Synthesis gas generation by chemical-looping reforming in a continuously operating laboratory reactor

Chemical-looping reforming is a technology that can be used for partial oxidation and steam reforming of hydrocarbon fuels. This paper describes continuous chemical-looping reforming of natural gas in a laboratory reactor consisting of two interconnected fluidized beds. Particles composed of 60 wt% NiO and 40 wt% MgAl2O4 are used as bed material, oxygen carrier and reformer catalyst. There is a continuous circulation of particles between the reactors. In the fuel reactor, the particles are reduced by the fuel, which in turn is partially oxidized to H2, CO, CO2 and H2O. In the air reactor the reduced oxygen carrier is reoxidized with air. Complete conversion of natural gas was achieved and the selectivity towards H2 and CO was high. In total, 41 h of reforming were recorded. Formation of solid carbon was noticed for some cases. Adding 25 vol% steam to the natural gas reduced or eliminated the carbon formation.