Method for preparing D-glucosamine hydrochloride

Abstract

A method for preparing D-glucosamine hydrochloride includes the steps: placing chitin into a reaction tank, adding hydrochloric acid with stirring and heating the reaction tank for hydrolysis; uninterruptedly leading hydrochloric acid gas into hydrolysate in backflow hydrolysis; obtaining a solid crude product after cooling, precipitating and leaching the hydrolysate; adding deionized water and activated carbon into the crude product for decolorization prior to filtering so that faint yellow liquor is obtained; and the hydrochloric acid is recovered by means of vacuum concentration, obtaining a wet refined product by centrifugally dewatering concentrated materials and washing the wet refined product in alcohol prior to vacuum drying so that finished product crystals are obtained. Since the hydrochloric acid gas is led into the hydrolysate, the concentration of the hydrochloric acid of the hydrolysate is kept stable, a hydrolysis process is accelerated, and time for hydrolysis reaction is shortened. Besides, by the aid of increase of the hydrochloric acid concentration, the hydrolysis temperature can be decreased, and decomposition of the D-glucosamine hydrochloride is reduced. By the aid of the method, yield is increased, quality of the D-glucosamine hydrochloride is improved, and energy consumption and production cost are reduced.

Description

technical field [0001] The present invention relates to the preparation of glucose hydrochloride, specifically a method for preparing D-glucosamine hydrochloride. Background technique [0002] Glucosamine is a natural compound synthesized in the human body, which consists of a glucose and an amino group. Research shows that glucosamine plays a key role in helping to maintain and maintain lubrication in all joints of the body. Stimulates the synthesis of mucopolysaccharides in the body, which are the main chemical components of cartilage tissue. Glucosamine can also promote the entry of sulfur into cartilage tissue. [0003] At present, the traditional method of preparing glucosamine hydrochloride mainly adopts hydrochloric acid hydrolysis method for production. This method uses chitin as raw material, uses 2.5 times of raw material hydrochloric acid as degradation agent, and hydrolyzes at 90-95 ° C for 3.5-4.5 hours for a long time. In the entire production process, the h...

AI Technical Summary

Problems solved by technology

The concentration of hydrochloric acid is the basic driving force of the hydrolysis reaction. The higher the concentration, the faster the hydrolysis rate and the higher the degree of hydrolysis; while the increase of the hydrolysis temperature will increase the hydrolysis rate but at the same time cause the decomposition and destruction of the product, affecting the yield and quality; hydrolysis time Although lengthening can increase the degree of hydrolysis, it will also cause product decomposition and damage, which has a great impact on the yield; during hydrolysis, the concentration of hydrochloric acid in the hydrolyzate will gradually decrease due to the reaction, which will gradually affect the hydrolysis power.

[0004] The above-mentioned current traditional methods require high hydrolysis temperature (90-95°C) and long hydrolysis time (3.5-4.5 hours), resulting in long production cycle, high production cost, poor product quality and low yield. Severely limit the production and practical application of glucosamine hydrochloride products