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:
Jul. 18, 2006
Filed:
Jan. 26, 2005
Rainer Neumann, Bad Tölz, DE;
Ulrich Blaschke, Krefeld, DE;
Stefan Westernacher, Kempen, DE;
Bayer Materialscience AG, Leverkusen, DE;
Abstract
A process for producing bisphenol A is disclosed. The process entails a) reacting phenol with acetone in the presence of an acidic catalyst to form a reaction mixture that includes bisphenol A and water, and b) removing water from the reaction mixture by distillation in a column to obtain a bottom product, and c) separating bisphenol-A/phenol adduct from the reaction mixture by crystallization and filtration. The bottom temperature of the column is 100 to 150° C., the overhead temperature of the column is 20 to 80° C., the absolute pressure is 50 to 300 mbar at the head of the column and 100 to 300 mbar at the bottom of the column, and wherein said (c) is carried out before or after said (b).