To provide a method for producing sorbic acid in high yield while significantly decreasing the amount of tar formed in the decomposition of a polyester and lowering the treating load of waste filtrate in a purification step.
The method for the production of sorbic acid comprises the reaction of crotonaldehyde with ketene and the hydrolysis of the obtained polyester with hydrochloric acid solution having a concentration of ≤15 wt.% under pressure or at ≤100°C. The hydrolysis of the polyester may be carried out at 115-140°C using hydrochloric acid solution having a concentration of 3-10 wt.%. The filtrate obtained by the solid-liquid separation of the reaction mixture obtained by the hydrolysis may be recycled to the step for the hydrolysis of the polyester.
MITANI TADAYOSHI
KAMEI NOBORU
