Dry reforming of methane catalysed by molten metal alloys

Dry reforming of methane can so far afford syngas with equimolar CO and H-2, which is suboptimal for Fischer-Tropsch chemistry. Now a process is reported based on a Ni-In molten metal alloy catalyst that is capable of producing syngas with practically relevant H-2/CO ratios together with separable carbon. Dry reforming of methane usually affords low-quality syngas with equimolar amounts of CO and H-2. Here we report the high conversion of CH4 and CO2 to syngas and solid carbon through simultaneous pyrolysis and dry reforming of methane in a bubble column reactor using a molten metal alloy catalyst (65:35 mol% Ni:In). The H-2 to CO ratio can be increased above 1:1 using feed ratios of CH4:CO2 greater than 1:1 to produce stoichiometric solid carbon as a co-product that is separable from the molten metal. A coupled reduction-oxidation cycle is carried out in which CO2 is reduced by a liquid metal species (for example, In) and methane is partially oxidized to syngas by the metal oxide intermediate (for example, In2O3), regenerating the native metal. Moreover, the H-2:CO product ratio can be easily controlled by adjusting the CH4:CO2 feed ratio, temperature, and residence time in the reactor.