Patent ID: 9115216
Filing Date: 2015-08-25
Classification: C08B

Abstract:
1. A method for producing cellulose ether, comprising at least the steps of: bringing a pulp into contact with an alkali metal hydroxide solution to obtain a contact product, draining the contact product by a drainer to obtain an alkali cellulose, reacting the alkali cellulose with an etherifying agent, reusing an alkali metal hydroxide solution recovered in the step of draining continuously for contact with a pulp in the step of bringing, and adjusting an amount of cellulose particles in the recovered alkali metal hydroxide solution to 0.5% by weight or less prior to reusing for contact with the pulp, wherein the step of adjusting comprises removing a foam layer from the recovered alkali metal hydroxide solution, and said removing a foam layer is selected from the group consisting of removal by overflow, removal by suction, removal by scraping using a blade-like device, and removal by skimming using a ladle-like device.