Catalyst continued manganese-containing

The first step is a liquid phase air oxidation of toluene to benzoic acid. Air and toluene are fed continuously into the base of an autoclave containing benzoic acid and a cobalt acetate-manganese acetate catalyst at 110—150°C and about 3 atmospheres. About 50% of the toluene is converted per pass. The unreacted toluene is removed and recycled and the residual crude benzoic acid is purified by distillation or crystallization. In the second step benzoic acid, containing cupric benzoate as catalyst and magnesium benzoate as promoter, is heated to 230—240°C. Steam and air are passed into the melt. Phenol and benzoic acid are vaporized continuously and are separated by distillation. The overall yield of phenol is 70-75%. 

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