The synthesis of titanosilicalite has become a hotspot in the zeolite catalytic fields. In this paper, TS 1 zeolite samples were synthesized with tetrapropyl ammonium bromide as the template, with ammonia as the base ...The synthesis of titanosilicalite has become a hotspot in the zeolite catalytic fields. In this paper, TS 1 zeolite samples were synthesized with tetrapropyl ammonium bromide as the template, with ammonia as the base source and with the mixture of titanium tetrachloride and tetrabutyl orthotitanate as the titanium source. The TS 1 samples have excellent catalytic performance in epoxidation of propylene with aqueous hydrogen peroxide. The samples were characterized by XRD and IR. The introduction of chlorine decreases the association degree of titanium alkoxides and it may prevent preferential segregation of titanium and silicon.展开更多
1-Butylene epoxidation was catalyzed by microporous titanosilicate molecular sieves TS-1 synthesized by different methods and mesoporous titanosilicate molecular sieves Ti-HMS, using dilute hydrogen peroxide solution ...1-Butylene epoxidation was catalyzed by microporous titanosilicate molecular sieves TS-1 synthesized by different methods and mesoporous titanosilicate molecular sieves Ti-HMS, using dilute hydrogen peroxide solution as oxidant. The effect of the Si/Ti molar ratio of the catalyst TS-1 and Ti-HMS on their performance was investigated. Conventional TS-1 has smaller crystal size and higher activity than that of TS-1 synthesized by using TPABr as template or the method of gas-solid phase. The TS-1 synthesized by using TPABr as template exhibits the highest selectivity to 1, 2-epoxybutane （BO）. With the increase of Ti content in molecular sieves, the conversion of H2O2 increases. The catalytic activity of mesoporous Ti-HMS is lower than that of TS-1, and large amount of H2O2 is decomposed in 1-butylene epoxidation. The primary reason for low activity of Ti-HMS in 1-butylene epoxidation is that Ti-HMS has poorer hydrophobicity property than TS-1.展开更多
文摘The synthesis of titanosilicalite has become a hotspot in the zeolite catalytic fields. In this paper, TS 1 zeolite samples were synthesized with tetrapropyl ammonium bromide as the template, with ammonia as the base source and with the mixture of titanium tetrachloride and tetrabutyl orthotitanate as the titanium source. The TS 1 samples have excellent catalytic performance in epoxidation of propylene with aqueous hydrogen peroxide. The samples were characterized by XRD and IR. The introduction of chlorine decreases the association degree of titanium alkoxides and it may prevent preferential segregation of titanium and silicon.
文摘1-Butylene epoxidation was catalyzed by microporous titanosilicate molecular sieves TS-1 synthesized by different methods and mesoporous titanosilicate molecular sieves Ti-HMS, using dilute hydrogen peroxide solution as oxidant. The effect of the Si/Ti molar ratio of the catalyst TS-1 and Ti-HMS on their performance was investigated. Conventional TS-1 has smaller crystal size and higher activity than that of TS-1 synthesized by using TPABr as template or the method of gas-solid phase. The TS-1 synthesized by using TPABr as template exhibits the highest selectivity to 1, 2-epoxybutane （BO）. With the increase of Ti content in molecular sieves, the conversion of H2O2 increases. The catalytic activity of mesoporous Ti-HMS is lower than that of TS-1, and large amount of H2O2 is decomposed in 1-butylene epoxidation. The primary reason for low activity of Ti-HMS in 1-butylene epoxidation is that Ti-HMS has poorer hydrophobicity property than TS-1.
