Ni supported on natural clay of palygorskite as catalyst for dry reforming of methane: Thermodynamic analysis and impacts of preparation methods

Due to the serious greenhouse effects caused by methane and carbon dioxide, dry reforming of methane is one of the most effective ways for the sufficient utilization. The palygorskite supported Ni catalysts are prepared by 5 methods including deposition precipitation, impregnation, ultrasonic-assisted impregnation, hydrothermal precipitation, and ultrasonic-assisted hydrothermal precipitation, and their catalytic performances are experimentally evaluated in dry reforming of methane. As a result, the catalyst prepared by ultrasonic-assisted hydrothermal precipitation presents the highest catalytic activity with reactant conversions of 75.62% (CH₄) and 79.58% (CO₂), respectively. A few characterizations are conducted and the results confirm that the preparation method plays a crucial role in physicochemical property of catalysts. The optimal catalyst exhibits the homogeneous dispersion of active nanoparticles, large surface area and pore diameter, strong interaction between Ni component and palygorskite, and favorable strong basic sites.