关键词: 2-苯基环己硫醇；WS₂, 脱硫；环烷基C-S键；哌啶；SiO₂, γ-Al₂O₃

Abstract: 2-Phenylcyclohexanethiol (2-PCHT) was synthesized. WS₂/Al₂O₃ and WS₂/SiO₂ were prepared by the incipient wetness impregnation, and characterized by X-ray diffraction (XRD), N₂ physical adsorption and transmission electron microscope (TEM). The desulfurizations of 2-PCHT over WS₂ catalysts supported on γ-Al₂O₃ and SiO₂ were investigated in the presence or absence of H₂. At 240 ℃ and under 5.0 MPa H₂, 2-PCHT undergoes desulfurization over the supported WS₂ catalysts via three parallel pathways: β elimination, hydrogenolysis and dehydrogenation. β elimination and hydrogenolysis are the two major pathways, and the reaction velocity in β elimination pathway is much faster than that in the hydrogenolysis pathway. Under Ar atmosphere, the parallel pathways are β elimination, homolytic C-S bond cleavage or hydrogenolysis, and dehydrogenation, withβ elimination serving as the dominate pathway. Piperidine strongly inhibits the β elimination pathway and the dehydrogenation pathway. It does not affect the hydrogenolysis pathway, and facilitates the homolytic C-S bond cleavage pathway. WS₂/Al₂O₃ is superior to WS₂/SiO₂ in the desulfurization of 2-PCHT, which is due to the higher dispersion of active phase. The kinetics of the desulfurization of 2-PCHT under H₂ is reasonably fitted by a pseudo-first-order model, whereas that under Ar cannot be described by the power-law rate expression, suggesting that the desulfurization of 2-PCHT is complex.

Key words: 2-phenylcyclohexanethiol, WS₂, desulfurization, cycloalkyl C-S bond, piperidines, SiO₂, γ-Al₂O₃