Influence of Nature Support on Methane and CO2 Conversion in a Dry Reforming Reaction over Nickel-Supported Catalysts

摘要

A promising method to reduce global warming has been methane reforming with CO2, as it combines two greenhouse gases to obtain useful products. In this study, Ni-supported catalysts were synthesized using the wet impregnation method to obtain 5%Ni/Al2O3(SA-5239), 5%Ni/Al2O3(SA-6175), 5%Ni/SiO2, 5%Ni/MCM41, and 5%Ni/SBA15. The catalysts were tested in dry reforming of methane at 700 °C, 1 atm, and a space velocity of 39,000 mL/gcat h, to study the interaction of Ni with the supports, and evaluation was based on CH4 and CO2 conversions. 5%Ni/Al2O3(SA-6175) and 5%Ni/SiO2 gave the highest conversion of CH4 (78 and 75%, respectively) and CO2 (84 and 82%, respectively). The catalysts were characterized by some techniques. Ni phases were identified by X-ray diffraction patterns. Brunauer–Emmett–Teller analysis showed different surface areas of the catalysts with the least being 4 m²/g and the highest 668 m²/g belonging to 5%Ni/Al2O3(SA-5239) and 5%Ni/SBA15, respectively. The reduction profiles revealed weak NiO-supports interaction for 5%Ni/Al2O₃(SA-5239), 5%Ni/MCM41, and 5%Ni/SBA15; while strong interaction was observed in 5%Ni/Al₂O₃(SA-6175) and 5%Ni/SiO₂. The 5%Ni/Al₂O₃(SA-6175) and 5%Ni/SiO₂ were close with respect to performance; however, the former had a higher amount of carbon deposit, which is mostly graphitic, according to the conducted thermal analysis. Carbon deposits on 5%Ni/SiO₂ were mainly atomic in nature.