Date of Award
M.S. in Engineering Science
Clint W. Williford
Sorbent-based CO2 capture technology is considered as one of the potential scientific techniques for mitigating greenhouse gas emission. Major advantages of sorbent based adsorption are its low regeneration energy coupled with the elimination of corrosion and equipment degradation characteristic of amine based solvent CO2 capture systems which are the preferred industrial methods. Different CO2 capture configurations, processes, and operational parameters for different sorbents were reviewed and summarized. Efficient industrial applications for CO2 capture require that solid sorbents possess an adsorption capacity between 1000-2000µmol/g or more together with a long-term regeneration capacity. Economical consideration necessitates that the cost of CO2 sequestration be less than $10 per ton of CO2. Scientific literature identifies various kinds of sorbents, examples include: activated carbon, modified activated carbon, zeolite, metal-organic framework (MOF) and amine grafted sorbents on silica support. Literature review reveals that amine-grafting process can boost CO2 adsorption on silane sorbent support. The larger surface area of the sorbent support means a greater number of active sites available for grafting which results in a higher CO2 adsorption capacity. The presence of water vapor in the gas stream during grafting and/or during CO2 adsorption can also improve CO2 adsorption of amine-grafted sorbents. Huang reported that MCM-48 silica grafted with 3-aminopropyltriethoxysilane had the greatest CO2 adsorption capacity under anhydrous conditions with 2.30mmol/g sorbent. While Harlick reported that TRI-PE-MCM-41 had the greatest CO2 adsorption capacity under wet conditions with 2.94mmol/g sorbent.
Li, Bingyu, "Co2 Adsorption On Solid Sorbents" (2011). Electronic Theses and Dissertations. 918.
Emphasis: Chemical Engineering