Method for continuous crystallisation of vitamin C

Abstract

The invention discloses a vitamin-C continuous crystallization method, including the following steps: a vitamin-C aqueous solution after ion-exchange is pumped into a first-stage crystallizing device for crystallization by vacuum evaporation; then the vitamin-C evaporated concentrated solution generated in the first-stage crystallizing device is continuously guided into a second-stage crystallizing device for crystallization by vacuum cooling; after the liquid and solid are separated, the crystals are washed and processed by centrifugation and then are continuously discharged to obtain the crude vitamin-C crystals; the crude vitamin-C crystals are dissolved by purified water and then pumped into a third-stage crystallizing device through a filter pump so as to realize the continuous crystallization of refined vitamin-C; after the liquid and solid are separated, the crystals are washed and processed by centrifugation and then are continuously discharged to obtain the refined vitamin-C crystals. The method adopted by the invention can realize the continuous crystallization of vitamin-C and obtain the large, even and well-shaped grains, which not only can enhance the quality, but also can reduce the manufacturing 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