Production of hydrogen by partial oxidation of methanol over carbon-supported copper catalysts

Copper–zinc catalysts deposited by impregnation on different oxidised carbon supports (activated carbon, black carbon and carbon fibres) were tested in the partial oxidation of methanol (POM) (CH3OH + ½ O2 → 2 H2 + CO2). Characterisation of the samples by N2 adsorption, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed differences in the dispersion, location and relative distribution of the active phase on the surface of the carbonaceous supports. These properties have important implications in the catalytic behaviour of the samples in the POM reaction. The location of active phases on the microporous structure implies lower initial activities and better thermal stability. These results may be due to limitations in the access of the reagents to the active phase and the prevention of copper-sintering effects.