| 摘要 |
<p>PURPOSE: To obtain colorless bisphenol A having a high quality and prevented from the accumulation of impurities in the reaction system by depositing off the adduct of bisphenol A to phenol from a reaction mixture and subsequently subjecting the left mother liquid to a specific treatment. CONSTITUTION: An excessive amount of phenol is condensed with acetone in the presence of a strong acidic cation exchange resin, and the reaction mixture is concentrated in many stages. The concentrate is cooled to deposit the crystals of the bisphenol A-phenol adduct, and the mother liquid is separated. The phenol is removed from the adduct to give the bisphenol A. A part of the mother liquid after the separation of the adduct is isomerized with a strong acidic cation exchange resin in the process 7, and subsequently recycled into the condensation reaction process 1, the first and second concentration processes 2, 3 or the first crystal-depositing process. The left mother liquid is concentrated in the process 8 and subsequently cooled to deposit the bisphenol A-phenol adduct as crystals. The liquid phase part left after the separation of the adduct is heated in the process 11 to recover the phenol.</p> |
