Jornal Internacional de Ciências Aplicadas - Pesquisa e Revisão Acesso livre

Abstrato

CO₂ hydrogenation to methane over Zeolite promoted Ni/CeO₂ Catalysts at Atmospheric Pressure

Abdullahi Isah*

The zeolite promoted Ni/CeO₂ catalysts were constructed via impregnation method and applied for conversion of CO₂ to methane at atmospheric pressure for the first time. The influence of calcination temperatures and operation conditions (such as reaction temperature, Gas Hourly Space Velocity (GHSV), H₂/CO₂ ratio) were studied. The results uncovered that the non-promoted 10 wt% Ni/CeO₂ catalyst showed %CO₂ conversion and %CH₄ selectivity (about 99% CO₂ conversion and 35.5% CH₄ selectivity) and the zeolite (2-8 wt%) promoted 10 wt% Ni/CeO₂ catalysts recorded (about 99% CO₂ conversion and 0-17.6% CH4 selectivity) at 350 atmospheric pressure, gas hourly space velocity (GHSV) of 72000 SmL (gcat h)^-1 and the H₂/CO₂ ratio of 4. The zeolite promoter addition to 10 wt% Ni/CeO₂ clearly and significantly reduced the % CH₄ selectivity and this selectivity reduction is directly proportional to the quantity of the zeolite added. The physicochemical characterizations of the catalysts in terms of morphology, compositional phase, functional group, Brunauer Emmett Teller (BET) surface area (m²/g), total volume (m³/g), mesoporous volume (m³/g), average pore diameter (A), Ni metal surface area, average crystallite size (nm) were carried out with Scanning Electron Microscope (SEM), X-Ray Diffract meter (XRD), Fourier Transform Infrared spectrophotometer (FTIR), Brunauer Emmett Teller surface area analyzer, Debye-Scherrer equation, BJH method.