Abstract:Solid superbases Rb2O/γ-Al2O3were prepared from rubidium salts separated from salt brine. Sucrose was used as the template, Rb2CO3 (prepared from RbCl) and Al(NO3)3 as the raw materials, we prepared Rb2O/γ-Al2O3 successfully by using in-situ method. In impregnation method, we first used sucrose as the template, Al (NO3)3 and Al[CH(CH3)2]3 as aluminum sources, respectively to prepare γ-Al2O3,and then a series of Rb2O/γ-Al2O3 with different rubidium contents through the impregnation of RbNO3 (prepared from RbCl). The base strength of Rb2O/γ-Al2O3 both can reach 26.5 or more, belonging to superbase prepared through the two methods by controlling the conditions. The prepared Rb2O/γ-Al2O3 solid superbases were used to simulate interesterification in the process of producing biodiesel by catalyzing triglycerides acetate and methanol. The optimum reaction conditions were as follows: the ratio of alcohol to ester was 8∶1, the reaction temperature was 338 K, the reaction time was 4 h, and the amount of catalyst is 6.0% of the weight of ester. Under those conditions, the productivity of methyl acetate was up to 98%.