Catalytic Co_2/H_2 Methanation Reaction Over Alumina Supported Manganese/Cerium Oxide Based Catalysts

摘要

The methanation reaction is a promising method for the purification of natural gas, in which the acid gas of CO_2, is eliminated by catalytic conversion. The advantage of catalytic technology is the utilization of CO_2 present for the production of methane gas. The used of alumina supported cerium oxide as the based catalyst in CO_2/H_2 methanation reaction have been investigated in this research by using manganese as the dopant and ruthenium as the co-dopant via wet impregnation technique. The series of cerium oxide catalysts calcined at 400°C for 5 hours had been prepared at the screening stage. Then, the catalysts were optimized by different calcination temperatures and different based oxide loadings. The potential catalysts of Ru/Mn/Ce (5:35:60)/Al_2O_3 calcined at 700°C gave 100% of CO_2 conversion by using Fourier Transform Infrared (FTIR) spectroscopy and yielded about 80% of CH_4 at reaction temperature of 400°C. X-ray Diffraction (XRD) analysis showed that the supported catalysts were amorphous in structure. Field Emission Scanning Electron Microscopy (FESEM) analysis illustrated the surface of the catalysts were covered with small and dispersed spherical particles. Energy Dispersion X-ray (EDX) analysis revealed that there was 1.02% reduction of Ru in the Ru/Mn/Ce (5:35:60)/Al_2O_3 used catalysts compared to fresh catalysts. Meanwhile Nitrogen Adsorption (NA) analysis showed that Ru/Mn/Ce (5:35:60)/Al_2O_3 catalyst attained surface area of 143.10 m~2/g at 700°C.