Advanced techniques for the capturing and separation of CO2 – A review

Abstract

The review was carried out to compare the efficiencies of the advanced and modern techniques for the capturing of CO2 and those (technologies) which are already in place. The ever-growing concern for the need to reduce and eliminate the effects of CO2 in the atmosphere has led to major areas of CO2 capture, over the years, to be explored and applied. Several techniques such as adsorption, absorption, cryogenic separation technique, membrane and a combination of two or more of these techniques were explored to determine which was most effective in the carbon capture process. A combination of the principles of these techniques were explored to determine how they can be applied in the advanced techniques of the CO2 capturing and storage processes, within this new age. Absorption stands out as the most commonly used technique for carbon capture. However, it is energy intensive and depending on the solvent used (i.e., ethanol), can be corrosive to the vessel it is utilized in. The review explored advanced methods for carbon dioxide capture such as the use of ionic liquids, zeolites, molten carbonate fuel cell and integration with several other components that enhance, not only their efficiencies, but also other physio-chemical properties that encourage its advancement. These were explored in the course of writing this review paper. From the review, it was discovered that Ionic liquids, integrated with membranes, enhance selectivity towards efficient CO2 capture. Zeolites occur naturally or are produced synthetically. They comprise of metal ions, are porous and made of certain ligands. They apply the principle of adsorption to remove CO2 and store. Molten carbonate fuel cells operate at high temperatures (usually at 600 ◦C) and have CO2 removal efficiencies of up to 60%. The review paper was, successfully, able to identify some of the major advanced technologies in the process of Carbon capture and the principles, efficiencies and costeffectiveness were described, appropriately. From the literature, molten carbonate fuel cells were the best of the three advanced methods, with high efficiency and operations at high (and varying) ranges of temperature