Patent ID: 6011184
Filing Date: 2000-01-04
Classification: C07C,Y02P

Abstract:
A process for the batch, semi-continuous, or continuous manufacture of bisphenol-A by condensing phenol with acetone, comprisingforming a reaction mixture comprising acetone, an excess of the phenol and a catalytic amount of an acid catalyst in a reaction zone and at a temperature effective to produce bisphenol A and a 1:1 bisphenol-A/phenol adduct;removing an effluent from the reaction zone, wherein the effluent comprises unreacted phenol, unreacted acetone, and the 1:1 bisphenol-A/phenol adduct;precipitating crystals of the adduct from the reaction mixture, the effluent, or a mixture thereof, wherein at least a portion of the crystals become affixed to a surface of the reactor; andremoving at least a portion of the precipitated crystals from the surface by adding water to the reaction mixture, the effluent, or a combination thereof, in an amount of 1-40% by weight of the reaction mixture, the effluent, or the combination thereof, and heating or maintaining the reaction mixture, the effluent, or a combination thereof at a temperature effective to dissolve the crystals.