Abstract

Catalytic activities in dry methane reforming (DRM) on activated carbon supported nickel catalysts Ni(5% w/w)/AC were studied as a function of different promoters. CaO (1 and 5% w/w), CuO (5% w/w) and ZnO (5% w/w) were impregnated after NiO. Methane conversion was followed in a fixed-bed reactor under mild conditions (650ºC, 1atm and pre-treatment under helium flow). The initial activities showed the following order: 6.3 > 6.1 > 5.6 > 5.1 > 4.2 > 3.0 > 1.3mmolCH4-converted.min-1.gcat-1 for NiMg(5%) > NiCa(1%) > NiMg(1%) > NiCa(5%)/AC > Ni/AC > NiZn/AC > NiCu/AC, respectively. However, different activities after 4 hours reaction was found: NiCa(5%) > NiMg(5%) > NiCa(1%) > NiMg(1%) > NiZn/AC > Ni/AC > NiCu/AC. The activity on NiCa(5%)/AC catalysts only decreased 8% after 4h reaction, while that Ni/AC, NiMg(1%)/AC, NiCa(1%)/AC, NiMg(5%)/AC, and NiCu/AC decreased 33%, 29%, 28%, 27% and 23%, respectively. On the contrary, activity on NiZn/AC catalysts increased 7% after 4h reaction. In conclusion, a remarkable effect of the CaO on catalyst was observed, both in activity and in stability of catalyst.