Boosting syngas production from corncob tar reforming over Ni/MgAl hydrotalcite-derived catalysts

Abstract

In this work, various Mg-Al hydrotalcites with tailored morphologies were prepared by the co-precipitation method and then supported Ni using incipient impregnation for corncob tar reforming. Mg-Al hydrotalcites prepared under a pH of 10 and subsequently supported 20 wt% Ni (Ni/MgAl-10) exhibited excellent activity in syngas production (26.3 mmol/g) from corncob tar reforming at 600 °C. For a better understanding of the activity of the obtained catalysts, their activities for steam reforming of toluene (SRT) were investigated. In comparison with commercial Ni/Al2O3 and other Ni/MgAl hydrotalcite-derived catalysts, Ni/MgAl-10 had higher stability in SRT at 550 °C, which maintained >90% of toluene conversion during 10 h time-on-stream. The characterizations indicated that the excellent performance of Ni/MgAl-10 in both biomass tar and toluene reforming can be attributed to high dispersion of Ni particles, large specific surface area (119.9 m2/g), high reducibility (96%), and high basicity (1.33 mmol/gcat). Moreover, the kinetic study confirmed that Ni/MgAl-10 with a lower activation energy (23.5 kJ/mol) than commercial Ni/Al2O3 could exhibit better performance in SRT at low temperatures. The results could provide a design of a novel Ni-based catalyst and its application for tar reforming in the process of biomass gasification.