Patent · US Expired

Process for the preparation of a particularly pure monochloroacetic

US5756840A · kind A · utility

4Cited by

1References

9Claims

0Family size

Assignee

Hoechst GmbH · DE

Inventors

Frank Ebmeyer · Hattersheim, DE
Detlef Kampmann · Bochum, DE
Ulf Otto Paulus-Von Russdorf · Gersthofen, DE
Rudolf Rossmeissl · Mertingen, DE

Key dates

Filing date	Dec 11, 1996
Grant date	May 26, 1998
Priority date	—
Expiry date	Dec 11, 2016

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C51/487
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.