METHOD FOR PRODUCING BISPHENOL A

摘要

PROBLEM TO BE SOLVED: To provide a method for producing bisphenol A at a high selectivity by a simple process in which the volume of a recombination reactor can be reduced and the using amount of energy is reduced in a recombination step of recombining phenol with isopropenylphenol to produce bisphenol A.SOLUTION: Disclosed is a method for producing bisphenol A characterized in that the molar ratio of phenol to isopropenylphenol fed to a step (G) is controlled to 3 to 18, and including: a step (A) of condensing acetone and phenol in the presence of an acidic catalyst to obtain a reaction liquid including bisphenol A: a reaction step (C); a crystallization solid-liquid separation step (F) of producing crystals made of the bisphenol A and phenol from the reaction liquid including the bisphenol A by crystallization and separating the crystals into the crystals and a mother liquor; a step (G) of heating and decomposing the mother liquid obtained from the crystallization solid-liquid separation step or a mother liquid treated material obtained by treating the mother liquid in the presence of an alkaline catalyst to recover phenol and isopropenylphenol; (H) a recombination reaction step of contacting the recovered phenol and the recovered isopropenylphenol with an acidic catalyst so as to be recombined and to obtain a reaction liquid including the bisphenol A; and a circulation step of circulating the reaction liquid obtained in the step (G) to the upstream by the step (C).