Hydrogen rich syngas from CO2 reforming of methane with steam catalysed by facile fusion-impregnation of iron and cobalt loaded MgAl2O4 catalyst with minimal carbon deposits

The newly synthesised catalysts via facile fusion-impregnation of iron and cobalt onto MgAl2O4 were successfully accomplished with relatively high surface area and pore volume which exhibited mesoporous structure with narrow pore distribution. These catalysts were employed for CO2 reforming of CH4 with steam which was carried out at different reaction temperatures of 700, 750, 800, 850 and 900 degrees C. Different metal loadings of cobalt at 5, 15, 25, 40 and 50 wt% were also synthesised to study the effect of catalytic activity on CH4 and CO2 conversion as well as H-2 yield. It was observed that CH4 and CO2 conversion achieved its highest value at Co loading of 25 wt%. Addition of steam, basic properties, lattice textural of MgAl2O4 and magnesium metal oxides were suggested to be factors that keep out the coke formation on catalyst surface. However, the metal loading of more than 40 wt% Co started to show declination of catalyst activity and formation carbon deposits on catalyst surface. This circumstance suggests an agglomerated particle condition that decreases the active sites and hampers the gasification of carbon on catalyst surface. Possible reaction pathways are proposed in this study to elucidate the engagement of Fe and Co in CH4 and CO2 activation as well as their combination with surface carbon which further eliminates the coke deposition. The removal of carbon by oxidation was examined by XRD, TEM, TPO, Raman spectroscopy and TGA, which concludes its mechanism through oxidation of metal particles and surface carbon gasification from lattice oxygen. (C) 2021 Energy Institute. Published by Elsevier Ltd. All rights reserved.