Process for preparing a bisphenol.

摘要

Bisphenols are prepared by a) reacting a phenolic compound with a carbonyl compound in a reaction mixture, containing the carbonyl compound, a stoichiometric excess of the phenolic compound and a catalyst, to produce a product mixture containing a bisphenol, b) separating bisphenol from the product mixture to leave a mother liquor and c) recycling at least a portion of the mother liquor to the reaction mixture. At least a portion of the phenolic compound is contacted with a strongly acidic cation exchange resin and a strongly basic anion exchange resin before the phenolic compound is used in the reaction step a) and/or at least a portion of the product mixture and/or at least a portion or the mother liquor is contacted with a strongly acidic cation exchange resin and a strongly basic anion exchange resin before mother liquor is recycled to the reaction mixture.