均相法合成丝光沸石/β沸石混晶材料的研究

以铝酸钠为铝源、硅溶胶为硅源、四乙基氢氧化胺为模板剂,通过调节β沸石晶化条件用均相法合成了丝光沸石／β沸石混晶材料。对混晶材料进行了XRD,SEM,NH3-TPD和BET表征,利用脉冲微反装置考察了在混晶材料上的甲苯烷基化反应性能。结果表明,混晶材料中存在的β沸石、丝光沸石不是呈纯粹的物理混合状态;混晶材料的孔道结构与机械混合物、β沸石、丝光沸石有所不同。由于混晶材料的高温脱附峰峰温比β沸石、机械混合物的峰温分别低6℃和10℃,而强酸酸量分别比β沸石、机械混合物大3％和7％,所以混晶材料与机械混合物、丝光沸石、β沸石相比,有较好的甲苯烷基化反应性能。以混晶材料催化的甲苯烷基化反应产物中的二甲苯收率较β沸石、机械混合物和丝光沸石为催化剂分别高27.2％,25.4％和13.6％。

Research of MOR/β Zeolite Co-crystalline Materials Synthesized in Homogeneous Phase

MOR/β zeolite co-crystalline materials had been synthesized by adjusting crystallizing conditions ofβ zeolite with NaAlO2, silica sol as sources of aluminum and silica respectively in homogeneous phase, and tetraethylammonium hydroxide (TEA+) as the template. MOR /β zeolite co-crystalline material was characterized by means of XRD,SEM,BET and NH3 -TPD. Reaction activity of MOR/βzeolite co-crystalline material in toluene alkylation was investigated in a impulsive micro reactor with toluene-methanol mixture as feedstock. MOR/βzeolite co-crystalline material consisted of two kinds of zeolite structure mordenite and β zeolite, which were different from their physical mixture. The pore structure of the MOR/βzeolite co-crystalline material could be distinguished from βzeolite,mordenite or their physical mixture. The peak of high temperature desorption of ammonia from MOR/β zeolite co-crystalline material shifted 6℃and 10℃to lower temperature and the strong acid amounts was 3% and 7% more thanβzeolite and the relevant physical mixture. Therefore co -crystalline MOR/βzeolite had better reactivity in toluene alkylation. The xylene yield on co - crystalline material was 27.2%,25.4% and 13.6% more thanβzeolite, the relevant physical mixture and mordenite, respectively.