催化裂化催化剂LZR-20的柠檬酸改性研究

STUDY ON MODIFICATION OF FCC CATALYST LZR-20 BY CITRIC ACID

对高温焙烧后的LZR-20催化剂进行了柠檬酸改性,采用X射线衍射仪、X射线荧光光谱仪、N2吸附、磨损指数仪对改性后的催化剂进行了表征。结果表明:柠檬酸改性前后,催化剂的结晶度和稀土含量变化较小,磨损指数虽有所升高,但随着柠檬酸处理前催化剂焙烧温度的升高,磨损指数逐渐下降;改性后催化剂的介孔孔体积和比表面积明显增加,且介孔孔体积随改性前催化剂焙烧温度的升高而增大;经800℃焙烧后再经柠檬酸处理的催化剂,与改性前相比,重油产率下降0.99%,总液收增加0.90%。

The catalyst LZR-20 was calcined at high temperature and then treated with citric acid.The modified catalyst was characterized by XRD,XRF,N2 adsorption and attrition index determinator.The results showed that the crystallinity and rare earth content of the catalyst changed little before and after citric acid modification,but the attrition index decreased with the increase of calcination temperature before citric acid treatment.N2 adsorption characterization showed that the mesoporous volume and mesoporous surface area of the modified catalyst increased significantly,and the mesoporous volume increased with the increase of calcination temperature before modification.The evaluation results showed that compared with the catalyst before modification,the modified catalyst calcined at 800℃before treated with citric acid could reduce the yield of heavy oil by 0.99%,and increase the total liquid yield by 0.90%。