Patent ID: 6673245
Filing Date: 2004-01-06
Classification: B01D,C08B

Abstract:
The use of surface-active agents in the process of removing impurities from solutions containing acetic derivatives using nano-filtration membranes, in the process of obtaining cellulose acetate, wherein said process starting with aqueous solutions containing between 20 and 35% weight of acetic derivatives having been optionally decanted and filtered in a conventional manner in order to remove suspended impurities, which undergo the addition of one or more surface-active agents while submitted to a tangential filtration process via polymer membranes, the cutting range of which may vary between approximately 0.001 and 0.005 microns, and feed pressure which may vary between approximately 1 and 50 barg, at least one of the surface-active agents presents a component chosen from among the lignosulfonates.