摘要
以分子筛MSU-1为载体,La、Ce、Cu和K为改性剂,制备了一系列改性的VO_x/MSU-1催化剂,并系统地评价了催化剂的反应活性。采用XRD、H_2-TPR及NH_3-TPD对改性催化剂La1.0V10.0/MSU-1[w(VO_x)=10.0%,w(La2O_3)=1.0%]进行了表征,并考察了最佳反应条件。结果显示:稀土元素La、Ce的加入能提高催化剂的活性,La元素的加入提高了载体MSU-1上活性组分VO_x的分散度,同时也改善了催化剂表面的酸碱性,更加有利于异丁烷氧化脱氢反应的进行。在最佳反应条件下(温度853 K,体积空速4 800 h^(-1),常压,CO_2与异丁烷体积比为3∶1),催化剂La1.0V10.0/MSU-1上异丁烷的转化率为63.6%,异丁烯的产率为52.3%。稳定性实验结果表明:8 h循环后,催化剂V10.0/MSU-1[w(VO_x)=10.0%]上异丁烷转化率降为16.5%,而La1.0V10.0/MSU-1上为28.8%,说明La改性的VO_x/MSU-1催化剂具有更好的稳定性。
For further improving the catalytic performance of VO_x/MSU-1 in the reaction of oxidative dehydrogenation of isobutane to isobutene with CO_2,in this paper,a series of modified VO_x/MSU-1catalysts were prepared using MSU-1 as the supports and La、Ce、Cu and K as the performance modifier,and then their reaction activity were evaluated systematically. Meanwhile,La1. 0V10. 0/MSU-1[w（VO_x） = 10. 0%,w（La2O_3） = 1. 0% ]was characterized by XRD,H_2-TPR and NH_3-TPD methods and the reaction conditions were investigated. The results showed that La addition could improve not only the dispersion of VO_xspecies,active components,over MSU-1 support but also the acid-base properties of catalysts surface,which was favorable to the oxidative dehydrogenation of isobutane. Under the optimal reaciton conditions（temperature was 853 K; gas hourly space velocity was 4 800 h^（-1）;pressures was atmospheric; volume ratio of CO_2 and isobutane was 3： 1）,isobutane conversion was63. 6% and isobutene yield was 52. 3% using La1. 0V10. 0/MSU-1 as the catalyst. At last,it was demonstrated by the stability experiments of 8 h that La1. 0V10. 0/MSU-1 possessed higher catalytic stability than V10. 0/MSU-1 [w（VO_x） = 10. 0% ],isobutane conversion decreasing to 16. 5% over V10. 0/MSU-1 in contrast to 28. 8% over La1. 0V10. 0/MSU-1.
作者
孙果宋
黄世勇
黄青则
王秋萍
黄媚
张雪旺
王金淑
SUN Guo-song HUANG Shi-yong HUANG Qing-ze WANG Qiu-ping HUANG Mei ZHANG Xue-wang WANG Jin-shu(Guangxi Research Institute of Chemical Industry, Nanning 530006, Guangxi, China and Engineering, Beijing University of Technology, Beijing 100022, China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2017年第7期792-797,840,共7页
Fine Chemicals
基金
广西自然科学基金项目(2012GXNSFBA053033
2011GXNSFA018053)~~
