两亲性Ti-V-β沸石的制备及其相界面催化反应性能的研究 |
Amphiphilic Ti-V-β Zeolites: Preparation and Phase-boundary Catalysis |
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摘要: 采用三甲基氯硅烷(TMS)和正十八烷基三氯硅烷(OTS)对Ti-V-β沸石样品进行表面修饰,制备出了两亲性TMS-Ti-V-β和OTS-Ti-V-β沸石,通过XRD,FTIR,UV-Vis,SEM和低温氮气吸附-脱附等手段对样品进行了表征。同改性前样品相比,两亲性Ti-V-β沸石骨架未遭破坏,只是晶貌发生了一些改变。其BET比表面积和BJH孔容均稍有下降(Ti-V-β为428 m2·g-1和0.54 cm3·g-1, TMS-Ti-V-β为382 m2·g-1和0.40 cm3·g-1, OTS-Ti-V-β为290 m2·g-1和0.28 cm3·g-1)。这类两亲性沸石能分布于水、油两相界面处,在不加共溶剂及静置的反应条件下,对环己烯水化的相界面反应表现出优良的催化活性( 环己烯的水合率和环己醇的选择性分别为: Ti-V-β 0.61%和76%、OTS-Ti-V-β 2.01%和90%、TMS-Ti-V-β 7.35%和95%)。可以看出,三甲基氯硅烷改性后的TMS-Ti-V-β沸石在相界面催化反应中,具有比改性前高得多的活性。 |
关键词: 两亲性沸石 制备 相界面催化 |
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Abstract: Amphiphilic TMS-Ti-V-β and OTS-Ti-V-β zeolites were prepared by modifying Ti-V-β zeolites with trimethylchlorosilane and n-octadecyltrichlorosilane, respectively. All the samples were characterized by XRD, FTIR, UV-Vis, SEM, and low temperature N2 adsorption-desorption. Modified samples retained their original crystal structure, while their crystal morphology was somewhat changed. N2 adsorption indicates that these amphiphilic zeolites have a little smaller surface area and BJH volume of pores compared with their parent zeolites(BET surface area and BJH volume of pores of zeolites are 428 m2·g-1 and 0.54 cm3·g-1 for Ti-V-β, 382 m2·g-1 and 0.40 cm3·g-1 for TMS-Ti-V-β, and 290 m2·g-1 and 0.28 cm3·g-1 for OTS-Ti-V-β, respectively). These amphiphilic Ti-V-β zeolites can be distributed at the water-organic phase boundary. They both show good catalytic performance in the phase-boundary reactions of cyclohexene hydration without co-solvents and stirring(the hydration yield of cyclohexene and the selectivity of cycloheanol are 0.61% and 76% for Ti-V-β, 2.01% and 90% for OTS-Ti-V-β, and 7.35% and 95% for TMS-Ti-V-β, respectively). The experimental results indicate that the Ti-V-β zeolite modified with trimethylchlomsilane, TMS-Ti-V-β, has much higher catalytic activity than its parent Ti-V-β zeolite in the phase-boundary catalysis. |
Keywords: amphiphilic zeolite preparation phase-boundary catalysis |
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摘要点击次数: 1242 |
全文下载次数: 1983 |
肖质文,李艳凤,何 震,喻 铃,何红运.两亲性Ti-V-β沸石的制备及其相界面催化反应性能的研究[J].无机化学学报,2008,24(11):1880-1884. |
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