Patent ID: 8143456

Claim:
A method of separating methanol from acetone recycle streams during production of bisphenol-A, comprising: (a) introducing a product stream, including acetone, methanol, water and other components produced during a bisphenol process, as a feed at a feed point into an acetone recovery distillation column comprising a reboiler, a condenser, a bottom section, and a top section; (b) condensing a vapor from the top section of the acetone recovery distillation column and returning at least a portion of the condensed vapor to the acetone recovery distillation column as a reflux; and (c) setting a flow rate of the feed and a flow rate of the reflux and a heat input to the reboiler such that a bottoms product from the bottom section of the acetone recovery distillation column contains less than 10,000 ppm acetone; wherein at least 20% of the methanol of the feed to the acetone recovery distillation column is leaving with the bottoms product from the bottom section of the acetone recovery distillation column.