PROCESS FOR THE PRODUCTION OF 2,2-(4,4S-DIHYDROXYDIPHENYL)PROPAN E

摘要

1394957 2,2 - (4,41 - Dihydroxydiphenyl) propane SOC ITALIANA RESINE SIR SpA 26 Nov 1973 [30 Nov 1972] 54734/73 Heading C2C The invention comprises a process for the preparation of 2,2-(4,41-dihydroxydiphenyl)propane wherein (a) phenol is allowed to react with acetone in a molar ratio of at least 2 : 1 but not exceeding 10 : 1 in the presence of hydrogen chloride or hydrochloric acid as an acidic agent at a temperature not exceeding 80‹ C. to substantially complete reaction of the acetone; (b) the acidic agent is separated from the reaction product; (c) the product freed from hydrogen chloride is brought into contact with activated carbon or active earths at a temperature in the range of from about 60‹ to 120‹ C. for a time in the range of from about 1 to 120 minutes; (d) the product obtained in the treatment with the active material is distilled to recover the 2,2-(4,41-dihydroxydiphenyl) propane. By active earths is meant absorbents prepared from naturally occuring minerals. It is also possible to carry out the reaction in the presence of small quantities, in any case not exceeding about 5% by weight of the bisphenol finally formed, of an aromatic or paraffinic, chlorinated or unchlorinated hydrocarbon organic solvent whose boiling point is below 150‹ C.