Hydrodesulfurization of catalytic cracked gasoline-selective catalytic cracked gasoline hydrodesulfurization using Co-Mo/#gamma#-Al-2O_3 catalyst modified by pyridine-

摘要

The effects of pyridien modification on the catalyst activity and selectivity of Co-Mo/#gamma#-Al_2O_3 were investigated in thiophene hydordesul furiization(HDS) and olefin hydrogenation (HG).Pyridine injection into the reactant at 150degC.Inhibition of thiophene HDS was totally recovered after the temperature was raised to 300degC for a while.However,inhibition of diisobutylene and 1-octene HG persisted after the same temperature rise. The possibility of improving the HDS selectivity (higher activity for HDS and lower activity for olefin HG) by pyridine mossibility(i.e.pyridine injectio at 150degC and partial pyridine desorption at 300degC) was investigated for HDS reactions of model gasolines and catalytic cracked gasoline (CCG).Thiophene HDS was little affected,but benzothiophene HDS was slightly inhibited.Olefin HG and thiol roduction reaction were strongly inhibited.Improvement of HDS selectivity was observed in the reactions of model gasolines and CCCG after pyridine modification.The fall in octanevalue became smaller.Improvement of HDS selectivity by pyridine modification was considered to result from the selective deactivation of the active sites for olefin reactions (HG and thiol production).