Loukia Pantzechroula Merkouri

Advanced catalytic materials able to catalyse more than one reaction efficiently are needed within the CO2 utilisation schemes to benefit from end-products flexibility. In this study, the combination of Ni and Ru (15 and 1 wt%, respectively) was tested in three reactions, i.e. dry reforming of methane (DRM), reverse water-gas shift (RWGS) and CO2 methanation. A stability experiment with one cycle of CO2 methanation-RWGS-DRM was carried out. Outstanding stability was revealed for the CO2 hydrogenation reactions and as regards the DRM, coke formation started after 10 h on stream. Overall, this research showcases that a multicomponent Ni-Ru/CeO2 -Al2O3 catalyst is an unprecedent versatile system for gas phase CO2 recycling. Beyond its excellent performance, our switchable catalyst allows a fine control of end-products selectivity.

Carbon dioxide (CO2) is one of the most harmful greenhouse gases and it is the main contributor to climate change. Its emissions have been constantly increasing over the years due to anthropogenic activities. Therefore, efforts are being made to mitigate emissions through carbon capture and storage (CCS). An alternative solution is to close the carbon cycle by utilising the carbon in CO2 as a building block for chemicals synthesis in a CO2 recycling approach that is called carbon capture and utilisation (CCU). Dual Function Materials (DFMs) are combinations of adsorbent and catalyst capable of both capturing CO2 and converting it to fuels and chemicals, in the same reactor with the help of a co-reactant. This innovative strategy has attracted attention in the past few years given its potential to lead to more efficient synthesis through the direct conversion of adsorbed CO2. DFM applications for both post combustion CCU and direct air capture (DAC) and utilisation have been demonstrated to date. In this review, we present the unique role DFMs can play in a net zero future by first providing background on types of CCU methods of varying technological maturity. Then, we present the developed applications of DFMs such as the synthesis of methane and syngas. To better guide future research efforts, we place an emphasis on the connection between DFM physiochemical properties and performance. Lastly, we discuss the challenges and opportunities of DFM development and recommend research directions for taking advantage of their unique advantages in a low-carbon circular economy.