LaFe0.8Co0.15Cu0.05O3 Supported on Silicalite-1 as a Durable Oxygen Carrier for Chemical Looping Reforming of CH4 Coupled with CO2 Reduction.

Abstract

Chemical looping reforming of CH4 coupled with CO2 reduction is a novel technology for the utilization of CH4 and CO2. Here, we report a durable and outstanding LaFe0.8Co0.15Cu0.05O3/S-1 oxygen carrier at lower operating temperature to efficiently convert CH4 and utilize CO2. LaFe0.8Co0.15Cu0.05O3 showed a high CH4 reaction rate (7.0 × 10-7 mol·(g·s)-1), CO selectivity (84.2%), and CO yield (0.045 mol·g-1) at 800 °C. However, the reactivity of LaFe0.8Co0.15Cu0.05O3 reduced quickly with the redox cycles. The introduction of Silicalite-1 promoted the performance of the LaFe0.8Co0.15Cu0.05O3 perovskite oxygen carrier during the redox cycles. It can be attributed to the fact that under heat treatment, the LaFe0.8Co0.15Cu0.05O3 particles grew along the edge of Silicalite-1 and the LaFe0.8Co0.15Cu0.05O3 nanoparticles were homogeneously dispersed on the Silicalite-1 surface, which improved the thermal stability and reactivity of the oxygen carrier. In addition, the interface between Silicalite-1 and LaFe0.8Co0.15Cu0.05O3 nanoparticles also played important roles because the porous structure of Silicalite-1 could reduce the mass transfer restriction of the interface. In addition, Silicalite-1 also possessed high CH4 and CO2 adsorption selectivity, leading to higher reactivity.