Wednesday, October 19, 2011
Exhibit Hall B (Minneapolis Convention Center)
The chemical looping hydrogen production process uses synthesis gas or methane to reduce a metal oxide material, forming a waste stream of CO2 and H2O from which CO2 can be easily sequestered. The reduced metal oxide is then oxidized with steam to produce pure H2 and regenerate the original metal oxide. This system requires a metal oxide material that can achieve high H2 and CO conversions to H2O and CO2 during the reduction step while maintaining fast oxidation and reduction kinetics that do not degrade over time. In this study, the use of nano-scale cobalt- and nickel-ferrite (CoFe2O4 and NiFe2O4) based materials was investigated for chemical looping hydrogen production. Nano-thin films of ferrite were deposited on a high surface area ZrO2 support material using the atomic layer deposition (ALD) process to minimize sintering and diffusion limitations on reaction kinetics. The kinetics and cyclability performance of these thin film materials were analyzed and compared with the performance of conventionally made impregnation ferrite samples.