Hydrodesulfurization of dibenzothiophene and its hydrogenated intermediates over sulfided Mo/gamma-Al2O3

作者：Wang Huamin; Prins Roel^*

来源：Journal of Catalysis, 2008, 258(1): 153-164.

DOI：10.1016/j.jcat.2008.06.005

• hydrodesulfurization
• HDS
• dibenzothiophene
• hydrogenated intermediates
• mechanism
• kinetics
• sulfided Mo/gamma-Al2O3

Two intermediates of dibenzothiophene (DBT)-tetrahydro-DBT (THDBT) and hexahydro-DBT (HHDBT)-were synthesized, and their hydrodesulfurization (HDS) mechanism was investigated over Mo/gamma-Al2O3 at 300-340 degrees C and 5 MPa in the absence and presence of H2S and 2-methylpiperidine. The rate constants of all steps in the kinetic network of the HDS of DBT were measured. THDBT underwent desulfurization by hydrogenolysis to 1-phenylcyclohexene, followed by hydrogenation to pherylcyclohexane. The desulfurization of HHDBT occurred by hydrogenolysis of the aryl C-S bond and then cleavage of the cycloalkyl C-S bond of the resulting thiol by elimination to I-phenylcyclohexene and by hydrogenolysis to phenylcycloliexane. H2S strongly inhibited the desulfurization of all three molecules but did not inhibit (de)hydrogenation. 2-Methylpiperidine also had a strong inhibitory effect, especially on (de)hydrogenation and, to a lesser extent, on desulfurization. The order of the inhibition of DBT, THDBT, and HHDBT was explained by the adsorption constants of these three molecules.

• 出版日期2008-8-15