Synthesis Of Epichlorohydrin From Glycerol

At present,the main methods to produce epichlorohydrin chlorination are through allyl chloride route at high temperature or allyl alcohol route.But the two methods both use propylene as raw materials,which cost a large amount of non-renewable petrochemical resources and produce a large number of wastewater and waste residue.In this paper,we use glycerol as raw materials to synthesize 1,3-dichloro -2-propanol in tubular reactor under the conditions of circulation.The influence of different catalysts in the process of chlorination were researched,and on the basis, orthogonal experimental method was employed.The reaction temperature,the reaction time,the pressure and the amount of catalyst were used to find out the optimized conditions.The results were:1)The optimized catalyst was propionic acid.2)The optimized reaction conditions of initial chlorination were:reaction temperature 100℃,reaction time 1h,the amount of catalyst 3%(Mole ratio,to the amount of glycerol),reaction pressure 5atm.Under these conditions,the conversion of the glycerin was more than 68%.3)The optimized reaction conditions of further chlorination were as follows: reaction temperature 130℃,reaction time 1h,the amount of catalyst 1.5%,reaction pressure 5atm.Under these conditions,the conversion of the glycerin was more than 98%and the yield was more than 50%.Meanwhile,1,3-dichloro-2-propanol made by the author was cyclized.And the influence of CaCl₂ was studied,the results were as follows:1)Under the condition of the same amount of CaCl₂ and ECH,as the temperature decreases and reaction time increases,the concentration of ECH in solution become lower.2)Under the condition of the different amount of CaCl₂ and ECH,at the temperature of 75℃,as the Moore ratio and reaction time increase,the concentration of ECH become lower.