Synthesis Gas Production through Redox Cycles of Bimetallic Oxides and Methane

摘要

Fe2O3-Ce0.75Zr0.25O2 (Fe-CeZr) is presented as an oxygen carrier for the production of synthesis gas (H-2 + CO) and hydrogen from methane through redox cycles. Syngas production of Fe-CeZr samples was evaluated by TGA using 5% CH4/Ar (reduction) and 5% H2O/Ar (oxidation)redox cycles at 700 degrees C and GC analysis of the product gas. Fe2O3 (Fe), Ce0.75Zr0.25O2 (CeZr), Fe2O3-Ce0.75Zr0.25O2 (Fe-CeZr), Fe2O3-5Ce(0.75)Zr(0.25)O(2) (Fe-5CeZr), Fe-CeZr (Fe-CeZr-Ni) and Fe-5CeZr (Fe-5CeZr-Ni) with 5% mol Ni were synthesized by co-precipitation techniques from their nitrate salt precursors, while Fe-CeZr was impregnated with 2% mol Ni (Fe-CeZr-M-i). Characterization consisted in XRD and BET surface area. Selectivities towards the partial oxidation of methane for these materials were: 23.5% (Te), 25.5% (CeZr), 16.3% (Fe-CeZr), 31.9% (Fe-5CeZr), 99.4% (Fe-CeZr-Ni), 99.2% (Fe-5CeZr-Ni) and 99.4% (Fe-CeZr-NW). The results make evident the ability of these materials to produce syngas. Additionally, excess hydrogen was produced through the adverse decomposition of methane, which also produced deposited carbon over the surface of the materials. During the oxidation step, these materials were able to promote the gasification of the previously deposited carbon with water and samples Fe-CeZr-Ni, Fe-5CeZr-Ni y Fe-CeZr-Ni-i presented a reduction in carbon deposition and sintering among all studied materials.