Method for preparing 3-ethylbenzophenone

A method for preparing 3-ethylbenzophenone in a high purity which consists essentially of the steps of alkylating benzene with ethylene in the presence of an alkylating catalyst comprising aluminum chloride and at a temperature within the range of about 0.degree. C. to 175.degree. C. to obtain an alkylated product composed mainly of unreacted benzene, ethylbenzene, polyethylbenzene and heavier substances;

• subjecting said alkylated product to distillation in order to recover therefrom a fraction which has a boiling point temperature with the range of 275.degree. C. to 310.degree. C. (in terms of atmospheric pressure);
• heating said recovered fraction together with a mixture of nitric acid and water at a temperature within the range of about 30.degree. C. to 150.degree. C., said weight ratio of 100% nitric acid to water being within the range of 1:20 to 1:1, and said weight ratio of nitric acid (as 100% acid) to said fraction being with the range of 0.03:1 to 3:1 to produce 3-ethylbenzophenone, and performing distillation to recover therefrom 3-ethylbenzophenone represented by the formula (1):
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