The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 11, 1992
Filed:
Dec. 20, 1990
Kenichi Okamoto, Yamaguchi, JP;
Hidetoshi Kita, Yamaguchi, JP;
Yasuo Tanaka, Tokyo, JP;
Shigeru Iimuro, Aichi, JP;
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
A method for preparing 2,2-bis(4-hydroxyphenyl)propane comprises reacting acetone and phenol in the presence of an acidic ion-exchange resin as a catalyst wherein the reaction of acetone and phenol is performed while removing a part of the water generated during the reaction from a mixed solution containing acetone and phenol by a pervaporation method. According to the method, the water generated through the reaction can rapidly be removed simultaneously with or alternatively to the reaction by a pervaporation operation and, therefore, the catalytic activity of the ion-exchange resin is not impaired at all. Moreover, any complicated operations associated with the dehydration are not required. Thus, the acidic ion-exchange resin catalyst can continuously be used over a long time period without any treatment for the regeneration thereof. Further, according to the method, bisphenol A can be economically prepared from acetone and phenol in a high conversion rate and high yield.