钛硅分子筛催化乙烯一步法高效合成乙二醇OA

The microstructures of self-developed post-modified titanium silicon zeolite TS-1 with dual functions of epoxidation and hydration(EYH)and unmodified TS-1,which was used as the catalyst for the one-step synthesis of ethylene glycol(EG)from ethylene,were systematically characterized and compared by N2 adsorption-desorption,XRD,TEM and UV-Vis.The effects of reaction conditions including solvent type,reaction temperature,EYH amount,H2O2 amount and H2O2 feeding rate on the catalytic activity of EYH were also systematically investigated.The experimental results show that the EYH catalyst possesses abundant four-coordinated framework Ti active sites and intracrystalline hollow mesoporous structures,which can enhance the accessibility of active centers and significantly improve the catalytic activity.Under the reaction conditions of solvent B of 6.4 g,w(EYH)=5.9%,w(H2O2)=6.3%,feeding H2O2 0.02 g in 1 min,reaction temperature of 40℃,reaction time of 2 h and reaction pressure of 1 MPa,the EG content and selectivity are 9.9%(w)and 92.0%,respectively,the conversion and effective utilization of H2O2 are 97.8%and 96.3%,respectively,and the yield of EG and diethylene glycol reaches 94.1%.Furthermore,EYH still maintains high catalytic activity after repeated cycles and exhibits excellent stability.