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:
May. 21, 2002
Filed:
Jan. 21, 2000
Aldo Bertola, Milan, IT;
Myriam Hobe, Bas-Oha, BE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
An improved process for the production of high quality unsaturated dimethylesters by reacting dicarboxylic anhydrides, typically maleic anhydride or phthalic anhydride, with methanol. The process is characterized by the fact that the esterification is performed in two steps, the step 1 consisting in a non catalytic reaction of formation of monomethylesters, and the step 2 consisting in the catalytic reaction of formation of dimethylesters from the monomethylester, the said catalytic reaction taking place in a reactor consisting of a multi-tray column where the liquid phase containing the mono and diester mixture flows downwards from each tray coming to contact with a progressively drier upflowing stream of vapors in countercurrent, which continuously removes the water formed in the reaction from the liquid phase. The process uses an alkylbenzene sulfonic acid with an alkyl radical containing from 10 to 13 carbon atoms as esterification catalyst.