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:
Aug. 21, 1990
Filed:
Feb. 14, 1989
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
A process for producing high-purity bisphenol A comprises reacting phenol with acetone in the presence of hydrochloric acid as the catalyst to obtain a product mixture, removing the hydrochloric acid from the product mixture, thereby yielding a liquid mixture, adding water to the liquid mixture, evaporating a water-phenol mixture from the liquid mixture under reduced pressure, thereby cooling the liquid mixture and crystallizing out the adduct of bisphenol A with phenol, and finally recovering bisphenol A from the adduct, wherein an improvement comprises treating the water-phenol mixture with a weakly basic ion-exchange resin and recycling and reusing the treated mixture as the water to be added to the liquid mixture. This process does not causes any troubles such as the corrosion of equipment and the decomposition and discoloration of bisphenol A during distillation.