The large-scale consumption of fossil fuels has raised CO₂ levels to surpass the 400 ppm threshold, and the new scenario puts energy-related CO₂ emissions on a slow upward trend in the next decades [1]. Given the vastness of CO₂ supplied to the atmosphere, it makes sense to consider CO₂ a resource rather than a waste for its transformation into new products in a CCU approach. It is also being recognized that exploiting part of the captured CO₂ to generate value from it can complement its storage via CCS, thus contributing to achieve the 2030 emissions reductions targets that align with reaching net zero by the middle of the century, as committed at COP26 climate change conference [2]. CO₂ can be activated and chemically converted through different approaches such as thermochemical and biochemical methods, and more innovative technologies such as the electro-, photo-, or- photoelectro-chemical reduction [3]. These latter sustainable technologies are appealing, since they could enable an economically competitive industrial production of CO₂-based chemicals (e.g. HCOOH, CH₃OH, or C₂H₄, among others) by using renewable energy, contributing to rebalance the carbon cycle. Since CO2 is a thermodynamically stable molecule, its multistep reduction is challenging and confronts many fundamental technical hurdles. The kinetics for CO₂ reduction are also, in general, more sluggish than the thermodynamically favorable two-electron H2 evolution reaction, which competes with CO₂ reduction.  

The author presents the latest results obtained in the continuous conversion of CO₂ to valuable products in the Development of Chemical Processes and Pollution Control (DePRO) research group at the Chemical and Biomolecular Engineering Department of the University of Cantabria. The achievements so far in the group are exciting and the author believes that with continued research efforts these sustainable technologies for CO₂ conversion may become technically and economically feasible in the near future.