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. 26, 1998
Filed:
Dec. 11, 1996
Applicant:
Inventors:
Frank Ebmeyer, Augsburg, DE;
Detlef Kampmann, Gersthofen, DE;
Ulf Otto Paulus-Von Russdorf, Gersthofen, DE;
Rudolf Rossmeissl, Mertingen, DE;
Assignee:
Hoechst Aktiengesellschaft, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562604 ;
Abstract
The present invention relates to a process for the preparation of a particularly pure monochloroacetic acid, in which, in a first step, a hydrogenation of a mixture of mono- and dichloroacetic acid is carried out to a residual content of dichloroacetic acid of 400 to 600 ppm and, in a second step, this mixture is subjected to melt crystallization. The hydrogenation is carried out with a heterogeneous catalyst which comprises 0.1-5.0% by weight of palladium and in which active charcoal or silicon dioxide is used as the support.