Catalytic Conversion of Carbon Dioxide to Methanol over Homogeneous and Heterogeneous Hybrid Catalyst

Carbon dioxide is the final and inevitable product of the utilization of fossil fuels. Since it is  thermo-dynamically stable, there seems to be difficult to convert it back to useful chemical products. Hydrogenation of carbon dioxide to fuels such as methanol, higher alcohols and hydrocarbons can be considered as a promising route to use carbon dioxide as a feedstock to produce valuable chemicals rather than as a waste with a cost of disposal. In this work, modified copper-based catalysts were prepared by conventional co-precipitation method with the addition of small amount of transition metal for the hydrogenation of carbon dioxide to alcohols via reverse water gas shift reaction. The catalysts were characterized by TPR, TEM, ICP, XRD, BET, PSA, FT-IR, XPS methods. The prepared heterogeneous catalysts were tested in a CSTR with the addition of alcohols used as homogeneous catalyst at low temperature of 160oC. The effect of the type of alcohols as homogeneous catalyst on the activity toward hydrogenation was observed profoundly. In-situ DRIFTS(Diffuse Reflectance Infrared Fourier Transform Spectroscopy) analysis was conducted to trace the reaction mechanism for CO2 gydrogenation to methanol.