Abstract
In 1959 Sumitomo Chemical Co. invented the low toxic insecticide Fenitrothion (trade name : Sumithion). In 1960s the demand of 2, 6-ditertiary butyl-4-methyl phenol (BHT), a fundamental antioxidant for polymers, was getting bigger and bigger, as the polymer industry in Japan grew up sharply.
The starting material of Fenitrothion is m-cresol and the one of BHT is p-cresol. The demand of m, p-cresol for exceeded the supply from the coal and the petroleum industry. The development of the manufacturing process of m, p-cresol turned an important theme for Sumitomo Chemical Co.
Sumitomo Chemical Co. studied the several processes and decided to adopt to cymene process that was consisted of the isopropylation, oxidation and cleavage of toluene. The cymene process was studied at a laboratory stage in 1965 and at a pilot plant stage in 1968. The m, p-cresol plant via cymene started in the end of 1969 with an annual production capacity 20, 000 ton at Sumitomo Chemical Co. Ohita work and this was the first cymene process m, p-cresol plant in the world. This plant has met an increasing demand of the insecticide and the antioxidant.
