提高甲烷芳构化催化剂强度的成型工艺研究

Shaping process for improving the strength of methane dehydroaromatization catalyst

采用室温浸渍旋蒸工艺制备Mo/HZSM-5甲烷芳构化催化剂,制备的催化剂粉体在无粘结剂的条件下进行喷雾成型。通过对喷雾成型过程中的影响因素进行考察,得出最佳喷雾成型条件,即在浆料配比为催化剂固含量40%,PVA加入质量分数1%,进料速度为70mL/min,干燥进风口温度220～230℃,出口温度100～105℃,雾化器变频器频率为70Hz的条件下,在此条件下可以得到符合粒径要求且收率相对较高的成型催化剂。成型后的催化剂经过干燥和焙烧即得到成品催化剂,催化剂的装置评价结果表明,采用此方法所得到的催化剂甲烷转化率和总芳烃选择性高,磨损指数低。

The methane dehydroaromatization catalyst Mo/HZSM-5 was prepared by a room temperature impregnation-rotary evaporation process,and the prepared catalyst powder was shaped without binder.The influencing factors in the spray shaping were investigated,and the optimal spray shaping conditions were obtained as follows:the catalyst solid content in the slurry of 40%by mass,the PVA content of 1%by mass,the feed rate of 70mL/min,the tuyere temperature and air outlet temperature for dryingof 220-230℃ and 100-105℃ respectively,and the nebulizer frequency converter of 70Hz.Underabove conditions,the shaped catalyst could meet the particle size requirement and has a relatively high yield.The shaped catalyst was dried and calcined to obtain a finished catalyst.The evaluation results of the catalyst exhibited higher methane conversion and total aromatics selectivity and lower wear index.