NiCo@NiCo phyllosilicate@CeO_2 hollow core shell catalysts for steam reforming of toluene as biomass tar model compound

摘要

Developing sintering and carbon resistant tar removal catalysts is crucial for biomass gasification technology. Herein, for the first time, NiCo@NiCo phyllosilicate@CeO2 hollow core shell catalysts have been designed for steam reforming of toluene (SRT) as the biomass tar model compound. They show both good catalytic activity and stability within 45 h of time on stream due to their high sintering resistance of NiCo because of the strong interactions between NiCo and CeO2, high metal exposure as a result of the high specific surface area, high surface metal concentration as well as the high oxygen vacancies as evidenced from the H-2-Temperature-programmed reduction (H-2-TPR), H-2 chemisorption and X-ray photoelectron spectroscopy (XPS) characterizations respectively. Additionally, the synergistic effect between Ni and Co further improves their carbon resistant property. By comparison, Co@Co phyllosilicate@CeO2 catalysts perform the lowest toluene conversion and stability mainly due to their structural instability during reaction resulting from their high Si/Co ratio, leading to their low specific surface area and Co exposure. The outstanding SRT performance of NiCo@NiCo phyllosilicate@CeO2 catalysts indicates their promising application for steam reforming of biomass tar reaction.