A kind of method for preparing glucosamine hydrochloride

Abstract

A method for preparing glucosamine hydrochloride is characterized in that the following steps are adopted: 1) chitin is processed by gas explosion expansion method: the chitin raw material is packed in an air explosion expansion tank, and the gas explosion expansion medium is injected into the gas explosion expansion medium. Use one of water vapor, water, ammonia water, and ethanol; instantly release the pressure in the gas explosion expansion tank, and spray the chitin raw material into the normal pressure container to obtain the chitin concentrate; 2) hydrochloric acid hydrolysis; 3 ) decolorization; 4) filtration; 5) concentrated crystallization; 6) secondary crystallization. Compared with the prior art, the present invention has the following advantages: 1) the chitin pretreated by the gas explosion puffing method is used as raw material, which has higher chemical activity and can obtain higher product yield; 2) in the hydrolysis process , almost no "coking" phenomenon; 3) GAH is extracted once in the process, and the preparation of GAH becomes simple; 4) Hydrochloric acid can be recycled to realize clean production of GAH.

Description

technical field [0001] The invention relates to a method for preparing glucosamine hydrochloride, in particular to a method for preparing glucosamine hydrochloride using chitin treated by an air explosion expansion method as a raw material. Background technique [0002] Glucosamine hydrochloride, also known as D-glucosaminehydrochloride (GAH for short), the chemical name is 2-amino-2-deoxy-β-D-glucose hydrochloride, and the chemical formula is C 6 h 14 o 5 NCl, with a relative molecular mass of 215.63, is a white crystalline powder, easily soluble in water but insoluble in ethanol. GAH is a biological agent, which has important physiological significance in the human body: it participates in liver and kidney detoxification, has anti-inflammatory and liver-protecting effects; it can be used to treat rheumatoid arthritis and gastric ulcer disease; if used in conjunction with antibiotics, it can promote antibiotics Absorption in the blood reduces side effects and can inhibit...

AI Technical Summary

Problems solved by technology

Because chitin extracted from shrimp and crab shells has a dense crystal structure, chitin is usually pretreated by crushing and soaking in dilute hydrochloric acid. Even if such a pretreatment method is adopted, it is still difficult to change its dense crystal structure and It is difficult to make it chemically modified. Therefore, the hydrolysis reaction has to adopt higher concentration of hydrochloric acid, higher reaction temperature, and longer reaction time, thus producing a series of disadvantages: 1) while degrading and deacetylating, accelerating 2) Severe "coking" phenomenon occurs, which increases equipment wear; 3) GAH needs to be further extracted from the "mother liquor" after the hydrolysis reaction, which makes the production process more complicated; 4) Hydrochloric acid is difficult to recover , not only wasting raw materials, but also increasing pollutant emissions

Nevertheless, the yield of the traditional preparation GAH process has not exceeded 70%, and there are the above-mentioned shortcomings