In Situ Modification of CuO-FeO by Nonthermal Plasma: Insights into the CO-to-CHOH Hydrogenation Reaction.

The hydrogenation of CO to CHOH on the binary mixed metal oxides of CuO-FeO under nonthermal plasma discharge has been reported in this study. The catalysts are synthesized using the sol-gel route and characterized by XRD, FTIR, SEM, and XPS techniques. The impact of CuO mixing with FeO on CO conversion and CHOH yield has been investigated. Herein, we have compared two distinct techniques, namely thermal and plasma catalytic processes. The overall outcome shows that the CO conversion and CHOH production increase with an increase in CuO mixing with FeO. The synthesized catalyst does not show significant CO conversion and CHOH formation in the thermal catalytic process (100-250 °C). Interestingly, when plasma discharge is combined with thermal heating, CO conversion and CHOH production significantly improve. The plasma discharges in the CO/H gas stream, at low temperatures (<200 °C), reduce Cu to Cu and Fe to Fe, which could probably enhance the CO conversion and CHOH production. Among the catalysts prepared, 15% CuO-FeO exhibited the best catalytic activity with 13.2% CO conversion, 7.3% CHOH yield, and a space-time yield of 13 mmol/h g, with 4.67 kJ/L of specific input energy (SIE). The CHOH space-time yield is 2.9-fold higher than that of the commercial catalyst Cu/ZnO/AlO, which is operated at 30 °C with 45.45 kJ/L SIE.