India sulfuric acid manufacturing

Unlike the above scenario for India, sulfuric acid manufacture in Europe, UK, and USA have flourished since the mid-nineteenth century. 

Sulfuric Acid. Until the 1940 s the manufacture of heavy chemicals in India was insignificant. The production of sulfuric acid was only 18,000 tons as contrasted with 7,000,000 tons in the United States at the same time. Until the establishment of the first contact acid plant in 1948, all production used the chamber process. Installed annual capacity in 1948 was 175,000 tons, distributed among 49 different units. Because India does not have a source of free sulfur, the production of sulfuric acid is one of the critical chemical industries. India, however, has large deposits of iron pyrite in the northern part of the country and development of these is being undertaken to alleviate the problem of the lack of sulfur. 

Appendix History of Manufacture of Sulfuric Acid (in India and Other Countries)... 

Sulfuric acid in India became the key for the manufacture of chemicals in the twentieth century. 

DDT may be manufactured (DDT is currently only manufactured in India, for the control of the insect vectors of malaria and visceral leishmaniasis) from chlorobenzene and chloral (CCI3CHO) in the presence of sulfuric acid. Write a mechanism for the process. Only about 77 % of commercial DDT is actually the compound of which we generally write the structure. Commercial samples contain 15 % of 25.1 and smaller amounts of 25.2 and 25.3. Explain how these compounds could arise from the synthesis. 

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