Conversion of dry biogas in a chemical looping reforming unit: Performance of Fe and FeMn-based oxygen carriers

Abstract

Biogas conversion is a renewable alternative for producing hydrogen. In this work, dry reforming of simulated biogas was performed in a 1 kWth continuous chemical looping reforming (CLR) unit in which the oxygen required for the partial oxidation of biogas to CO and H2 is supplied by an oxygen carrier. The performance of two different oxygen carriers (an iron oxide-based residue and a synthetic material based on an iron-manganese mixed oxide) was evaluated. The residue was capable of performing the dry reforming of biogas to a larger extent than the synthetic oxygen carrier. To enhance hydrogen yield, NiO addition was also considered with both materials. The presence of NiO increased methane conversion and H2 selectivity for both oxygen carriers. A value of approximately 2.6 mol H2/mol CH4 was achieved with both materials with the presence of only 2.7 wt% NiO in the bed.