Abstract
Copper catalysts supported on rice husk ash (Cu/RHA) were tested for partial oxidation of methanol (POM) to produce H-2. The catalysts were prepared by deposition-precipitation and characterized by ICP-AES, TGA, XRD, TPR, XPS and N2O titration techniques. The Cu/RHA catalyst with 10.2 wt.% Cu loading and under 673 K calcination has higher copper dispersion and smaller Cu particle size. This catalyst exhibits higher activity and selectivity for POM to produce H-2. The partial pressure Of O-2 plays an important role to determine the product distribution. Catalytic activity of the catalyst at different reaction temperatures shows that CH3OH conversion, H-2 selectivity and CO selectivity increase with rise in temperature. At different temperatures along with POM,several reactions such as methanol combustion, steam reforming of methanol, methanol decomposition, water gas shift and oxidation of CO and H-2 might be involved. Comparison of catalytic activity Of Cu/RHA and Cu/SiO2 catalysts demonstrates that Cu/SiO2 catalysts deactivate with time with faster rate and have higher CO selectivity. This proves that Cu/RHA catalysts have good thermal stability and selectivity for POM to produce H-2. (C) 2009 Elsevier BY. All rights reserved.