Zr-FSM-16中孔分子筛的合成及其对苯羟基化的催化性能  

Synthesis of Zr-FSM-16 Mesoporous Zeolite and Its Catalytic Performance for Hydroxylation of Benzene

作　　者：江国东[1] 廖世军[1] 简弃非[1] 

机构地区：[1]华南理工大学应用化学系,广东广州510640

出　　处：《催化学报》2005年第2期123-126,共4页

基　　金：广东省自然科学基金资助项目 (0 2 0 863 ) ;广东省自然科学基金重点资助项目 (0 10 2 3 6) .

摘　　要：以十六烷基三甲基溴化铵 (CTMAB)为模板剂 ,合成出Zr FSM 16中孔分子筛 ,并采用XRD ,IR和BET等对分子筛进行了表征 .考察了Zr掺杂量和 pH值等因素对分子筛结构的影响 ,并考察了合成出的Zr FSM 16分子筛对苯羟基化反应的催化性能 .结果表明 ,Zr能有效地嵌入FSM 16的骨架之中 ,但Zr的嵌入对分子筛中孔结构的形成具有一定的不利影响 ,随着Zr嵌入量的增加 ,分子筛的长程有序度会下降 ;pH值对分子筛中孔结构的形成也具有十分显著的影响 ,在n(Si) /n(Zr) =4 0的条件下 ,pH <12 5时 ,有序度随着pH值的升高而升高 ,pH >12 5时则相反 .一般在n(Si) /n(Zr) >4 0时 ,催化剂均能保持较好的六方晶体结构和较大的比表面积 ;n(Si) /n(Zr) <2 0时 ,则较难形成中孔结构 .Zr FSM 16对于苯的羟基化反应具有良好的催化性能 ,催化活性和选择性均随Zr嵌入量的增加而升高 ,n(Si) /n(Zr) =4 0时 ,苯酚的选择性可达 6 5 %以上 .The Zr-FSM-16 mesoporous zeolite was synthesized by using cetyltrimethyl ammonium bromide (CTMAB) as a template, and the samples were characterized by XRD, IR and N-2 adsorption. Effects of some synthetic factors, such as the zirconium amount and pH value, on the formation of meso-structure were investigated. The catalytic performance of Zr-FSM-16 for hydroxylation of benzene was studied. The zirconium could be incorporated into the frame of FSM-16 zeolite, but it exerted a negative effect to the meso-structure of Zr-FSM-16 zeolite, the long-range order of Zr-FSM-16 decreased with the increase of zirconium amount. The pH value affected the formation of Zr-FSM-16 zeolite remarkably. At n (Si)/n (Zr) = 40, the order of Zr-FSM-16 was enhanced with the increase of pH value when pH < 12.5, and a reverse result was obtained when pH > 12.5. The Zr-FSM-16 zeolite showed higher activity for hydroxylation of benzene, and both the activity and selectivity increased with the increase of zirconium amount. The selectivity for phenol of Zr-FSM-16 with n (Si)/n (Zr) = 40 could reach 65%. Generally, when n (Si) In (Zr) > 40, the catalyst possessed good mesoporous structure and high surface area, and it was difficult to form meso-structure when n (Si)/n (Zr) < 40. The variation of structure and surface area verified the incorporation of Zr into the framework of FSM-16 zeolite.

关 键 词：锆 FSM-16 中孔分子筛 合成 苯 羟基化 

分 类 号：O643[理学—物理化学]