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:
Mar. 19, 1996
Filed:
Dec. 03, 1992
Applicant:
Inventors:
Heinz Wallisch, Eltville, DE;
Reinhard Donges, Bad Soden am Taunus, DE;
Ulrich Meyer-Blumenroth, Idstein, DE;
Assignee:
Hoechst AG, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C02F / ; C08B / ; C08B / ;
U.S. Cl.
CPC ...
210651 ; 210758 ; 210759 ; 210760 ; 210702 ; 536 85 ; 536 91 ;
Abstract
The invention relates to a process for the purifying working-up of liquid reaction media and/or wash media obtained during preparation of cellulose ethers, which are insoluble in hot water, from cellulose, an alkali metal hydroxide and at least one etherifying agent in a medium containing water and if appropriate at least one organic solvent, by ultrafiltration of the media into a permeate and concentrate, which comprises carrying out the ultrafiltration of the reaction media and/or wash media at a temperature at or above the flocculation temperature of the cellulose ethers.