Revealing an unusual temperature-dependent CO₂ adsorption trend and selective CO₂ uptake over water vapors in a polyamine-appended metal–organic framework

Abstract

Heavily tetraethylenepentamine (tepa)-functionalized Mg2(dobpdc) showed an unusual increase in CO2 uptake on increasing the temperature and selective adsorption of CO2 over water vapors.

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

“…The CO2 -capture properties can further be tuned by varying the appended diamine, leading to adsorbents with remarkable potential for CO2 capture from coal flue gas emissions (Fig. 1B) (28)(29)(30)(31) and even NGCC emissions (32).…”

Understanding Correlation Between CO2 Insertion Mechanism and Chain Length of Diamine in Metal‐Organic Framework Adsorbents

“…Each day, the MeOH was decanted and pure MeOH was added to the vial. Elemental analysis (%) calcd for C 16 O) (1-en): 1 (150 mg, 0.47 mmol) was dried in a 100 mL single neck round-bottom Schlenk flask under vacuum overnight. While maintaining the vacuum condition, the flask was placed in 250°C mantle for 30 min and then was cooled to room temperature.…”

“…[15] Polyamines were also evaluated to improve gas adsorption, thus revealing the relationship between loading amounts and adsorption steps, as well as the robustness of the framework under humid conditions. [16] Nonetheless, despite many attempts to post-synthetically modify adducts with bifunctional ligands, the number of carbons between the nitrogen atoms in a diamine ligand has been restricted to 2-3 carbons. While it is generally assumed that lengthy alkyl ligands inhibit the access to binding sites beyond a certain limit, the influence of the distance between functional groups on the CO 2 adsorption properties or mechanism is yet to be verified.…”

Shaping and silane coating of a diamine-grafted metal-organic framework for improved CO2 capture

“…Its adsorption and desorption behaviors can be modulated by selecting the appropriate amine structure [24][25][26][27][28] . To improve the structural durability of the MOFs under humidification conditions, cyclic diamines or polyamines have been grafted onto the open metal sites of the Mg 2 (dobpdc) platform 29,30 . Coating the platforms with hydrophobic polymers also enhanced the structural stability in the presence of moisture 31 .…”

“…Particularly, spray drying provides a cost-effective, rapid, and scalable method to continuously fabricate the shaped materials 34 . Because diamine-grafted Mg 2 (dobpdc) compounds have been extensively explored due to their exceptional CO 2 adsorption capacities for post-combustion capture processes [16][17][18][19][20]24,25,[27][28][29][30][31]35,36 , shaping of the MOF powders is important to increase their processibility and mechanical strength for real-world CO 2 capture applications 37,38 . Furthermore, to overcome the intrinsic limitations of pristine shaped MOFs such as CO 2 adsorption capacity and structural stability under humid conditions, their postsynthetic modifications are required but nearly unexplored.…”