Traditional D-Glucosamine Hydrochloride production method usually adopts chitin acid hydrolysis method, as, the preparation method process steps of the glucosamine hydrochloride that the patent No. is 01127784.X is: acid hydrolysis, filtration, concentration, purification, reconcentration, cooling, Filter, spray ethanol, pump out ethanol, and finally dry it. Although the amount of ethanol required for washing hydrochloric acid is reduced, the process route is long and complicated, and the purpose of low-cost production cannot be achieved, and the problem of pollution cannot be overcome. In addition, due to the use of a large amount of water in the reaction process, the operation is cumbersome, the energy consumption is high, and the amount of sewage discharge is large.
CN101125892A discloses a kind of production method of D-Glucosamine Hydrochloride, comprises the following steps:
1) Acid hydrolysis: put hydrochloric acid and chitin into the reactor at a ratio of 5:1 at a temperature below 50°C. After feeding, control the temperature of the reactor at 85°C to 88°C and keep it warm for 3 hours to obtain the crude material liquid ;
2) Decolorization and pressure filtration: add activated carbon to the crude product liquid for decolorization, cool down to 50°C, and perform pressure filtration to obtain the filtrate;
3) Purification: Purify the filtrate through a secondary reverse osmosis system to obtain a purified filtrate;
4) Concentration and crystallization: the purified filtrate is vacuum concentrated and crystallized at a pressure of -0.09 to -0.1Mpa and a temperature of 50 to 55°C, and the material is cooled and discharged when crystals appear;
5) washing the crystal first, and then drying it until the water content is below 0.5%;
6) Crushing, sieving and packaging.
In the production process of the product of the present invention, the ratio of hydrochloric acid to chitin is adjusted to be 5:1, the temperature is controlled at 85°C to 88°C, and the time is controlled at 3 hours. There is no need to cool and crystallize, and directly add activated carbon to the reaction vessel for decolorization. , saves the separation and water dissolution of crude product crystals, saving time and water. The crude feed liquid is not directly concentrated after being filtered by a filter press, but is filtered through an ultrafiltration system to remove grease and inorganic salts, which solves the problems of clarity and light transmittance of the finished product, and improves product quality. The concentrated crystals are washed, dried, crushed and sieved, packaged and shipped.
