Hydrogen and syngas production through dynamic chemical looping reforming-decomposition of methane

摘要

This work introduces CeZr0.5GdO4 spinel particles as novel oxygen carriers for use in the reforming and decomposition of methane into H-2 and CO via the chemical looping technique. These particles were prepared by a modified sol-gel combustion method to increase their reactivity by increasing the surface area and consequently more accessibility of the gas feed to the solid phase. The performance of the synthesized materials was dynamically evaluated in terms of activity and stability at different operating temperatures (800-900 degrees C). The air used in the oxidation step eliminates almost all of the deposited solid carbon and converts it to CO, while providing the oxygen consumed in the reduction step. Oxygen carrier particles showed a conversion of more than 90 in all cycles after about 30 min of reduction operations. By the optimal operating path proposed in this research, more than 90 of the reactor exhaust gas is allocated to the production of H-2 and CO with almost complete elimination of CO2 and H2O in a shorter period of time. This will also reduce the time required for coke gasification and lattice oxygen replenishment of the spinel. Finally, the CeZr0.5GdO4 proved to be a successful oxygen carrier for the continuous production of hydrogen and carbon monoxide with almost no remarkable reduction in activity during successive redox cycles. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.