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Different solid base catalysts used for the polymerization of glycerol were prepared by impregnation. Catalyst type and the preparation conditions were optimized on the base of polymerization degree. Results showed: the best catalyst was KF/Al2O3, and optimal condition for catalyst preparation was as follows: loading of 40% KF, calcinations temperature 600°C. The polymerization degree of 5.92 was obtained under the following reaction condition: the amount of catalyst 11.62,reaction temperature 250°C, reaction time 4 h.

WO3/ZrO2 solid superacid catalysts were prepared by coprecipitation and impregnation, then were characterized by XRD, N2 adsorption-desorption, Hammett indicator and pyridine chemisorption IR. The acid strength, acid type, acid volume, etc were compared under the different preparation conditions. The results indicated that the catalyst prepared by coprecipitation had stronger acid strength than the catalyst prepared by impregnation. The samples prepared by impregnation had more Lewis acid sites. With the increasing of the W/Zr ratio, the acid strength tended to increase at first and then decrease, and the catalyst with 10% WO3 loading amount had the strongest acidity. The higher the calcination temperature, the less the Lewis acid sites.