Catalytic Methanation over Natural Clay-Supported Nickel Catalysts.

The catalytic methanation reaction allows for the attainment of methane from carbon dioxide and hydrogen. This reaction is particularly interesting for the direct upgrading of biogas, which mainly contains methane and carbon dioxide, into biomethane. This work focused on the synthesis and evaluation of natural clay-supported nickel catalysts in the catalytic methanation reaction. Natural clay could be directly used as a low-cost catalyst support for the deposition of small nickel nanoparticles (1-15 nm) by the standard incipient wetness impregnation method. These catalysts showed high activity and excellent selectivity into methane and excellent catalytic stability (80% carbon dioxide conversion, nearly 100% methane selectivity at 500 °C, 1 bar, and WHSV = 17,940 mL·gcat-1·h-1 for 48 h on stream) and outperformed their counterparts prepared with an industrial alumina support as reference.