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Highlights: [•] IGC was used to study surface property of MCF loaded with the sized Ni particle. [•] High adsorption free energy and heat of aromatics on MCF with ca. 5nm Ni particle. [•] Strong dispersive and specific interaction on MCF with small Ni particle (<1.4nm). [•] Ni highly dispersed on MCF promotes the great interaction with aromatics structure. [Copyright &y& Elsevier]

Abstract: The pore structure of mesoporous silica KIT-6 has been systematically tuned via the variation of calcination temperature (773–1223K), with the mesopore size ranging from 4.8 to 7.5nm and micropore volume from 0.000 to 0.078cm3/g, respectively. Four n-alkanes (C6–C9), cyclohexane, benzene, toluene, trichloroethylene, and tetrachloroethylene were employed as probe molecules in the evaluation of the pore structure effect on KIT-6 surface property using inverse gas chromatography (463.2–493.2K). High free energy of adsorption and enthalpy of adsorption were observed on the KIT-6 with the micropore volumes. The dispersive interaction parameter , and specific interaction parameter I SP, were found to decrease with the increment of the mesopore size of the samples. These results indicate that the occurrence of micropore contributes the adsorption, while the narrow mesopore of KIT-6 promotes the dispersive and specific interaction. [Copyright &y& Elsevier]

Abstract: Catalysts containing rhodium (Rh) were prepared by the wet impregnation method using H-β-zeolite as support. Retention time of three n-alkanes (C5–C7), cyclohexane, benzene, trichloroethylene and tetrachloroethylene on the Rh/H-β-zeolite catalysts (0.5–2.0wt% of Rh) and H-β-zeolite were measured by inverse gas chromatography (IGC) in the 473.2–513.2K temperature range. Standard free energy of adsorption, dispersive component of surface free energy of adsorbent and specific interaction parameters between polar probes and catalysts were evaluated. The results indicate that the adsorption characteristics of H-β-zeolite can be modified by rhodium. Surface area, enthalpy of adsorption and dispersive component of surface free energy decrease after the impregnation of rhodium. Besides, it was found that rhodium dispersed in the framework of H-β-zeolite had special adsorption for benzene which may be useful for making catalysts for certain reactions involving benzene in the future. [Copyright &y& Elsevier]