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2 Polish Journal of Chemistry

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Direct Transformation of Ethanol to Ethyl Acetate over MoSx/C Catalyst

Wang L. X., Zheng D. F., Ma C. X., Zhu W. C., Liu S. Y., Cui J., Wang Z. L., Zhang W. X.

Polish Journal of Chemistry

2009

Vol. 83, nr 11

1993-2000

Activated carbon-supported sulfided molybdenum catalysts were tested in transformation of ethanol to ethyl acetate. The catalytic activity of MoSx/C catalysts was found to depend strongly on preparation procedure. Surface atomic ratio of S/Mo on these catalysts was different and the catalyst with the ratio of S/Mo = 2.2 had better catalytic properties. For the purpose of enhancement of catalytic activity, the treatment of activated carbon support by HNO3 had been applied. Physicochemical characterization showed that the pretreatment was effective in obtaining a highly dispersed molybdenum species on the surface of the catalyst, which led to an in crease in conversion of ethanol.

Surface Structure and Catalytic Properties of Cu/SiO2 Catalysts Prepared by Different Methods

Ji D. H., Zou X. J., Zheng D. F., Wang L. X., Liu S. Y., Zhu W. C., Wang G. J., Wang Z. L.

Polish Journal of Chemistry

2008

Vol. 82, nr 5

1097-1104

The silica supported copper catalysts were prepared via impregnation (IM), solgel (SG) and deposition precipitation (DP) methods. The catalysts were characterized by XRD, H2-TPR, NH3-TPD, H2-N2O titration, XPS, BET and EPR techniques. The results indicated that two copper species, Cu2+ and Cu0 exist on the surface of SG catalyst; how ever, only Cu0 species could be found on the surface of reduced IM and DP catalysts, and the dispersion of Cu0 on IM catalyst was better than that on DP catalyst. According to the reaction results, Cu0 should be the active sites for dehydrogenation of cyclohexanol. Cu2+ species on the surface of SG catalyst might be responsible for the dehydration of cyclohexanol. The residual Na was found on the surface of DP catalyst, which made the acidity decreas ing, and the Cu crystallite growing up easily.