A kind of method for continuously preparing cellulose ether

A technology of cellulose ether and cellulose, which is applied in the field of continuous preparation of cellulose ether, can solve the problems of harming human health and hindering the characteristics of cellulose ether, and achieve the effect of simple operation

Active Publication Date: 2020-04-07
SHIN ETSU CHEM IND CO LTD
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Some of these by-products hinder the properties of cellulose ethers and are substances harmful to human health

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A kind of method for continuously preparing cellulose ether
  • A kind of method for continuously preparing cellulose ether

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] As a first preparation of cellulose ether, 100 parts by weight of pulp powder were placed in an autoclave with an internal stirrer, and the autoclave was fully purged with nitrogen. With stirring at 60°C, 45 parts by weight of dimethyl ether and 250 parts by weight of 49% by weight sodium hydroxide aqueous solution were simultaneously sprayed into the pulp in the autoclave over 20 minutes to prepare Alkaline cellulose. Then, 160 parts by weight of methyl chloride and 50 parts by weight of propylene oxide were additionally added, and reacted at 60° C. to 90° C. for 2 hours.

[0054] The exhaust gas after the completion of the reaction was recovered by using a partial condenser adjusted to a temperature of 20° C. and a recovery pressure of 2.0 MPa. The unintended liquid components liquefied in the partial condenser are recovered to the storage tank. The liquid components in the partial condenser were analyzed using a gas chromatograph manufactured by Shimadzu Corporatio...

Embodiment 2

[0058] Incineration was carried out in the same manner as in Example 1 except that some components to be recycled were incinerated together with components not to be recycled in the combustion furnace. Specifically, the liquid in the storage tank storing the liquid components that are not intended to be reused after being separated by the partial condenser and the liquefied gas components in the recovery tank are incinerated in the combustion furnace, so The liquefied gas components have not been reused in the second cellulose ether preparation after being separated with a partial condenser and liquefied with a total condenser. The object to be incinerated in the furnace contains 60% by weight of liquefied gas components from the recovery tank and 40% by weight of liquid from the storage tank.

[0059]The furnace temperature was 950°C. The liquefied gas component of the solution of dimethyl ether and unreacted methyl chloride is supplied from the recovery tank to the combusti...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
lengthaaaaaaaaaa
lengthaaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The present invention provides an efficient and continuous process for the production of cellulose ethers containing reduced amounts of insoluble components. Specifically, the method includes a contacting step of contacting pulp with an alkali metal hydroxide solution in the presence of a heat-removing solvent to obtain alkali cellulose; a reaction step of reacting the alkali cellulose with an etherifying agent; reacting Upon completion, partially condensing the gas present in the reaction vessel for use in the reaction to separate the gas into gaseous and liquid components and return some or all of the gaseous components to the contacting step for reuse as some or all of the heat removal solvent a partial condensation step; and the step of incinerating the liquid component and, when not all of the gaseous component is returned to the contacting step, incinerating the residue of the gaseous component.

Description

technical field [0001] The present invention relates to a process for the continuous preparation of cellulose ethers such as alkylcelluloses, hydroxyalkylcelluloses and hydroxyalkylalkylcelluloses. Background technique [0002] Cellulose ethers have been used in various fields such as industrial fields, food fields, and medical fields. The reaction slurry usually contains neutral salt, methanol, alkylene glycol and other by-products produced during the preparation of cellulose ether. Some of these by-products hinder the properties of cellulose ethers and are substances harmful to human health. Therefore, it is necessary to remove the by-products. [0003] When preparing cellulose ether, it is difficult to suppress one or more side reactions of etherification reagents, and after the etherification reaction is completed, it is also necessary to remove a large amount of neutral salts and alkalis derived from alkalinization of cellulose. Salt. The side reactions in the ether...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C08B11/193C08B11/02C08B11/06C08B1/08
CPCC08H8/00Y02P20/582C08B1/08C08B11/02C08B11/08
Inventor 山本厚黑谷伸一米持敦彦成田光男
Owner SHIN ETSU CHEM IND CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap