Oxyfunctionalization of n-Hexadecane with Ozone in Presence of Metal Loaded Zeolites, pp. 237-289
Authors: (V. S. R. Rajasekhar Pullabhotla, S. B. Jonnalagadda - School of Chemistry, University of KwaZulu-Natal, Durban, South Africa)
Abstract: The functionalisation of saturated long chained hydrocarbons at moderate temperature and pressure conditions is explored. The scope of microporous materials as heterogeneous catalysts for the ozone initiated conversion of saturated higher hydrocarbons, n-C16 alkane to value added products at moderate reaction conditions is focused. The suitability of a range of zeolite materials doped with different metals (Pd, Ni, V and U) as catalysts was investigated and commercially available zeolites, Na-Y, Zeolite Beta and ZSM-5 were modified to increase their acidic sites by impregnating different metals on microporous zeolite supports. The catalyst materials investigated are microporous uni-dimensional and 3-dimensional zeolite material viz. U/Na-Y, U/ZSM-5 Si/Al-30, U/silica, Pd/Na-Y, Pd/Na-Y (calcined under N2 flow condition), Pd/ZSM-5, Pd/ZSM-5 (N2), Ni/Na-Y, Ni/Na-Y (N2), Ni/ZSM-5, Ni/ZSM-5 (N2), V/Na-Y, V/Na-Y (N2), V/ZSM-5 and V/ZSM-5 (N2). These materials were employed to improve the activity on conversion and selectivity of the catalytic ozonation of higher alkanes. The catalysts were characterized by powder X-ray diffraction, Scanning electron microscopy, Diffuse reflectance ultraviolet-visible spectroscopy (DR UV-Vis), Fourier-transform infrared spectroscopy and BET surface area analysis. The X-ray diffractograms of metal loaded zeolites showed the crystalline structure of microporous materials, the structure of ZSM-5 and Na-Y catalysts remained intact after the impregnation conditions. All the zeolite supports and metal loaded zeolites showed the characteristic bands in the FT-IR spectra, which are in good agreement with the literature. SEM images clearly pointed out the homogeneity in shapes for all samples.