Salen Mn(III)/MCM-48 catalyst was prepared and characterized by FT-IR,XRD,UV-Vis,and GC.The catalyst was evaluated by the epoxidation of styrene;remarkable activity and enantioselectivity were received.
High titanium loading MCM-41 was prepared via the novel post-grafting method by impregnating calcined MCM-41 into the Ti-Si sol.In comparison with the conventional direct synthesis and the impregnation method,the regu...High titanium loading MCM-41 was prepared via the novel post-grafting method by impregnating calcined MCM-41 into the Ti-Si sol.In comparison with the conventional direct synthesis and the impregnation method,the regular mesostructure was preserved and the four-coordinated titanium was evenly dispersed on the inner surface of MCM-41 through the present strategy.The product was characterized by XRD and UV-vis.The as-synthesized catalysts showed remarkable activities in the epoxidation of cyclohexene.The sample with Si/Ti = 10 revealed highest conversion and selectivity.展开更多
文摘采用溶胶-凝胶法在导电载玻片上制备均匀透明的纳米TiO2薄膜,并以此薄膜作为基体电极,在浓度为0.50 mol/L的H2SO4溶液中用恒电位法制备了TiO2-磷钨酸修饰电极,用SEM分析了不同薄膜的结构,并对其电阻率,电化学行为与光电特性进行了初步研究.实验结果表明,制备TiO2-H3PW12O40复合膜的最优化合成条件为:5.0×10-3mol/L磷钨酸(H3PW12O40)+5.0×10-3mol/L吡咯(PY)+0.5 mol/LH2SO4的混合溶液中于1.4 V恒电压下电沉积60 m in.
文摘Salen Mn(III)/MCM-48 catalyst was prepared and characterized by FT-IR,XRD,UV-Vis,and GC.The catalyst was evaluated by the epoxidation of styrene;remarkable activity and enantioselectivity were received.
文摘High titanium loading MCM-41 was prepared via the novel post-grafting method by impregnating calcined MCM-41 into the Ti-Si sol.In comparison with the conventional direct synthesis and the impregnation method,the regular mesostructure was preserved and the four-coordinated titanium was evenly dispersed on the inner surface of MCM-41 through the present strategy.The product was characterized by XRD and UV-vis.The as-synthesized catalysts showed remarkable activities in the epoxidation of cyclohexene.The sample with Si/Ti = 10 revealed highest conversion and selectivity.
