Sulfuric acid manufacturing process

Figure 8-14 Flowsheet of a sulfuric acid manufacturing process. [Reprinted wilii permission of the AIQiE and L. J. Friedman. Copyright 1982 AIChE. All rights reserved.]...

This process was not acceptable for several reasons low yields, poor quaUty, and the high cost of bromine. Later, at BASF, a process was developed for the manufacture of ali2artn by the caustic fusion of anthraquinone-2-sulfonic acid (so-called silver salt) which was made by sulfonating anthraquinone with sulfuric acid. This process was patented in England on the 25th of June, 1869. One day later, W. Perkin appHed for a patent for the manufacture of ali2ariQ by a process almost identical to the German process except that the "silver salt" was prepared as follows ... 

Longmaid-Henderson A process for recovering copper from the residue from the roasting of pyrites to produce sulfur dioxide for the manufacture of sulfuric acid. The residue was roasted with sodium chloride at 500 to 600°C the evolved sulfur oxides and hydrochloric acid were scrubbed in water and the resulting solution was used to leach the copper from the solid residue. Copper was recovered from the leachate by adding scrap iron. The process became obsolete with the general adoption of elemental sulfur as the feedstock for sulfuric acid manufacture. 

Miles, F. D., The Manufacture of Sulfuric Acid (Contact Process), Gurney Jackson, London, 1925, Chap. 10. 

PuraSiv S A process for removing sulfur dioxide from the tail gases from sulfuric acid manufacture by adsorption on a special zeolite. Not to be confused with PuraSiv HR, Type S. 

Reinluft A flue-gas desulfurization process using coke. The carbon acts as a catalyst for the oxidation of the sulfur dioxide to sulfur trioxide in the presence of water, and the sulfur trioxide is retained on the coke. The coke is regenerated in another vessel by heating with a hot gas stream, which reduces the sulfur trioxide back to sulfur dioxide and expels it for use in sulfuric acid manufacture. The key to this process is the inexpensive adsorbent. Developed by Reinluft GmbH and Chemiebau Dr. A. Zieren GmbH, and marketed as the Reinluft (Clean Air) Process. Four plants had been built by 1985. 

DOT safety regulations, 25 337 Double absorption process, for sulfuric acid manufacture, 23 769 Double absorption sulfuric acid plants, 23 774... 

Sulfuric Acid. Essentially all sulfuric acid manufactured in this industry is produced by the contact process, in which SO2 and oxygen contact each other on the surface of a catalyst (vanadium pentaoxide) to form SO3 gas. Sulfur trioxide gas is added to water to form sulfuric acid. The sulfur dioxide used in the process is produced by burning elemental sulfur in a furnace. 

Early epidemiological studies suggested an association between the manufacture of isopropyl alcohol and paranasal sinus cancer/ The risk for laryngeal cancer may also have been elevated in these workers. The increased cancer incidence, however, appears to be associated with some aspect of the strong-acid manufacturing process rather than the isopropyl alcohol itself It is unclear whether the cancer risk is due to the presence of diisopropyl sulfate, which is an intermediate in the process, to isopropyl oils, which are formed as byproducts, or to other agents, such as sulfuric acid. ... 

Figure 2.3 Contact process for sulfuric acid manufacture.

Sulfur trioxide is produced as an intermediate in manufacturing sulfuric acid by the contact process (See Sulfuric Acid). The process involves catalytic oxidation of sulfur dioxide to trioxide. 

Of the approximately 40 million tons (36 million metric tons) of sulfuric acid manufactured in the United States per year, about 90% is used in the production of fertilizers and other inorganic chemicals. Much of the remaining 10% of H2SO4 is used by the petroleum, petrochemical, and organic chemicals industries. Much of this latter acid is involved in recycling kinds of processes. As pollution regulations in various countries become more restrictive, spent acid may become a much more attractive raw material than has been the case in the past. 

Sulfuric acid from manufacturers 1 and 6 were sent to our laboratory for analysis by a client who had yield problems when using sulfuric acid from manufacturer 1 but no problems with sulfuric acid from manufacturer 6. The total trace element concentration in the sulfuric acid from manufacturer 1 was about four times higher than that from manufacturer 6. Low trace element concentrations were also found in sulfuric acids from U.S. (manufacturer 7) and Japanese (manufacturer 8) manufacturers. Sulfuric acid from manufacturer 9 had the lowest trace metal content. This sulfuric acid was processed through an acid reclaim system and was purer than the unused sulfuric acid put into the reclamation unit. 

The contact process has evolved to become the method of choice for sulfuric acid manufacture because of the ability of the process to produce stronger acid. 

Fig. 25.9. Schematic flow diagram of a double absorption contact process for sulfuric acid manufacture.

The book begins with a 9 chapter description of sulfuric acid manufacture. These chapters introduce the reader to industrial acidmaking and give reasons for each process step. They also present considerable industrial acid plant operating data. We thank our industrial colleagues profusely for so graciously providing this information. 

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