Abstract A CoCe/ZSM-5 catalyst was prepared by ultrasonic-assisted impregnation for the catalytic combustion of toluene. To study the effect of Na+, a series of different Si/Al ZSM-5 zeolites and catalysts doped with Na were synthesized. The experimental results show that 0.71 wt% of Na+ can inhibit active growth, generate more active small crystal grains, and promote improvement of the catalytic activity by the grain boundary segregation block mechanism, the catalyst with 90 vol% conversion of toluene at 250 °C. Over 0.71 wt% of Na+ content will neutralize the acid centre of the catalyst, lowering the specific surface area of the catalyst and resulting in a gradual decrease in the catalytic activity.

中文翻译：

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Na+对CoCe/ZSM-5催化剂催化甲苯氧化性能的影响

摘要 采用超声辅助浸渍法制备了CoCe/ZSM-5催化剂用于甲苯催化燃烧。为了研究 Na+ 的影响，合成了一系列不同的 Si/Al ZSM-5 沸石和掺杂 Na 的催化剂。实验结果表明，0.71wt%的Na+可以抑制活性生长，生成更多活性小晶粒，通过晶界偏析阻断机制促进催化活性的提高，该催化剂在250℃下甲苯转化率为90vol% . Na+含量超过0.71wt%会中和催化剂的酸性中心，降低催化剂的比表面积，导致催化活性逐渐降低。