HYDRODESULFURIZATION AND OLEFIN AROMATIZATION OVER Co-Mo/ZSM-5 ZEOLITE TREATED BY MIXED ALKLI

Abstract

Abstract:

ZSM-5 zeolites with different Si/Al ratios were treated by mixed alkali solution of Na2CO3 and TPAOH solution. The zeolites before and after alkali treatment were characterized by XRD, BET, SEM and NH3-TPD techniques. The results showed that the original zeolite frame structure was not destroyed after Na2CO3/TPAOH treatment, and the alkali treatment were beneficial to the increasing of specific surface area, external surface area, average pore size, and pore volume of mesoporous for HZ (80-4-0.2). With FCC gasoline as the raw material, the reaction of hydrogenation desulfurization and aromatic over CoMo/ZSM-5 catalyst prepared by ZSM-5 zeolites before and after alkali treatement were studied. At the certain reaction contion CoMo/HZ（80-4-0.2）showed the most desulfurization rate and the most yield of aromatization. The effect of process conditions on the reaction of hydrogenation desulfurization and aromatization of CoMo/HZSM-5(80-4-0.2) in a small fixed bed reactor was investigated. The results illustrated that when the reaction temperature was 400 ℃, the reaction pressure was 2.5 MPa, the reaction velocity was 1.5 h-1, the desulfurization rate was the higher, 94.2%., and the yield of aromatization was the larger, 30.82%.

Key words: desulphurization rate, hydrodesulfurization, aromatization, Na2CO3/TPAOH mixed alkali

References

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