Catalysis Letters, Vol.94, No.1-2, 61-68, 2004
Activity and selectivity of a nanostructured CuO/ZrO2 catalyst in the steam reforming of methanol
Steam reforming of methanol for production of hydrogen can be carried out over copper based catalyst. In the work presented here, the catalytic properties of a CuO/ZrO2 catalyst (8.5 wt%) synthesised by a templating technique were investigated with respect to activity, long term stability, CO formation, and response to oxygen addition to the feed. The results were obtained using a fixed bed reactor and compared to a commercial methanol synthesis catalyst CuO/ZnO/Al2O3. It is shown that, depending on the time on stream, the temporary addition of oxygen to the feed has a beneficial effect on the activity of the CuO/ZrO2 catalyst. After activation, the CuO/ZrO2 catalyst is found to be more active ( per copper mass) than the CuO/ZnO/Al2O3 system, more stable during time on stream ( measured up to 250 h), and to produce less CO. Structural characterisation by means of X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) reveals that the catalyst (as prepared) consists of crystalline, tetragonal zirconia with small domain sizes ( about 60 Angstrom) and small/disordered crystallites of CuO.