Mass Transfer, Mechanism, and Diffusion on CO2 Adsorption

This chapter presents an in-depth exploration of the mechanisms, mass transfer, and diffusion central to CO₂ adsorption, an essential process for the development of effective materials for carbon capture and storage. CO₂ adsorption onto solid adsorbents is governed by complex molecular interactions influenced by structural characteristics, surface chemistry, and environmental factors. The chapter begins by examining core adsorption mechanisms, including physisorption and chemisorption, and explores how these interactions impact CO₂ binding affinity, selectivity, and adsorption energy requirements. A detailed analysis of mass transfer processes follows, focusing on the movement of CO₂ molecules from the bulk phase to the adsorbent surface, with special attention to macropore, mesopore, and micropore diffusion pathways. Factors such as pore size, geometry, and surface modifications about their effects on diffusion within porous materials are discussed.