Influence of Operating Parameters, Al2O3 and Ni/Al2O3 Catalysts on Plasma-Assisted CO2 Reforming of CH4 in a Parallel Plate Dielectric Barrier Discharge for High H2/CO Ratio Syngas Production

This work aimed to investigate plasma-assisted CO(2)reforming of CH(4)in a parallel plate dielectric barrier discharge (DBD) system for production of high H-2/CO ratio syngas. The effects were studied of operating parameters (discharge frequency and applied voltage), Al(2)O(3)and Ni/Al(2)O(3)catalysts on the CH(4)dry reforming performance in terms of reactant conversion, coke, product selectivity, energy consumption, and energy efficiency. In order to improve H-2/CO ratio of the produced syngas, a high CH4/CO(2)feed molar ratio of 4/1 was tested for the dry reforming of CH4. As compared to a DBD-alone system, a combined Al(2)O(3)catalyst-DBD system operating at an applied voltage of 11 kV, a discharge frequency of 750 Hz and an Al(2)O(3)packing of 6.4 g gave an improved H(2)and CO selectivity of 79% and 28%, respectively, with a fraction of syngas of 0.97 and a relatively high H-2/CO ratio of 2.4. An application of 5 wt% Ni/Al(2)O(3)catalyst in the DBD further improved the H(2)selectivity to 84% and the CO selectivity to 47%. In addition, the syngas fraction increased to 0.98 with an H-2/CO ratio of 1.5, while the amount of coke decreased from 4.7 to 3.7 wt%.