Catalytic Synthesis Of Allantoin

Allantoin is one of important products of industry of fine chemicals, used in many domains, such as medicine,agriculture and biological engineering. So its chemical synthesis is paid much attention. Now condensating glyoxylic acid and oxiding glyoxal are the most extensive in the means of allantoin's preparation. The paper researchs the two kind means and searchs the best reaction conditions. At the same time, the rate of production is enhanced.Condensating glyoxylic acid consists of the ways of liquid inorganic acid, inorganic heteropolyacid and solid superacid, in accordance with the catalyst used in the reaction. The paper researchs the catalytic mechanism and property and searchs the best reaction conditions. The rate of production is also enhanced. The rate of production used violet acid of sulfuric acid and phosphoric acid as catalyst is 75%. The pilot reaction is made good. And a new kind of catalyst, phosphato-molybdic acid, is found.Oxiding glyoxal consists of many ways, in accordance with the oxidant used in the reaction. The paper chooses hydrogen peroxide, and researchs the influent factors of the reaction.The determination of prepared allantoin consists of purity, melting point, drying weight loss and combustion residue. The result of determination meets the national and foreign standards and codes The infra-red spectra and nuclear magnetic resonance of the prepared allantoin are nearly uniformity. It proves that the prepared product is allantoin.