Nb2O5/Al2O3 materials prepared by sol-gel method using aluminium hydroxychloride and potassium niobate solutions were used as supports for nickel catalyst. 2 wt. % Ni catalysts were investigated by temperatureprogrammed reduction, TEM, X-ray diffraction, hydrogen chemisorption and high-resolution transmission electron microscopy (HRTEM). Hydrodechlorination (HDC) of 1,2-dichloroethane (1,2-DCA) over alumina modified by niobia supported nickel catalysts led to formation of ethylene as desired product. Selectivity toward C2H4 increases from ~35% for 2%Ni/Al2O3 up to 90% for Ni/Nb2O5- Al2O3. This phenomenon is an effect of the coexistence of Nb2O5 and Al2O3. Niobia is preferentially located over alumina, shaping the overall catalytic behavior of Nb2O5 – Al2O3 supported catalysts. This phenomenon could be related with the changes between Brönsted and Lewis acidic active sites ratio. Temperature programmed hydrogenation (TPH) of post-reaction deposits showed that during HDC on catalysts surface both carbon and chlorine-containing species were formed. Application of regeneration procedure (3h, 10%H2/Ar, 600°C) for spent samples led to efficient reconstruction of active sites.
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