Patent ID: 6939961

Claim:
A process for the production of low-viscosity water-soluble cellulose ethers by oxidative decomposition of higher-viscosity cellulose ethers with hydrogen peroxide, comprising: (a) forming, under conditions of intensive mixing and at temperatures of 65-125° C., a mixture comprising, (i) higher-visocity cellulose ethers, and (ii) an aqueous solution of hydrogen peroxide which is present in an amount of 0.5 to 1.8 wt % in relation to the dry cellulose ether, the solid content of the mixture is no lower than 25 wt % in relation to the total quantity of the mixture; and (b) agitating continuously the mixture of step (a) at temperatures of 65-125° C. until approximately at least 90% of the hydrogen peroxide has been spent, wherein during or after the decomposition reaction, the pH value of the mixture of step (a) is set at more than 4.5, by adding to said mixture a second aqueous solution which has a pH of 5 to 12, provided that when said second aqueous solution is added during the decomposition reaction said second aqueous solution may optionally contain, in solution, the hydrogen peroxide required for the decomposition reaction.