Cooperative carbon capture and steam regeneration with tetraamine-appended metal–organic frameworks

Abstract

Natural gas has become the dominant source of electricity in the United States, and technologies capable of efficiently removing carbon dioxide (CO2) from the flue emissions of natural gas–fired power plants could reduce their carbon intensity. However, given the low partial pressure of CO2 in the flue stream, separation of CO2 is particularly challenging. Taking inspiration from the crystal structures of diamine-appended metal–organic frameworks exhibiting two-step cooperative CO2 adsorption, we report a family of robust tetraamine-functionalized frameworks that retain cooperativity, leading to the potential for exceptional efficiency in capturing CO2 under the extreme conditions relevant to natural gas flue emissions. The ordered, multimetal coordination of the tetraamines imparts the materials with extraordinary stability to adsorption-desorption cycling with simulated humid flue gas and enables regeneration using low-temperature steam in lieu of costly pressure or temperature swings.

Nanoscale cooperative adsorption for materials control

“…1b , inset), reflecting that ~2 CTAB molecules adsorb concurrently. This positive adsorption cooperativity, important for high adsorption efficacy 1 , 6 , 22 and revealed here on nanoparticles, possibly stems from attractive hydrophobic interactions between the alkyl chains of CTA + , as in self-assembled monolayers 23 (Br − contribution is small; see later).…”

CO2 Chemisorption Behavior of Coordination‐Derived Phenolate Sorbents

“…The trend observed in this work may supply an alternative way to regulate the CO 2 chemisorption behavior, including the controlling over the energy requirement in CO 2 desorption, via metal‐ion coordination. Similar strategies have been reported in solid absorbents composed of metal–organic frameworks (MOFs) and polyamines [1d,e] …”

Zinc(ii) and cadmium(ii) amorphous metal–organic frameworks (aMOFs): study of activation process and high-pressure adsorption of greenhouse gases

“…This simple interaction has so far led to a number of nanoporous polymers in which nitrogen-rich functions are incorporated, such as triazine, 65,66 tetrazole, 67 imidazole, 68,69 imide 70 and amines. 42,71 Increased CO 2 adsorption capacity in UPJS-13 (FD) and UPJS-14 (FD) can be explained by an interaction between CO 2 molecules and adsorption sites represented by a lone pair on the azo functional groups located in the molecular structure of the MTA linker. In the case of azo group, the interaction with CO 2 was also conrmed by computational studies, in which the relative binding affinity of CO 2 to the -N]Ngroup using trans-azobenzene as a model system were performed.…”

“…Examples are tetraamineappended MOF Mg 2 (dobpdc) (dobpdc ¼ 4,4 0 -dioxidobiphenyl-3,3 0 -dicarboxylate, S BET ¼ 2880 m 2 g À1 ), which can store up 90 wt% CO 2 (ref. 42) and amine graed silica materials. [43][44][45] In order to avoid CO 2 -intensive energy processes, CO 2 molecules must be captured in porous materials by physisorption as a chemisorption process.…”