将5次固态交换制备的CO2+-NaX于500℃焙烧6h,再进行一次固态交换制备高稳定性催化剂,ICP 分析表明其CO2+含量为9.13%,高于5次固态交换CO2+-NaX的平衡CO2+含量(8.42%).采用XRD,N2吸附-脱附对催化剂进行表征,结果表明,分子筛离子交换后其骨架结构没有受到破坏,然而随交换进入分子筛CO2+含量增多,其有序性下降越明显.通过正交实验对该催化剂催化苯乙烯环氧化进行考察,确定了优化的反应条件:苯乙烯用量6mL,催化剂1.0g,溶剂48mL,反应温度80℃,反应时间6h.在此条件下,环氧苯乙烷平均收率为39.5%.采用该法制备催化剂其活性能够进一步提高,且重复使用活性保持不变.%Highly stable Co2+-NaX catalyst was prepared from Co2+-NaX, which was prepared by five times of solid-state ion-exchange, calcination at 500 ℃ for 6 h and then another solid-state ion-exchange. ICP results showed that mass fraction of Co2+ in the highly stable Co2+-NaX catalyst was 9.13％, which exceeded equilibrium Co2+ mass fraction in Co2+-NaX prepared by five times of solid-state ion-exchange (8.42％) . The catalysts were characterized by XRD and N2 adsorptiondesorption. The results indicated that the framework of NaX was not destroyed after Co2+ exchange,whereas the ordering of NaX decreased with increasing content of Co2+ into the zeolite. The optimal conditions were obtained by orthogonal experiments as: styrene 6 mL, catalyst 1.0 g, solvent 48 mL,reaction temperature 80 ℃ and reaction time 6 h. Under such conditions, the average yield of styrene oxide was 39.5％. The catalyst prepared by this method showed higher catalytic activity than Co2+-NaX prepared only by five times of solid-state ion-exchange, and the activity was stable after reuse.
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