Preparation Of Epichlorohydrin With Glycerol

The content of this study as follows:This experiment is divided into two steps: the chlorination of glycerol and the cyclization of dichloropropanol.The effect of different factors on chlorination of glycerol was investigated in a packed reactor. On the basis of the Box-Behnken design principle, a quadratic polynomial mathematical model for preparation of dichloropropanol with glycerol was obtained by using the three-level-three-factor response surface methodology, and the influences of the temperature, catalyst loading and flow velocity of glycerol on the yield of dichloropropanol were investigated by determining the yield of dichloropropanol as the response. The optimum condition for preparation of dichloropropanol with glycerol was obtained as follows: the reaction temperature was 106.31℃, the flow velocity of glycerol was 0.6 mL/min and catalyst loading was 7.91 % (w/w). The yield of the dichloropropanol had reached to 88.04 % under the optimal conditions. The influences of the temperature, catalyst loading and flow velocity of glycerol were also optimized with orthogonal design. The results showed that temperature had the largest effect, the second was catalyst loading, and flow velocity of glycerol had the least effect.This step investigated the influence of different factors on cyclization of dichloropropanol. The influences of the mole ratio of dichloropropanol to NaOH,reaction temperature and reaction time on the yield of dichloropropanol were investigated by using the same three-level-three-factor response surface methodology.The experimental results show that the optimum conditions for cyclization of dichloropropanol is as follows: mole ratio of NaOH to dichloropropanol is 1.2:1 and reaction time is 98.15 s at 75℃.The yield of the epichlorohydrin had reached to 88.04 % under the optimal conditions. The orthogonal design results showed that the mole ratio of dichloropropanol to NaOH had the largest effect, the second was reaction time, and reaction temperature had the least effect.The kinetic model of the reaction was established and proved, and the kinetic parameters of the reaction were obtained.The results showed that the cyclization of dichloropropanol is a simple second order reaction, and the activation energies of 1,3-dichloropropanol and 1,2-dichloropropanolare 93.5 kJ/mol and 971.9 kJ/mol.