CO_(2)气氛下SiO_(2)改性TiO_(2)催化乙苯脱氢工艺研究

Dehydrogenation of ethylbenzene over SiO_(2) modified TiO_(2) catalyst in CO_(2)

采用溶胶-凝胶法制备TiO_(2)-SiO_(2)催化剂,研究SiO_(2)负载量对TiO_(2)-SiO_(2)催化剂活性、稳定性的影响。考察反应温度、乙苯空速及催化剂粒径对乙苯脱氢制苯乙烯工艺的影响,并对催化剂进行BET及SEM表征。结果表明,TiO_(2)-SiO_(2)催化剂对乙苯脱氢制苯乙烯有较好的活性,当SiO_(2)的负载质量分数为20%时,乙苯转化率和苯乙烯选择性显著提高。SEM证明当SiO_(2)负载质量分数为20%时,TiO_(2)-SiO_(2)催化剂表面较光滑,颗粒细小且分布均匀,并呈现疏松多孔状结构。

TiO_(2)-SiO_(2) catalysts were prepared by the sol-gel method,and the effect of SiO_(2) loading on activity and stability of the TiO_(2)-SiO_(2) catalyst was studied.The effects of reaction temperature,ethylbenzene space velocity,and catalyst particle size on ethylbenzene dehydrogenation to styrene were investigated.The catalysts were characterized by BET and SEM.The results show that the TiO_(2)-SiO_(2) catalyst has a good activity for the dehydrogenation of ethylbenzene to styrene;When the SiO_(2) loading was mass fraction of 20%,the conversion of ethylbenzene and the selectivity of styrene were significantly improved.SEM proved that the surface of the TiO_(2)-SiO_(2) catalyst with SiO_(2) loading was 20%was smooth,the particles were fine and uniformly distributed,and the structure was loose and porous.