Role of Amine Structure on Carbon Dioxide Adsorption from Ultradilute Gas Streams such as Ambient Air

Abstract

A fundamental study on the adsorption properties of primary, secondary, and tertiary amine materials is used to evaluate what amine type(s) are best suited for ultradilute CO(2) capture applications. A series of comparable materials comprised of primary, secondary, or tertiary amines ligated to a mesoporous silica support via a propyl linker are used to systematically assess the role of amine type. Both CO(2) and water adsorption isotherms are presented for these materials in the range relevant to CO(2) capture from ambient air and it is demonstrated that primary amines are the best candidates for CO(2) capture from air. Primary amines possess both the highest amine efficiency for CO(2) adsorption as well as enhanced water affinity compared to other amine types or the bare silica support. The results suggest that the rational design of amine adsorbents for the extraction of CO(2) from ambient air should focus on adsorbents rich in primary amines.

Stability of amine-based hollow fiber CO2 adsorbents in the presence of NO and SO2

“…This capacity loss is suggested to be mainly due to the deactivation of secondary amine groups as a result of non-desorbed SO 2 , which was strongly bonded to the fiber adsorbents. The other possible reason for this capacity loss could be due to the presence of some propylamine impurities in MAPS silane [41,42]. Correspondingly, the deactivation of primary amine impurities upon exposure to SO 2 would lead to the loss of capacity as well.…”

“…In addition to amine loading, the variation of water adsorption capacity influences the amine efficiency as well. Compared to CA-S-MAPS in this work, CA-S-APS, with a higher amine loading, includes more hydrophilic amine groups and likely adsorbs more water than CA-S-MAPS [41]. Therefore, the Experimental procedure of cyclic adsorption-desorption tests.…”

Tailoring amine functionalized hybrid ceramics to control CO2 adsorption

“…In the case of grafting APTES on silica surfaces both effects were observed in literature, decreasing [23] and increasing hydrophilicity [42] compared to that of the unmodified silica, depending on the conditions during functionalization. This indicates that not only the influence of the aminopropyl group on the surface characteristics is important for the water uptake but also the cross-linked structure.…”

Reusable fluorocarbon-modified electrospun PDMS/PVDF nanofibrous membranes with excellent CO 2 absorption performance

“…As a result, CO 2 capture has attracted a large amount of research attention. Various methods of CO 2 capture [1,2], including adsorption [3][4][5][6][7][8], absorption [9][10][11][12][13][14], chemical looping [15,16], membrane processing [17][18][19][20][21][22], and cryogenic distillation [23], have been developed in recent years. The use of membrane contactors [24,25] is a CO 2 capture technique that combines gas absorption and membrane processing, as shown in Scheme 1.…”