pail of water. Acidify the liquid by the careful addition of 3 M sulfuric acid (8 mL of concentrated sulfuric acid added to 42 mL of water) to pH 1. Estimate the weight of Picloram in the spill and add 5 g of potassium permanganate for each 0.3 g of Picloram. Stir thoroughly and allow it to stand at room temperature overnight. Reduce the excess permanganate by the addition of sodium bisulfite until no... 

The sulfate process has traditionally used batch ore digestion, in which concentrated sulfuric acid is reacted with ilmenite. This reaction is very violent and causes the entrainment of sulfur oxides (SOA) and sulfuric acid in large amounts of water vapor. In an effort to reduce the particulate emissions, scrubbers have been installed at most plants, but these, in turn, have necessitated the treatment of large quantities of scrubbing liquid before discharge. Other waste-disposal problem products are spent sulfuric acid and copperas (FeS04-7H20). 

When the reaction is complete, add 5 mL of 3 mol/L sulfuric acid while stirring or swirling the solution. This removes any unreacted zinc but does not affect the copper metal. Carefully decant the liquid into a clean waste container. Wash the copper metal carefully several times with water. Return the copper metal to your teacher. Wash your hands. This... 

Conventional sulfuric acid and HF alkylation processes ( >2, ) employ liquid-liquid catalytic systems which are expensive and troublesome because of such problems as maintaining an acid/hydrocarbon emulsion, product separation and waste disposal (H2SO4 process only). A solid catalyst should eliminate many of these problems. In view of their high activity, zeolites have been used by a number of workers (4,5,6,2) cata-... 

Neutralization Acidic or basic wastewaters must be neutralized 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. Equalization basins can be used as neutralization basins. When separate chemical neutralization is required, sodium hydroxide is the easiest base material to handle in a liquid form and can be used at various concentrations for in-line neutrafiza-tion with a minimum of equipment. Yet, lime remains the most widely used base for acid neutralization. Limestone is used when reaction rates are slow and considerable time is available for reaction. Sulfuric acid is the primary acid used to neutralize high-pH wastewaters unless calcium sulfate might be precipitated as a result of the neutralization reaction. Hydrochloric acid can be used for neutralization of basic wastes if sulfuric acid is not acceptable. For very weak basic waste-waters carbon dioxide can be adequate for neutralization. 

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