Hydrogen peroxide mediated thermo-catalytic conversion of carbon dioxide to C1-C2 products over Cu (0)

The global challenge concerning carbon dioxide (CO2) conversion to valuable products is anticipated to execute an essential task towards net zero carbon emissions. Thermal CO2 reduction is advantageous in terms of higher conversion rates, selectivity, and already-established thermal instruments for scalability. However, the method is energy-intensive, a hindrance to sustainably practical adoption. Herein, we present a comprehensive study of H2O2-mediated thermal CO2 conversion in the presence of dendritic zerovalent copper (d-ZCu) in a batch-type reactor, yielding C1 and C2 carbon products, with acetic acid (AcOH) as the major product (achieving an optimized yield of approximately 0.98 M and a selectivity of around 97 % at near ambient conditions of 25–150 °C and 1–15 bar), along with trace amounts of methanol (MeOH) and ethanol (EtOH), and carbon monoxide (CO) as a gaseous product. The reaction parameters, including temperature, time, pressure, and concentrations, were optimized to gain better insight into the reaction. To further explore the feasibility of the process, experiments were performed in a continuous flow-packed bed reactor using similar parameters as those in the batch reactor, where CO was identified as the major product of CO2 reduction. For advanced real-life applicability, the as-emitted exhaust gases from diesel and petrol engines, as sources of anthropogenic CO2, were utilized to establish the practical applicability of the proposed method.