摘要
沸石的改性是提高沸石择形催化性能的重要手段.因此,沸石的改性及改质剂作用机理的研究,受到人们的关注.本文采用浸渍法制得了非骨架含硼的催化剂,在沸石合成中引入硼得到了骨架含硼的催化剂,用高温硼酸水溶液处理制得了脱铝沸石中含硼的催化剂.用XRD,IR,TPD等对它们进行了表征.研究了硼在沸石中所处的状况及其对择形催化反应性能的影响.采用的探针反应为甲苯/乙醇烷基化反应.
ZSM-5 zeolite catalysts with non-skeletal boron were prepared by impregnation method, and B,Al-ZSM-5 zeolite catalysts with skeletal boron were prepared by adding H3BO3 during the synthesis process of ZSM-5 zeolite. Partial dealuminated ZSM-5 zeolite catalysts containing boron were prepared by treatment with H3BO3 solution at high temperature. The effect of boron states of zeolites modified by different methods on the catalytic activity was studied by XRD, TPD, ]R etc. The alkylation of toluene with ethanol was used as probe reaction. Due to the different boron states of zeolite catalysts, the results of alkylation were different. ZSM-5 zeolite catalysts with non-skeletal boron improved easily the para -selectivity. B,Al-ZSM-5 zeolite catalyst showed that the para -selectivity of alkylation increased with increasing the skeletal boron. The dealuminated ZSM-5 zeolite catalysts with boron treated by H3BO3 solution had higher para-selectivity than that treated by water vapor under the same treatment conditions.
基金
国家自然科学基金
