Sulfuric acid world production

Table 2.2a. Sulfuric acid - world (production 000 tonnes 100% acid)...

Until the 1970s, the main production countries of sulfamic acid were the United States, several European countries, and Japan. The large amounts of dilute sulfuric acid by-product generated led to the difficult situation of by-product acid disposal. Concomitantly, the start of chemical production in developing Asian countries caused successional sulfamic acid production withdrawal in the 1980s. As of the mid-1990s production countries are Japan, Taiwan, Indonesia, India, and China. The 1995 world production capacity was ca 96,000 metric tons. 

Resources of Sulfur. In most of the technologies employed to convert phosphate rock to phosphate fertilizer, sulfur, in the form of sulfuric acid, is vital. Treatment of rock with sulfuric acid is the procedure for producing ordinary superphosphate fertilizer, and treatment of rock using a higher proportion of sulfuric acid is the first step in the production of phosphoric acid, a production intermediate for most other phosphate fertilizers. Over 1.8 tons of sulfur is consumed by the world fertilizer industry for each ton of fertilizer phosphoms produced, ie, 0.8 t of sulfur for each ton of total 13.7 X 10 t of sulfur consumed in the United States for all purposes in 1991, 60% was for the production of phosphate fertilizers (109). Worldwide the percentage was probably even higher. 

Sulfuric acid is the most important sulfur-containing intermediate product. More than 85% of the sulfur consumed in the world is either converted to sulfuric acid or produced direcdy as such (see Sulfuric acid and sulfur trioxide). Worldwide, well over half of the sulfuric acid is used in the manufacture of phosphatic fertilizers and ammonium sulfate for fertilizers. The sulfur source may be voluntary elemental, such as from the Frasch process recovered elemental from natural gas or petroleum or sulfur dioxide from smelter operations. 

In the early 1970s, air pollution requirements led to the adoption of the double contact or double absorption process, which provides overall conversions of better than 99.7%. The double absorption process employs the principle of intermediate removal of the reaction product, ie, SO, to obtain favorable equiUbria and kinetics in later stages of the reaction. A few single absorption plants are stiU being built in some areas of the world, or where special circumstances exist, but most industriali2ed nations have emission standards that cannot be achieved without utili2ing double absorption or tad-gas scmbbers. A discussion of sulfuric acid plant air emissions, control measures, and emissions calculations can be found in Reference 98. 

Because sulfuric acid has its greatest use in fertilizers, trends in that industry have a significant effect on the sulfuric acid business. Owing to a weak U.S. doUar in the early 1990s and high demand for fertilizer abroad, a considerable portion of U.S. phosphate fertilizer production was exported. High fertilizer exports are expected to continue until Thkd World countries can meet thek own demands. 

Yttrium and lanthanum are both obtained from lanthanide minerals and the method of extraction depends on the particular mineral involved. Digestions with hydrochloric acid, sulfuric acid, or caustic soda are all used to extract the mixture of metal salts. Prior to the Second World War the separation of these mixtures was effected by fractional crystallizations, sometimes numbered in their thousands. However, during the period 1940-45 the main interest in separating these elements was in order to purify and characterize them more fully. The realization that they are also major constituents of the products of nuclear fission effected a dramatic sharpening of interest in the USA. As a result, ion-exchange techniques were developed and, together with selective complexation and solvent extraction, these have now completely supplanted the older methods of separation (p. 1228). In cases where the free metals are required, reduction of the trifluorides with metallic calcium can be used. 

As world deposits of petroleum and coal are exhausted, new sources of hydrogen will have to be developed for use as a fuel and in the production of ammonia for fertilizer. At present, most hydrogen gas is produced from hydrocarbons, but hydrogen gas can also be generated by the electrolysis of water. Figure 19-23 shows an electrolytic cell set up to decompose water. Two platinum electrodes are dipped in a dilute solution of sulfuric acid. The cell requires just one compartment because hydrogen and oxygen escape from the cell much more rapidly than they react with each other. 

Chemists are not the only ones who make use of acid-base chemistry. In fact, most of the chemical manufacturing that goes on in the world is related to the production of four simple, but very useful, products—sulfuric acid, phosphoric acid, sodium hydroxide, and sodium chloride. 

The application of solvent extraction to copper recovery has been a major growth area since the last review of this series.11,13 Almost 30% of world production in 2000 involved the use of sulfuric acid heap leaching, solvent extraction, and electrowinning, far exceeding earlier predictions.136... 

Sulfuric acid is manufactured on an enormous scale with an annual output of around 90 billion pounds. During the mid-1900s (when the production of sulfuric acid was less than half what it is now), about a third of the sulfuric acid produced was used in the production of fertilizer, but that use rose to about two-thirds in the later 1900s. During that time the world population grew from perhaps 3 billion to about 6 billion. 

Ellis A process for making isopropyl alcohol from light olefin mixtures by treatment with concentrated sulfuric acid. Operated in World War I by the Melco Chemical Company, as an intermediate for the production of acetone for airplane dope. ... 

The sulfur dioxide is recovered as sulfuric acid and reconverted to sodium sulfate. Alumina hydrate is precipitated from the sodium aluminate by carbon dioxide. The process has not become widely accepted because the product is contaminated by silica, but it was used in Belgium before and after World War I and in Germany in the 1920s and 1940s. 

Cadmium also may be recovered from zinc ores and separated from other metals present as impurities by fractional distillation. Alternatively, the cadmium dust obtained from the roasting of zinc ore is mixed with sulfuric acid. Zinc dust is added in small quantities to precipitate out copper and other impurities. The metal impurities are removed by filtration. An excess amount of zinc dust is added to the solution. A spongy cadmium-rich precipitate is formed which may he oxidized and dissolved in dilute sulfuric acid. Cadmium sulfate solution is then electrolyzed using aluminum cathodes and lead anodes. The metal is deposited at the cathode, stripped out regularly, washed and melted in an iron retort in the presence of caustic soda, and drawn into desired shapes. More than half of the world s production of cadmium is obtained by elecrolytic processes. 

The most common current method of phenol production is from the cumene hydroperoxide rearrangement process. In this process, benzene reacts with propylene to produce cumene. Cumene is oxidized to cumene hydroperoxide. When cumene hydroperoxide is treated with dilute sulfuric acid, it rearranges and splits into phenol and acetone. Because the reactants are inexpensive and the process is simple, the acidic oxidation of cumene is used to produce more than 95% of the worlds supply of phenol. 

The lead-chamber process supplied the worlds need for sulfuric acid for a century and a half. In the late 19th century, the contact process replaced the lead-chamber process and is still used today to produce the world s supply of sulfuric acid. The contact process was first developed by Peregrine Phillips (1800- ), a British acid dealer, in 1831. The contact process used sulfur dioxide, S02, which was produced as a by-product when sulfur-bearing ores were smelted. The contact process was named because the conversion of sulfur dioxide to sulfur trioxide, S03, takes place on contact with a vanadium or platinum catalyst during the series of reactions ... 

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