Production of hydrogen and value-added carbon materials by catalytic methane decomposition: a review

Dihydrogen (H-2), commonly named "hydrogen", is attracting research interest due to potential applications in fuel cells, vehicles, pharmaceuticals and gas processing. As a consequence, the recent discoveries of natural gas reservoirs have prompted the development of technologies for methane conversion to hydrogen. In particular, the catalytic decomposition of methane is a promising technology to generate COx-free hydrogen and multi-wall carbon materials. Carbon nanomaterial byproducts can be used in electronics, fuel cells, clothes, and for biological and environmental treatments. Recent research has investigated the performance of hydrogen production and the characteristic of carbon nanomaterials. Here, we review the decomposition of methane on Ni-based catalysts, with focus on the influence of reaction temperature, gas hourly space velocity, support, and promoter. Ni-based catalysts allow CH4 conversion higher than 70% with H-2 yield of about 45% at more than 700 degrees C. We present catalyst regeneration by various techniques such as combustion. Reactors used for catalytic decomposition of methane include fluidized bed, fixed-bed and plasma reactors.