Co2＋离子交换NaX分子筛催化苯乙烯环氧化.pdfVIP

学兔兔 化 工 进 展 2011年第30卷第3期 CHEMICAL INDUSTRY AND ENGINEERING PROGRESS ·557· Co2+离子交换NaX分子筛催化苯乙烯环氧化 张 旭，许茂东，李兴扬，李 芳 (安徽工程大学生物与化学工程学院，安徽 芜湖 241000) 摘 要：将5次固态交换制备的Co2+-NaX于500℃焙烧6 h，再进行一次固态交换制备高稳定性催化剂，ICP 分析表明其co 含量为9．13％，高于5次固态交换Co2+一NaX的平衡 Coz+含量 (8．42％o采用XRD、N2吸附一 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 co 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6 mL，催化剂1．0 g，溶剂48 mL，反应温度80℃，反应时间6 h。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。 关键词：离子交换；X型分子筛；苯乙烯；催化环氧化；环氧苯乙烷 中图分类号：TQ 241．2 1 文献标志码：A 文章编号：1000—6613(2011)03—0557—05 Epoxidation of styrene catalyzed by Co ．exchanged NaX zeolite ZHANGXu。XUMaodong．LIXingyang，LIFang (School of Biological and Chemical Engineering，Anhui Polytechnic University，Wuhu 241000，Anhui，China) Abstract：Highly stable Co 一NaX catalyst was prepared from Co 一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 Co in the highly stable Co2+_NaX catalyst was 9．13％，which exceeded equilibrium Co mass fraction in Co2+_NaX prepared by five times of solid—state ion—exchange(8．42％)．The catalysts were char acterized by XRD and N2 adsorption— desorption．The results indicated that the framework of NaX was not destroyed after Co exchange， whereas the ordering of NaX decreased with increasing content of Co into the zeolite．The optimal conditions were obtmned by o~hogonal experiments as：styrene 6 mL，catalyst 1．0 g，solvent 48 mL， reaction temperature 80℃ and reaction t