A Char-Supported Nano-NiO Catalyst for Biomass Syngas Cleanup and Conditioning

A newly developed nano-NiO on char catalyst was evaluated for syngas cleanup and conditioning in an updraft biomass gasifier. The nano-Ni/char catalyst was prepared by mechanically mixing nano-sized NiO powder with char particles. Its performance in terms of tar removal and syngas composition enhancement was compared with Ni/char and Ni/γ-Al₂O₃ catalysts under various reforming conditions. The nano-Ni/char catalyst removed more than 99% of tars in the syngas, exhibiting similar or better catalytic performance than Ni/γ-Al₂O₃ at the same conditions, especially at relatively low temperatures, smaller NiO loadings, or shorter residence times. Its performance was also better than Ni/char catalyst in all cases. Meanwhile, the nano-Ni/char catalyst also enhanced H₂ and CO concentrations in syngas, up to 36.73 vol% and 29.52 vol%, respectively. Furthermore, the nano-Ni/char catalyst did not deteriorate during the 8 h continuous durability test.