Method and device for preparing modified cellulose

Abstract

The invention relates to a method and a device for preparing modified cellulose, the device comprises a reaction kettle, the reaction kettle is internally provided with a solid-liquid space for reaction and a gas phase space for accommodating gas overflowing from the solid-liquid space, an outer circulation system is arranged outside the reaction kettle, the inlet end of the outer circulation system is communicated with the gas phase space in the reaction kettle, the inlet end of the outer circulation system is communicated with the gas phase space, and the outlet end of the outer circulatingsystem extends into the reaction kettle. The device is used for preparing hydroxypropyl methyl cellulose, hydroxyethyl methyl cellulose and other substances from cellulose, when cellulose etherification reaction is carried out, liquid in the solid-liquid space is heated and gasified, enters the gas-phase space firstly and then circularly enters the reaction kettle through the outer circulation system, so that the pressure in the kettle can be reduced, and the overall safety performance is guaranteed, the pressure resistance and sealing performance of the reaction kettle can be reduced, meanwhile, the liquid continuously passes through the outer circulation system and returns into the reaction kettle, so that the reaction liquid in the reaction kettle is always in an excessive state, the reaction speed is high, and the production efficiency is high.

Description

technical field [0001] The application relates to a method and device for preparing modified cellulose. Background technique [0002] Both hydroxypropyl methylcellulose (HPMC) and hydroxyethyl methylcellulose (HEMC) are non-ionic cellulose ethers, which are easy to dissolve in water and have good thickening, suspension, dispersion, emulsification, adhesion, Film-forming, water-retaining, and colloidal protection properties have been widely used in coatings, construction, medicine, food, textiles, papermaking, and polymer polymerization. [0003] The cellulose ether reactor is divided into horizontal reactor or vertical reactor, which can be used as a reaction device alone or with a cooler as a reaction device. [0004] The reactor used alone is suitable for the slurry process, the etherification agent is dissolved in an inert organic solvent, and the reaction pressure is generally low, below 0.6MPa. However, this kind of process reactor has a small amount of feed, long rea...

AI Technical Summary

Problems solved by technology

However, this kind of process reactor has a small amount of feed, long reaction time, and low production efficiency; the inert organic solvent needs to be recycled and reused, causing great pollution and high cost

Images