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:
Jan. 18, 1977
Filed:
May. 17, 1976
Stefan Schafer, Bruhl, DT;
Alexander Ohorodnik, Erftstadt-Liblar, DT;
Klaus Gehrmann, Erftstadt-Lechenich, DT;
Albert Mainski, Rodenkirchen, DT;
Hoechst Aktiengesellschaft, Frankfurt am Main, DT;
Abstract
Crude hydrogen chloride gas obtained as a by-product in the production of chloroacetic acids by the catalytic chlorination of acetic acid with chlorine gas in contact with acetic anhydride and/or acetyl chloride, and contaminated with about 0.6 up to 3 % by volume of acetyl chloride is purified. To this end, crude hydrogen chloride gas is introduced into the base portion of a scrubbing zone and scrubbed countercurrently therein with 0.5 up to 20 liter, per normal cubic meter (S.T.P) of hydrogen chloride gas, of a cooled scrubbing liquid under circulation, consisting substantially of 20-80 weight % of concentrated H.sub.2 SO.sub.4, 15-60 weight % of acetic acid, and 5-50 weight % of water. The resulting purified moist hydrogen chloride gas issuing at the head of the scrubbing zone is introduced into the base portion of a drying zone and scrubbed countercurrently with precooled sulfuric acid under circulation.