无钙硫脲合成工艺的开发

Study on Synthesis Process of Calcium-free Thiourea

硫脲作为辅助材料,在医药、化工、橡胶等领域有多种用途。传统的硫脲生产工艺产生大量的废渣,不符合环保要求。采用尿素-劳森试剂法合成硫脲,该过程是无钙原料尿素和劳森试剂在氮气保护下,用四氢呋喃用作分散溶剂,直接合成硫脲,全程无废渣产生。采用正交试验法研究了反应温度、反应原料质量比和反应时间对硫脲产率的影响,并用红外光谱对产品结构进行了表征。

As an auxiliary material, thiourea has many uses in the fields of medicine, chemical industry and rubber,etc. The traditional production process of thiourea produces a large amount of waste residue and does not meet environmental protection requirements. In this study, the urea-Lawson reagent method was used to synthesize thiourea. The process was that the calcium-free raw material urea and Lawson’s reagent were used under nitrogen protection, and tetrahydrofuran was used as dispersing solvent to directly synthesize thiourea. The effect of reaction temperature, mass ratio of reaction materials and reaction time on the yield of thiourea was studied by orthogonal test. The structure of the product was characterized by infrared spectroscopy.