METHOD OF PURIFYING BISPHENOL A CONTAINING PHENOL

摘要

A method which includes: a first step in which crude molten bisphenol A containing phenol is supplied to a flash evaporator to separate it into a gas phase comprising phenol and a liquid phase comprising bisphenol A and the residual phenol; and a second step in which the liquid phase obtained in the first step is heated with a thin-film evaporator to separate it into a liquid phase comprising phenol and a liquid phase comprising the bisphenol and the residual phenol and having an increased bisphenol A concentration. In the method, part of the liquid phase obtained in the second step is circulated to the first step and supplied to the flash evaporator together with crude molten bisphenol A. Thus, high-quality bisphenol A can be stably obtained from phenol-containing bisphenol A.