The Technology Research Of Synthetize Dihydroxyacetone

Dihydroxyacetone (DHA) is widely used as the intermediates of pesticides and pharmaceutical, but also can be used as a additive in cosmetics , you can also add in the feed as the clenbuterol, the water purification, the preservative of food,it has a wide range of applications. DHA as a naturally occurring simple sugars, can also be biodegradabled, It has no harm to the environment and humanAt present, DHA is produced by means of microorganism fermentation at home. the advantages of this method is the conditions of moderate, high specificity, but low product concentration, resulting in the subsequent process of purificating complex and highly difficult to preparat production equipment, production costs increase significantly ,also resulted environmental pollution. Producting DHA by formose reaction has cheap chemical raw materials and simple conditions. However, the selectivity was rather low,because of the similarity of the reaction product, resulting in the subsequent process of purificating complex ,in foreign countries these problems have been resolved and entered the pilot scale test,but in our country has not obtained any substantial progress. In this paper, DHA obtaned by formose reaction and been characterized, Researching the synthetize condition of catalyzer and product preliminaty, Laying a good foundation for futher study of the product.Main parts of Experiment: primary, research the definite process of producing benzothiazole via hydrocarbonylation which use hydrogen peroxide and 2-Mercaptobenzothiazole, optimizing the synthetic technology in four areas:concentration of reactants ,reaction temperature, reaction time, acidification time,the ylide can achieve to 80% .Secondly, research the definite process of producing 3-ethylbenzothiazolium bromide by Bromoethane and benzothiazole , optimizing the synthetic technology in three areas: the mole ratio of raw mater ,reaction temperature, reaction time, According to the target product in different polarity solvents have different solubility presenting a new method to purificat it . Thirdly, under a nitrogen atmosphere, further studied the process of paraformaldehyde via self-condensation to give DHA in the anhydrous solvent , optimizing the synthetic technology in three areas: ,reaction temperature, reaction time, promoter volume, Through first esterificating the target product ,then hydrolysis,separation,purification ,the ylide of reaction from17% by literature increased to 37%.