Cu_xMn_1-xFe₂O₄ as oxygen carrier for chemical looping steam methane reforming

Abstract

The spinel-ferrite structure (SFS) oxygen carrier (OC) CuxMn1-xFe2O4 with (x = 0.3, 0.5, 0.6, and 0.7) was synthesized by the co-precipitation technique to be used in the chemical looping steam methane reforming process (CL-SMRP). The SFS OCs were characterized using Fourier Transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDX), Thermogravimetric Analysis (TGA), and Brunauer-Emmett-Teller (BET). The Response Surface Methodology (RSM) based on the Box-Behnken model was employed to estimate the effects of independent variables and their interactions on the OC activity. The effects of temperature, OC, loading percentage, steam to methane molar ratio, the number of redox cycles on the H2 production yield (YH2), methane conversion(XCH4), and SCO/CO2 were determined. According to the analysis of variance (ANOVA) analysis, results indicated that the reaction temperature and the OC (x) have extremely significant effects on XCH4 and YH2. The maximum XCH4 of 98.7%, YH2of 81.02%, and SCO/CO2 of 6.54 were obtained at optimal value conditions such as 650 °C, SFS OC Cu0.6Mn0.4Fe2O4, S/C 2.5, and redox cycle 30.