CO2 valorization through chemical reactions attracts significant attention due to the mitigation of greenhouse gas effects. This article covers the catalytic hydrogenation of CO2 to methanol and dimethyl ether using Cu-Ho-Ga containing ZSM-5 and g-Al2O3 at atmospheric pressure and at temperatures of 210°C and 260°C using a CO2:H2 feed ratio of 1:3 and 1:9. In addition, the thermodynamic limitations of methanol and DME formation from CO2 was investigated at a temperature range of 100–400°C. | Turkish Journal of Chemistry Turk J Chem 2021 45 231-247 http chem TÜBİTAK Research Article doi kim-2009-66 CO2 hydrogenation to methanol and dimethyl ether at atmospheric pressure using Cu-Ho-Ga γ Al2O3 and Cu-Ho-Ga ZSM-5 Experimental study and thermodynamic analysis Cansu TUYGUN Bahar İPEK Department of Chemical Engineering Faculty of Engineering Middle East Technical University Ankara Turkey Received Accepted Published Online Final Version Abstract CO2 valorization through chemical reactions attracts significant attention due to the mitigation of greenhouse gas effects. This article covers the catalytic hydrogenation of CO2 to methanol and dimethyl ether using Cu-Ho-Ga containing ZSM-5 and g-Al2O3 at atmospheric pressure and at temperatures of 210 C and 260 C using a CO2 H2 feed ratio of 1 3 and 1 9. In addition the thermodynamic limitations of methanol and DME formation from CO2 was investigated at a temperature range of 100 400 C. Cu-Ho-Ga g-Al2O3 catalyst shows the highest formation rate of methanol µmolCH3OH gcat h and DME µmolDME gcat h as well as the highest selectivity towards methanol and DME at 210 C using a CO2 H2 1 9 feed ratio. In both the thermodynamic analysis and reaction results the higher concentration of H2 in the feed and lower reaction temperature resulted in higher DME selectivity and lower CO production rates. Key words CO2 hydrogenation to methanol dimethyl ether atmospheric pressure holmium gallium thermodynamic analysis 1. Introduction CO2 emissions to the atmosphere increased 15 billion metric tons from 1990 till 2020 because of the increasing fossil fuel usage in industry transportation and electricity generation. After the 2000s a decreasing trend in CO2 emissions was observed due to the uses of more environmentally friendly industrial technologies1 however CO2 concentration in the atmosphere continues to increase to a value of 410 ppm v v in 20202 . As .
