Patent ID: 6130328
Filing Date: 2000-10-10
Classification: C08B

Abstract:
A process for preparing a carboxypolysaccharide, comprising a first step of oxidizing a polysaccharide with a combination of a transition metal compound and an oxidizing agent, to form a reaction mixture, and a second step of separating the transition metal compound from the reaction mixture with a chelating agent, wherein the step of separating the transition metal comprises (1) a step in which the reaction mixture is treated with the chelating agent, and (2) a step in which the transition metal is extracted and removed with a water-insoluble organic solvent, and wherein the chelating agent is a dithiocarbamate represented by the formula R.sup.1 R.sup.2 N--C(.dbd.S)--SM wherein R.sup.1 and R.sup.2 are each hydrogen, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 14 carbon atoms; and M is a metallic element cation.