A method for continuous crystallization of vitamin C

Abstract

The invention discloses a method for continuous crystallization of vitamin C. It includes the following steps: pump the ion-exchanged vitamin C aqueous solution into the first-stage crystallizer for vacuum evaporation and crystallization, and then continuously introduce the vitamin C evaporation concentrate produced in the first-stage crystallizer into the second-stage crystallizer for vacuum cooling Crystallization, after liquid-solid separation, crystal washing, centrifugation, and continuous discharge to obtain crude vitamin C crystals; after the crude vitamin C is dissolved in purified water, it is filtered and pumped into the third-stage crystallizer to realize continuous crystallization of high-quality vitamin C. After liquid-solid separation, crystal washing, centrifugation, and continuous discharge to obtain high-quality vitamin C crystals. The method adopted in the invention can realize the continuous crystallization of vitamin C and obtain coarse, uniform and neat crystal grains, which can not only improve product quality, but also reduce production cost.

Description

technical field [0001] The invention relates to the technical field of vitamin production, in particular to a method for continuous crystallization of vitamin C. Background technique [0002] The vitamin C production process of the prior art is: obtain 2-keto- L-Sodium Gulonic Acid Fermentation Broth; the protein and other impurities in the fermented liquid are removed by ultrafiltration, and sodium ions are removed by cation exchange to become 2-keto-L-gulonic acid aqueous solution, which is then concentrated, cooled and crystallized, liquid-solid The crystal 2-keto-L-gulonic acid intermediate was obtained by separation; using sulfuric acid as a catalyst, 2-keto-L-gulonic acid was subjected to methyl esterification reaction in methanol solution system to generate 2-keto-L-gulonic acid methyl Add a certain amount of sodium bicarbonate to carry out alkali conversion reaction to generate vitamin C sodium salt solution. After cooling and sedimentation, liquid-solid separation ...

AI Technical Summary

Problems solved by technology

The cooling crystallization and liquid-solid separation of crude vitamin C and the cooling crystallization and liquid-solid separation of high-quality vitamin C have relatively low requirements for equipment. The saturated vitamin C supersaturated solution causes the obtained vitamin C crystal particles to be fine and poor in crystal form, which cannot further improve the quality and yield of the product