New technique for extracting D-glucosamine hydrochloride

Abstract

A new technique for extracting D-glucosamine hydrochloride comprises steps of hydrochloric acid hydrolyzation, devitrification, filtration, re-devitrification and re-filtration after concentrating thefiltrate, semi-product decoloration, destaining solution re-crystallization and refinery, and the like. The technique adopts full closed type closed loop cycle operation, discharges no waste liquid or acid mist, remarkably relieves direct harm of hydrochloric acid waste gas on operating workers, and is clean and environment-friendly. During hydrolyzation, acid solution is heated, afterwards chitosan is added in succession, the hydrolyzation adopts sectional heating method, adds a low temperature reaction stage, effectively reduces coking, and improves product yield. In the reaction process, N2 protection is adopted, the moisture during hydrolyzation is subject to steam stripping, thus avoiding incomplete reaction of hydrolyzation and low yield due to reduced hydrochloric acid concentration caused by high water content in the raw materials. N2 protection facilitates the reactions to be smooth and fast and reduces generation rate of side reaction, thus the quality of the product is morepure.

Description

technical field [0001] The invention relates to a method for preparing D-glucosamine hydrochloride, in particular to a new process for extracting D-glucosamine hydrochloride from natural chitin. Background technique [0002] D-glucosamine hydrochloride, also known as glucosamine hydrochloride, is extracted from natural chitin and is a marine biological preparation. Its scientific name is 2-amino-2-deoxy-β-glucopyranose hydrochloride. It is a stable compound of glucosamine. It is a pharmaceutical intermediate with important application value. It has important physiological functions for the human body, participates in liver and kidney detoxification, plays an anti-inflammatory and liver-protecting role; stimulates the growth of bifidobacteria in the intestinal tract of infants; can promote the synthesis of mucopolysaccharides in the human body and improve joint slippery The viscosity of the liquid can improve the metabolism of articular cartilage, and has obvious anti-infla...

AI Technical Summary

Problems solved by technology

[0003] Its preparation process generally adopts processes such as hydrolysis, concentration, decolorization and crystallization. In the existing process, from the post of hydrolysis, concentration, decolorization and crystallization to the open storage tank, a large amount of unorganized waste hydrochloric acid gas is discharged into the operating environment. Equipment, operators and the environment have caused immeasurable pollution and corrosion

The concentrated material has a large amount of black acid after suction filtration. This part of the waste acid should be neutralized and discharged after passing the inspection. However, most manufacturers do not treat it due to cost issues and discharge it directly, which pollutes water resources.

Due to the hydrolysis, concentration, decolorization, and crystallization, after the discharge of the post, it will go to the next step after a long time of vacuum filtration (about 15 hours), which consumes a lot of electricity.

[0004] In the whole preparation process, the hydrolysis process is the key to the yield and quality of the product. In the existing process, the one-stop heating method of directly raising the temperature to the required temperature is generally adopted. After intense compounding and decomposition reactions, the semi-finished product If the color deepens, the quality of the product will be unstable, some products will be coked, the quality will be impure, and the product yield will be low

Images