A review on clay exfoliation methods and modifications for CO2 capture application

Carbon capture, utilization, and storage techniques are required to address concerns related to global warming resulting from the rising atmospheric CO2 concentration. Currently, amine-based solvents are commonly used for post-combustion CO2 capture. The amine-based (liquid) sorption technology has numerous disadvantages including the perilous by-products and a high-energy prerequisite for their regeneration. Thus, extensive research is ongoing worldwide to develop cost-effective, sustainable, environmentally friendly, and effective sorbents for post-combustion CO2 capture. The distinctive features of clay-based materials make them particularly promising for CO2 adsorption. This critical review explores the current technology, adsorbents, and challenges associated with CO2 capture and finding answers in exploring exfoliated clay-based adsorbents as porous, high-surface area, inexpensive, efficient, and compatible materials for CO2 capture. Specifically, the review narrates a summary of various procedures useful for clay exfoliation and discusses a variety of chemical, inorganic, and organic modifications for designing exfoliated clay-based nanocomposites for CO2 capture. Further, the review touches upon various practical ways to prepare exfoliated clay-based composites, as membranes, aerogels, and nanofluids, for CO2 capture.