Open AccessReversible Ionic Liquids as Double-Action Solvents for Efficient CO2 Capture
Author(s) -
Charles A. Eckert,
Charles L. Liotta
Publication year - 2011
Language(s) - English
Resource type - Reports
DOI - 10.2172/1084025
Subject(s) - ionic liquid , physisorption , chemistry , solubility , solvent , chemisorption , absorption (acoustics) , desorption , aqueous solution , molecule , salt (chemistry) , chemical reaction , ionic bonding , chemical engineering , inorganic chemistry , organic chemistry , materials science , adsorption , ion , catalysis , engineering , composite material
We have developed a novel class of CO{sub 2} capture solvents, Reversible Ionic Liquids (RevILs), that offer high absorption capacity through two modes of capture: chemical reaction (chemisorption) and physical solubility (physisorption). These solvents are silicon containing alkaline compounds such as silylamines that form a liquid salt (ionic liquid) upon reaction with CO{sub 2}. Subsequently, modest elevations in temperature reverse the reaction and yield pure CO{sub 2} for sequestration. By incorporating Si in the molecules we have reduced the viscosity, thereby improving the mass transfer rates of CO{sub 2} absorption/desorption and decreasing the processing costs for pumping the solvent. In this project, we have made systematic changes to the structure of these compounds to improve several physical and thermodynamic properties important for CO{sub 2} capture. Through these structure-property paradigms, we have obtained a RevIL which requires only a third of the energy required by conventional aqueous MEA process for 90% CO{sub 2} capture