Normal temperature crystallization method of glucuronolactone

Abstract

The invention provides a normal temperature crystallization method of glucuronolactone. The method comprises the following steps: adding an glacial acetic acid and an acetic oxide to obtain a reactant after carrying out enzymolysis and fermentation on oxidized starch; firstly, agitating the reactant at the rotating speed of 30-100 r / min at room temperature, and then agitating the reactant at a constant speed for 8-12 hours; continuing to agitate at the constant speed of 50-80 r / min for 48-52 hours, and then stewing for 4-6 hours; carrying out vacuum filtration after stewing, so as to obtain a glucuronolactone crude product; washing the glucuronolactone crude product by using absolute ethyl alcohol, and then drying into constant weight. The defects that equipment in freezing crystallization is high in investment, high in energy consumption, and difficult to separate crystal are avoided by normal temperature agitating crystallization. By adopting the normal temperature agitating crystallization method provided by the invention, (1) undercooled melt is not needed again, so that an energy source consumed for producing the undercooled melt is saved; (2) soluble or insoluble impurities in the glucuronolactone are fully utilized, so that formation and growth of glucuronolactone crystal are facilitated by taking the soluble or insoluble impurities as crystal nucleus.

Description

technical field [0001] The invention belongs to the field of production of pharmaceutical raw materials, and in particular relates to a crystallization method of glucuronolactone at room temperature. Background technique [0002] Glucuronolactone is a good medicine for treating hepatitis, liver cirrhosis and connective tissue diseases. my country and Japan are the main producing countries of glucuronolactone. In recent years, due to the adjustment of Japan's industrial structure, my country has become the world's largest producer of glucose In aldolactone-producing countries, its sales are increasing at an annual rate of 20%. [0003] Since the invention of the glucuronolactone nitric acid oxidation process in the 1930s, the nitric acid oxidation process has been used in China to produce glucuronolactone. The biggest disadvantage of this process is that a large amount of nitrogen oxides and waste nitric acid are produced during the production process. cause serious pollution...

AI Technical Summary

Problems solved by technology

[0007] There are few studies on the crystallization process of glucuronolactone, and most of the industry adopts the freezing crystallization process. The biggest disadvantage of this process is: long crystallization time, high energy consumption, and very difficult product separation.

In order to overcome the shortcomings of the traditional process, Yuan Hua et al. adopted the three-time water-carrying process to obtain supersaturated glucuronolactone, which laid the foundation for crystallization at room temperature (25°C). However, this process still has high viscosity and crystallization Difficult separation and complex components, difficult to crystallize and low purity crystallization