Carbon dioxide (CO₂) is a "greenhouse gas" because of its ability to trap solar radiation and keep it confined to the atmosphere, leading to global temperature rise and consequently global climate change, which is one of the major challenges of our time, due to its catastrophic impacts on humans and the environment. To mitigate the effects of CO₂ on global climate change, several initiatives have been taken to address emission reductions, including the 1992 United Nations Framework Convention on Climate Change in Brazil, the 1997 Kyoto Protocol in Japan, the 2009 Copenhagen Accord, signed in Denmark, and the 2015 Paris Agreement, which was a milestone global pact adopted by nearly every country in the world. Its aim is to cap the global temperature rise during this century to a maximum of 2 ^oC, or more precisely to 1.5 ^oC (2.7 ^oF), above the pre-industrial temperature level.

The prime focus of this special issue is on CO₂ capture and utilization. There are several processes for CO₂ capture from a point source, including pre-combustion, post-combustion and oxy-combustion technologies, which have been widely investigated by the academic community and industry from fundamentals to more advanced innovations and applications. There are also increasing potential developments in the direct air capture (DAC) processes, which aim at the removal of CO₂ from the atmosphere. Recent advances in CO₂ capture are leading to the development of more robust processes, including CO₂ absorption and adsorption, solvents and sorbents regeneration, membrane and cryogenic separations, and CO₂ preparation for subsequent utilization or sequestration.

The CO₂ captured can be converted to mineral carbonates or used in food processing, beverages, and urea, or in the production of diethyl carbonate, which can serve as a fuel additive or solvent for lithium batteries. CO₂ can also be processed to produce high-value chemicals, such as potassium or sodium bicarbonate nanomaterials or fuels, including methane, methanol, gasoline, and jet fuels. These could be achieved through thermo-catalytic, photo-catalytic, or electro-catalytic CO₂ conversions. Due to the very stable activity of the CO₂, however, these processes are energy intensive, leading to high capital and operating expenditures. Nonetheless, the energy required could be partially or completely produced via green sources, such as solar, wind, or green hydrogen, which could be a sustainable solution for the CO₂ conversion.

This special issue will cover different topics on CO₂ capture and utilization. Potential topics include, but not limited to the following:

• Chemical CO₂ capture.

• Physical CO₂ capture.

• New advances in CO₂ capture

• Use of renewables in CO₂ capture.

• Techno-economic Analysis (TEA) of the CO₂ capture.

• Life-Cycle Analysis (LCA) of the CO₂ capture.

• Thermo-catalytic CO₂ conversion

• Photo-catalytic CO₂ conversion

• Electro-catalytic CO₂ conversion

• New advances in CO₂ conversion.

• Use of renewables in CO₂ conversion.

CO2 capture;Physical solvents;Chemical solvents;Solid sorbents;CO2 conversion;thermo-catalytic conversion;photo-catalytic conversion;electro-catalytic conversion