石油化工
2?12年第41卷第3期
PETROCHEMICAL TECHNOLOGY
超声辅助液相后合成Ti-SBA-15催化剂的表征
及其在丙烯环氧化中的性能
刘红梅,张明森,柯丽
(中国石化北京化工研究院,北京100013)
摘要」以全硅介孔分子筛SBA-15为载体,以钛酸四异丙酯为钬源,在超声辅助条件下采用液相后合成方法制备了Ti-SBA
15化剂,并借助XRD、N2吸附、TEM和UV-Vis等表征手段研究了催化剂的结构特性。以
过氧化氢异丙苯(CHP)为氧化
剂,考察了T-SBA-15催化剂在丙烯环氧化反应中的催化性能。实验结果表明,在超声波的空化作用下,Ti原子更易于进
SBA-15分子筛骨架中形成具有环氧化活性的四配位i物种,同时也有效减弱了后合成过程对SBA-15分子筛孔道结构的破
坏。与常规液相后合成方法相比,采用超声辅助液相后合成方法制备的Ti-SBA-15催化剂表现出更高的丙烯环氧化催化性
能,CIHP转化率达到94.8%,
环氧丙烷选择性达到96.5%,CHP的有效利用率达到91.5%a
[关键词]T-SBA-15催化剂:后合成;超声波;丙烯环氧化;环氧丙烷
[文章编号」1000-8144(2012)03-0265-07
中图分类号]TQ426.94
文献标识码]A
Characterization of TI-SBA-15 Catalysts Prepared by Ultrasonic Liquid-phase
Post-synthesis and Their Performance in Propylene Epoxidation
Liu Hongmei, Zhang Mingsen, Ke Li
(SINOPEC Beijing Rescarch Institute of Chemical Industry, Beiing 100013, China
bstract J TI-SBA-15 catalysts were prepared through a liquid-phase post-synthesis method
assisted by ultrasonic technique, with silica mesoporous molecular sieves SBA-15 as the support
and tetraisopropyl titanate as the Ti source. The TI-SB A-15 catalysts were characterized by means
of XRD, N adsorption, TEM and Uv-vis techniques. The catalytic performances of the TI-SBA-
15 catalysts in propylene epoxidation were investigated, using cumene hydroperoxide(CHP)as the
oxidant. It was indicated that, owing to ultrasonic cavitation, Ti atoms tend to be introduced into
the framework of SBA-15 molecular sieves and form tetrahedral-coordinated Ti species, which was
active in the epoxidation. Additionally, ultrasonic technique could effectively decrease the damage
of the pore structure of SBA-15 molecular sieves during the post-synthesis process. Compared with
the TI-SBA-15 catalyst obtained by a conventional liquid-phase post-synthesis, the one obtained
by the ultrasonic liquid-phase post-synthesis method exhibited high catalytic activity for propylene
epoxidation. The conversion of CHP, the selectivity to propylene oxide and the efticiency of CHP
could reach 94.8%0, 96.5%o and 91.5%o, respectively
L Keywords J TI-SBA-15 catalyst; post-synthesis; ultrasonic wave; propylene epoxidation
propylene oxide
1998年,Zhao等在酸性条件下,以三嵌段反应。但是由于SBA-15分子筛的孔壁较厚(一般
共聚物为模板剂、正硅酸乙酯为硅源,通过水热在2~7nm之间),进入分子筛骨架中的Ti物种只有
合成法成功制备了全硅介孔分子筛SBA-15。之后,一部分是接近分子筛表面的,另外一部分可能存在
人们为这种新材料开发了广泛的用途2。最近
[收稿日期]2011-09-27;「修改稿日期」201-11-15
有人尝试将T物种掺杂进SBA-15分子筛骨架中制『作者介」刘红梅(1976-)、女,辽宁省葫芦岛市人,博土
备Ti-SBA-15分子筛,用于催化大分子参与的氧化高级工程师,电话010-59202700,、电邮 liuhm. hihy(@sinope (om
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