Sulphuric acid production

Platinum is used as a catalyst for nitric and sulphuric acid production, in petroleum refining and in catalytic mufflers to control air pollution. Platinum salts can cause respiratory complaints, asthma, and platinosis , an allergic response. Allergic dermatitis may also result from exposure to soluble platinum salts and once subjects have been sensitized it generally precludes continued occupational exposure at any level. The 8 hr TWA OEL for platinum metal is 5 mg/m but for soluble platinum salts it is only 0.002 mg/m. Handling precautions must include containment where possible, ventilation, personal protection, and the screening out of individuals who have become sensitized. 

Bunimovich, G. A., Strots, V. O., and Goldman, O. V., Theory and industrial application of S02 oxidation reverse-process for sulphuric acid production, in Unsteady-state Processes in Catalysis (Matros, Yu. Sh., Ed.). VNU Science Press, Utrecht, 1990, pp. 7-24. 

Matros, Yu. Sh., Unsteady-state oxidation of sulphur dioxide in sulphuric acid production. Sulphur 183, 23 (1986). 

Sulphuric acid is the largest volume chemical in the world with an annual production of about 180 mill, t/year which is used primarily for phosphate fertilizers, petroleum alkylation, copper ore leaching and in smaller quantities for a number of other purposes (pulp and paper, other acids, aluminium, titanium dioxide, plastics, synthetic fibres, dyestuffs, sulphonation etc.). The major sulphur sources for sulphuric acid production are sulphur recovered from hydrocarbon processing in the refineries and from desulphurisation of natural gas, SO2 from metallurgical smelter operations, spent alkylation acid, and to a minor extent mined elemental sulphur and pyrites. A simplified flow sheet of a modem double-absorption plant for sulphuric acid production from sulphur is shown in Fig. 1. 

Today, solid-catalyzed gas reactions are executed to an extent of several billions of tonnes per annum. To name only a few important examples Steam reforming of methane-rich natural gas to synthesis gas (H2 + CO), conversion of CO with H20 to C02 + H2, conversion of CO with H2 to methane, ammonia synthesis, oxidation of S02 to S03 (sulphuric acid production), oxidation of NH3 to NO (nitric acid production). The world production of ammonia in 1995 amounted to 90 m tonnes and... 

SOx group discharges have dropped 30% since 1992. Between 1988 and 1998 discharges from the 35 French sites fell from 25 000 tonnes to 15000 tonnes. 75% of these emissions are from fuels, the remainder being primarily from sulphuric acid production ... 

Low amounts enter into the atmosphere during sulphuric acid production, during the production of phosphate fertilizers, and during electroplating, etc. 

Bulicka, M. and Podmoh k, J. In Proc. of the Conf. Problems of the Sulphuric Acid Production. Dom techniky 6SVTS, llstf n. Labem 1972, p. 40 (in Czech). 

High levels of SOx are generated in the furnace offgas to optimise sulphuric acid production. The use of oxygen enrichment to 50% in the process gas results in SOx concentrations of 12% -16% at the furnace offtake. The effect of air ingress on the gas strength at the acid plant is to reduce this figure to typically 10% -14%. 

Main reactor with lead lining Reaction of AH with sulphuric acid Production affected severely Immediate repairs required... 

The diversity of sources of inorganic chemicals was touched on in the introduction to this chapter and the book entitled The Modern Inorganic Chemicals Industry discusses, in detail, the production of a number of important inorganic chemicals. Comment here therefore will be restricted to a summary of world consumption (Table 2.6) and major uses of the more important inorganic raw materials, plus a brief study of the changing raw-material usage for sulphuric acid production and the reasons for this. Between 1960 and 1975 four alternatives were utilized in sulphuric acid production. They are sulphur, anhydrite (a calcium sulphate mineral), zinc concentrates... 

Figure 1.2 Basic process flow diagram for sulphuric acid production heal removal essential at every stage...

A chemical engineer concerned with sulphuric acid production would be aware of all the processes given in the tables but most familiar with only those of direct concern. These include filtration, drying and acid spray/mist removal. 

One point of interest is that more sulphur-containing compounds are emitted from coal-burning power stations than are required for sulphuric acid production in the UK, and a major development may be to consider this as a... 

Another part of the integration is that the biological waste water treatment plant treats all the waste waters from the site as well as the municipal waste water. The off-gas treatment for the production of viscose is combined with a sulphuric acid production unit. Gases containing sulphur can also be used as combustion air in various combustion plants with flue-gas desulphurisation. Additionally, the supply networks for steam and process water are highly sophisticated. 

The exhaust gases are cooled and steam saturated when they enter the adsorbers. The lower sections of the adsorbers are filled with activated carbon which is impregnated with potassium iodide (KI) to facilitate the conversion of H2S to elementary sulphur. The adsorbed sulphur is used for sulphuric acid production as described in Section 12.7.4.2 after being desorbed by CS2 and subsequent evaporation of CS2 and distillation. 

The reaction of sulphur dioxide with oxygen to form sulphur trioxide is industrially the most significant of all its reactions because of its importance in sulphuric acid production. In the gas phase, it will only take place at elevated temperatures and, for a satisfactory yield of sulphur trioxide it requires the presence of a catalyst. In aqueous solution, sulphur dioxide is oxidized to sulphuric acid at low temperatures by air in the presence of activated coke or nitrous gases or by oxidizing agents like hydrogen peroxide. 

Throughout the rest of the period under review the chemical technology came to Denmark from, or at least via, Germany 1873, beet sugar 1880 (approx.), Gay-Lussac and Glover towers in sulphuric acid production 1888, Portland cement and 1900 (approx.), refining of edible oil. 

Sulphuric acid production grew from 71,500 tons in 1898 to 650,000 tons in 1913. Before World War I some 80 per cent of the sulphuric acid produced was used in the manufacture of fertilizers only 18,000 tons of acid were utilized by the explosives and chemical industry. During the war, the explosives industry consumed 160,000 tons of acid. 

Arsenic compounds could still be detected in the water after industrial practice had shifted to the use of nitrobenzene as oxidant in the production of magenta. These residues were the result of sulphuric acid production, as sulphurous non-ferrous ores usually contained arsenic. F. Fischer, Ueber die Verunreinigung der Fliisse durch Industrie- und stadtische Abfallstoffe und die Mittel dagegen . Dingier s Polytechnisches Journal, 211 (1874), 200-227, p. 202. Fischer calculated that 1,500,000 kg of arsenic per year were fed into rivers as a result of sulphuric acid production. 

For greater apparatuses, especially in sulphuric acid production the ceramic supporting plate presented in Fig. 16 can be used. 

Louie, D., 2010b. Design considerations for sulphuric acid plants. In Paper in Short Course Sulphuric Acid Production Technologies Given at Cobre-Copper 2010, Hamburg, June 6-10, 2010. 

---