Synthesis technology of allantoin

Abstract

The invention discloses a synthesis technology of allantoin. The synthesis technology comprises the following steps: adding a glyoxylic acid water solution, urea, and a catalyst into a reactor, wherein the catalyst is a mixture composed of sulfamic acid and modified macroporous strongly-acidic styrene type cation resin according to a weight ratio of 1:5; carrying out reactions for 6-8 hours at a temperature of 60-63 DEG C, cooling the reaction mixture to the room temperature, filtering, carrying out recrystallization, washing, drying to obtain a finished product of allantoin; merging the filtrate and washing liquid, and processing the merged liquid to obtain the catalyst. The catalyst can be repeatedly used. According to the synthesis method, glyoxylic acid and urea are taken as the raw materials, sulfamic acid and modified macroporous strongly-acidic styrene type cation resin are taken as a composite catalyst, the allantoin is synthesized in one step; the macroporous cation resin is modified by metals and then mixed with sulfamic acid, the catalytic efficiency and repeated utilization rate of the catalyst are improved, the using amount of catalyst is reduced; the technical procedure is simple, no pollution is generated, and the synthesis technology is green and environment-friendly, has a good ecological effect, and generates good social benefits and economic benefits.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a synthesis process of allantoin. Background technique [0002] Allantoin is an important fine chemical product. It has physiological functions such as promoting epithelial cell growth, promoting wound healing and analgesia, softening keratin to maintain moisture, and stimulating biological growth. It is a drug with multiple functions. [0003] In medicine, allantoin is a drug with multiple functions. It can be used directly or as an additive. Allantoin can treat various skin diseases, such as psoriasis, dermatitis, dry skin, etc., and can promote skin Cell and tissue growth, rapid wound healing and pain relief can restore the skin or tissue to its original appearance, and can treat various ulcer diseases. In daily chemical industry, allantoin has no reports of irritation, photosensitivity, allergic reactions and other toxic and side effects in domestic and foreign app...

AI Technical Summary

Problems solved by technology

[0004] There are many ways to synthesize allantoin, including oxidation of uric acid and potassium permanganate, electrolytic reduction of oxalic acid, heating synthesis of urea and dichloroacetic acid, dissolution of calcium glyoxylate and hydrochloric acid, and direct condensation of glyoxylic acid and urea. It is legal, and it is most common to prepare allantoin by direct condensation of glyoxylic acid and urea. However, inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid are used as catalysts in the production, which has low yield, poor product quality, severe corrosion of equipment, complicated post-processing, serious Disadvantages such as polluting the environment