The third review I contributed to during my time in Kaust is finally available online, published in Chemical Engineering Journal. This time, it is not dealing on materials design, but on CO2 capture from low concentration mixtures. I believe this article written with all the expertise and conviction of my friend and ex colleague Dr. Youssef Belmabkhout will help people understanding more the little details driving the CO2 sorption properties and making one material random, interesting, or even suitable for industrial use…
About the paper: Low concentration CO2 capture using physical adsorbents: Are metal–organic frameworks becoming the new benchmark materials?
• A deep analysis on low concentration CO2 removal using physical adsorbents is proposed.
• In-depth understanding of what are the crucial criteria for materials to be used in CO2 capture.
• MOFs have valuable assets vs. benchmark materials such as zeolites.
• High porosity is not necessarily important for traces and low CO2 concentration capture.
• The uniformity of energetic adsorption sites is not a critical parameter for traces CO2 capture.
The capture and separation of traces and concentrated CO2 from important commodities such as CH4, H2, O2 and N2, is becoming important in many areas related to energy security and environmental sustainability. While trace CO2 concentration removal applications have been modestly studied for decades, the spike in interest in the capture of concentrated CO2 was motivated by the need for new energy vectors to replace highly concentrated carbon fuels and the necessity to reduce emissions from fossil fuel-fired power plants. CO2 capture from various gas streams, at different concentrations, using physical adsorbents, such as activated carbon, zeolites, and metal–organic frameworks (MOFs), is attractive. However, the adsorbents must be designed with consideration of many parameters including CO2 affinity, kinetics, energetics, stability, capture mechanism, in addition to cost. Here, we perform a systematic analysis regarding the key technical parameters that are required for the best CO2 capture performance using physical adsorbents. We also experimentally demonstrate a suitable material model of metal organic framework as advanced adsorbents with unprecedented properties for CO2 capture in a wide range of CO2 concentration. These recently developed class of MOF adsorbents represent a breakthrough finding in the removal of traces CO2 using physical adsorption. This platform shows colossal tuning potential for more efficient separation agents and guide researchers on the crucial criteria to be considered in the development of adsorbents for traces and low concentration CO2 capture.