Combustion Synthesis of Copper-Nickel Catalysts for Hydrogen Production from

Ethanol

Anand Kumar1, Rahul R Bhosale1, LJP van den Broke1, A S Mukasyan2, E E Wolf2

1. Department of Chemical Engineering, Qatar University, Doha, Qatar

2. Department of Chemical and Biological Engineering, University of Notre Dame, IN, USA

Cu and Ni based catalysts were synthesized using solution combustion synthesis method. The catalyst synthesis parameters (such as fuel to oxidizer ratio, combustion temperature) were monitored and correlated with the synthesized materials properties. The catalytic activity and hydrogen selectivity were investigated for ethanol decomposition reaction. The amount of fuel content in the combustion solution was found to greatly affect the phase and the microstructure of the synthesized catalyst. In situ x-ray absorption spectroscopy (XAS) studies were carried out to study the reduction of the catalyst containing mixed oxides of copper and nickel. The reduced catalyst was further subjected to an oxidizing environment to collect the in-situ XAS data during the oxidation of the catalyst. As shown in Figure 1, these investigations indicate that the catalyst oxidation state changes rapidly and most of the catalyst gets reduced (or oxidized) in the first few minutes of the reduction (or oxidation) process and then this effect gradually slows downs, and the actual catalysts used during the reaction could be entirely different (in terms of oxidation state, microstructure) than the initially synthesized catalyst.

Figure 1: Reduction and re-oxidation of CuNi catalysts