Effects of additives on nickel(II)-chloride hydrogen reduction for production of nanocomposite catalysts

Abstract

Catalysts based on nickel, as active component, exhibit suitable properties in various heterogeneous catalysis processes; however, they quickly deactivate due to deposits formation during exploitation and sintering at elevated temperatures. Considering that catalysts with several catalytic components possess enhanced catalytic properties, in present study the influence of temperature, time and additives (PdCl2, FeCl2 and CuCl2) on the reduction degree of nickel(II)-chloride by hydrogen have been investigated. The objectives of the study were selection of an appropriate catalytic activity modifier and development of a new synthesis method for nanocomposite catalysts production, which are characterized by enhanced properties compared to the commercial Ni/Al2O3 catalysts. Obtained experimental results clearly indicate that the best effect was achieved with addition of 0.1 wt. % PdCl2, whereby NiCl2 reduction degree was 58.16% at 653 K and Pd significantly increased the reduction rate. According to the obtained results, new technological synthesis method of nanocomposite Ni-Pd/Al2O3 catalysts was proposed, where Ni and Pd, as catalytically active components, are homogeneously dispersed in monolithic Al2O3 based ceramic foam.