Abstract: A series of catalysts with various Cu/Zn/Al mass ratios were prepared by decomposition of CuZnAl hydrotalcite precursors at 600 ℃ and used for steam reforming of methanol. The effect of the Cu/Zn/Al mass ratio on the catalyst performance for steam reforming of methanol was investigated at 250 ℃ and WHSV of 3.28 h-1 with a H2O/CH3OH molar ratio of 1.3. Cu/Zn/Al ratio of 36.7/13.4/(17-28) was preferred for achieving good activity. The Cu content barely affected the phase composition of the catalysts and the reduction temperature of the CuO phase. However, the catalysts with much lower or higher Cu content showed low activity because of the less active sites or the unsuitable Cu/Zn ratios. Both higher and lower Zn content led to the phase transformation of the catalysts and therefore the catalysts were less active. Higher Al content facilitated the dispersion of CuO and increased the specific surface area of the catalysts, thereby promoting the activity. In addition, the Cu/Zn/Al ratio hardly affected the gas product composition.

Key words: copper oxide, zinc oxide, alumina, hydrotalcite, methanol, hydrogen, steam reforming, fuel cell