乙苯脱氢催化剂成型工艺研究

Study on the molding process of ethylbenzene dehydrogenation catalyst

采用干混法制备乙苯脱氢催化剂,考察了成型条件对其性能的影响。结果表明,与直接捏合挤条相比,采用先碾压后捏合挤条制得的催化剂其侧压强度和堆密度略高,但平均孔径有所减小;适宜水粉比应控制在0.18～0.24 mL/g;与常用添加剂炭黑相比,以羧甲基纤维素作添加剂,催化剂孔径明显增大,活性有所提高,但侧压强度明显降低;相对于实心圆柱体催化剂而言,中空圆柱体和齿轮形催化剂的侧压强度低,活性高。

The ethylbenzene dehydrogenation cata- lyst was prepared by dry blending method, and the effects of molding conditions on its performance were investigated. The results showed that compared with directly kneading- extruding catalyst, the catalyst made by milling first and then kneading -extruding process had slightly higher edgewise compression strength and bulk density and lower average aper- ture. The optimum ratio of water to powder was 0.18 - 0.24 mL/g. Compared with carbon black, using carboxymethyl cellulose as additive,the aper- ture of catalyst was increased obviously, so that the activity was also increased, but the edgewise com- pression strength decreased obviously. Compared with solid cylinder shaped catalyst, the hollow cylin- der and gear shaped catalysts, though poor in edge- wise compression strength, were better in activity.