Vitamin D separating, purifying and crystallizing method

Abstract

This invention involves the separating purification and crystallization method to vitamin D2, D3, D4. Dissolve the actinic oil of vitamin D in absorption solvent by weight ratio of 0.3-3, feed it into chromatography column which has installed alumina inside; Elute separating by elution solvents, collect by subsection, track the part of pure vitamin D with the folium analytical approach, until vitamin D is totally washed out; The pure vitamin D component that has been collected decompresses to remove solvents, put into the crystal solvent, when -5 to -10 deg. C, freeze and crystal, filter after 10-16 hours, vacuum getting dry vitamin D crystallisation. This invention improves accepting rate and purity, the craft is simple, lower costs and has reduced the environmental pollution.

Description

technical field [0001] The invention belongs to the field of photochemical synthesis of vitamin D, in particular to vitamin D 2 、D 3 、D 4 Methods of purification, separation and crystallization. Background technique [0002] Vitamin D is one of the important vitamins essential for human health, normal growth and reproduction of livestock and poultry. There are a lot of impurities such as tachysterol and photosterol and residual 7-dehydrocholesterol in the products of photochemical synthesis of vitamin D. These by-products Due to the similar structure and properties, it seriously affects the separation, purification and crystallization of vitamin D. Among them, tachysterol is also a toxic by-product, so it must be separated and removed. The classic method to remove these impurities is to adopt 3,5-dinitrobenzoyl chloride or butyryl chloride esterification crystallization separation and purification method. This method has a long process flow, high toxicity and a lot of thr...

AI Technical Summary

Problems solved by technology

Because it is a chemical separation method, there is a lot of loss of vitamin D, and there are incomplete esterification, so the yield is low

The chromatographic method uses benzene as a solvent, which is highly toxic.

The supercritical column chromatography described in Chinese patent 99108675.9 requires high pressure of 7.5-15Mpa, which requires high equipment safety, is difficult to industrialize, and requires expensive modified silica gel