Tuning Organic Carbon Dioxide Absorbents for Carbonation and Decarbonation

Abstract

The reaction of carbon dioxide with a mixture of a superbase and alcohol affords a superbase alkylcarbonate salt via a process that can be reversed at elevated temperatures. To utilize the unique chemistry of superbases for carbon capture technology, it is essential to facilitate carbonation and decarbonation at desired temperatures in an easily controllable manner. Here, we demonstrate that the thermal stabilities of the alkylcarbonate salts of superbases in organic solutions can be tuned by adjusting the compositions of hydroxylic solvent and polar aprotic solvent mixtures, thereby enabling the best possible performances to be obtained from the various carbon dioxide capture agents based on these materials. The findings provides valuable insights into the design and optimization of organic carbon dioxide absorbents.

An investigation of carbon dioxide capture by chitin acetate/DMSO binary system

“…Upon bubbling CO2, two peaks emerged at 124.7 and 157.4 ppm, which were ascribed to physically dissolved CO2 in DMSO, and the newly formed alkylcarbonate peak, respectively. The organic alkylcarbonate was consistent with the values reported by Stoddart (Gassensmith et al, 2011), Jessop (Jessop et al, 2005a;Phan et al, 2008) and very recently by Park (Rajamanickam, Kim, & Park, 2015). Therefore, as the carbonation progresses, alkyl carbonate anion is obtained according to the following equation:…”

Chemisorption of air CO2 on cellulose: an overlooked feature of the cellulose/NaOH(aq) dissolution system

“…In the light of the extensively reported ability of DBU to capture CO 2 in the presence of H-donors (Heldebrant et al , 2008Jessop et al 2005;Yang et al 2011;Mizuno et al 2012;Carrera et al 2015;Rajamanickam et al 2015), these observations could be interpreted as indicative of CO 2 interactions with cellulose/NaO-H(aq) along with changes in the dissolved state stability.…”

Inedible saccharides: a platform for CO2 capturing

“…Most of the literature reports focus on the capturing process highlighting the high-energy penalty associated with the regeneration of conventional aqueous amine solvents in comparison with alcohol/SB binary mixtures that suffer from high volatility and corrosiveness, which makes the use of aprotic solvents a reasonable alternative to increase the efficiency of carbon dioxide desorption as they have a lower heat capacity than aqueous based sorbents and a higher vapor pressure as introduced by Park and colleagues, 45 and followed-up by our research group. 28 , 46 , 47 As a matter of fact, the solvation of ions is of great importance when forming CO 2 adducts from neutral solutions.…”

“…Accordingly, cations are well solvated in polar aprotic solvents, while anions are poorly solvated, therefore, this might favour a shift in the equilibrium towards the neutral species and, consequently, p K a values greater than that formed while working in aqueous solutions. 45 …”