Nickel-based catalysts: Dependence of properties on nickel loading and modification with palladium

Abstract

The aim of this study was comparative analysis of catalysts with 5 and 20 wt. % Ni loading, with and without Pd additive, and it included: determination of reduction degrees, investigation on microstructure by scanning electron microscopy and chemical analysis by energy-dispersive spectroscopy. Ni/Al2O3 and Ni-Pd/Al2O3 catalysts supported on α-Al2O3-based foams were synthesized by aerosol assisted impregnation. Impregnation of the foams by ultrasonically aerosolized chlorides was followed by drying at 473 K and hydrogen reduction at 533 and 633 K. Lower Ni loading resulted in higher reduction degrees. Ni loading of 20 wt. % enabled relatively uniform coverage of the foam with a metallic coating. With activity modifier (Pd), nearly complete reduction was achieved at both temperatures. Reduction degrees reached 99.4 and 98.2 wt. % at 533 K for 5 and 20 wt. % of Ni, respectively. [Projekat Ministarstva nauke Republike Srbije, br. 34033: Innovative synergy of by-products, waste minimization and clean technologies in metallurgy]

Keywords

• catalysts
• Ni
• Pd
• modification
• α-Al2O3-based foam
• aerosol assisted impregnation