Metal–Organic Framework with Rich Accessible Nitrogen Sites for Highly Efficient CO₂ Capture and Separation

Abstract

A novel microporous metal–organic framework (FJU-44), with abundant accessible nitrogen sites on its internal surface, was constructed from the tetrapodal tetrazole ligand tetrakis­(4-tetrazolylphenyl)­ethylene (H4TTPE) and copper chloride. Notably, the CO2 uptake capacity (83.4 cm3/g, at 273 K and 1 bar) in the activated FJU-44a is higher than most of tetrazolate-containing MOF materials. Particularly, FJU-44a exhibits superior adsorption selectivity of CO2/N2 (278–128) and CO2/CH4 (44–16), which is comparable to some well-known CO2 capture materials. Furthermore, the fixed-bed breakthrough experiment indicates that the postcombustion flue gas flow over a packed column with FJU-44a adsorbents can be effectively separated.

Selective CO2 Sorption Using Compartmentalized Coordination Polymers with Discrete Voids**

“…It should be emphasized that temperature is one of the most critical aspects in common separations, as an increase in energy consumption will affect the viability of industrial efficiency. This fact is particularly relevant considering that apart from CCP‐6 only a few materials are regenerated at room temperature, [28, 29] whereas most of the best performing PCPs/MOFs for these separations require regeneration temperatures of 100–200 °C, especially when CH 4 is part of the target mixture [3–34] …”

“…In addition, the large chemical versatility of these PCPs allows to modify the framework inner space to incorporate different functionalities and promote favourable host‐guest interactions [12, 13] . In this sense, the introduction of specific binding sites for CO 2 , including open‐metal sites [14] or Lewis basic sites, [15–17] has been demonstrated as an efficient solution to separate CO 2 from mixtures of gases [18, 19] …”

Research progress in metal–organic frameworks (MOFs) in CO2capture from post-combustion coal-fired flue gas: characteristics, preparation, modification and applications

“…52 Meanwhile, the open nitrogen atoms on the MOF pore surface can significantly improve the CO 2 absorption due to the multipoint interactions. 53 For example, Ye et al 54 used a tetrapodal tetrazole ligand to synthesize FJU-44, which had a high CO 2 adsorption capacity (83.4 cm 3 g −1 , at 273 K and 1 bar) due to its rich nitrogen content on the surface.…”

Selective CO2 Sorption Using a Compartmentalized Coordination Polymer with Discrete Voids

“…G.M.E. acknowledges funding by the MINECO (Ramón y Cajal Program) and the "Convocatoria 2016 de Ayudas Fundación BBV a Investigadores y Creadores Culturales" (project IN [16]_CBB_QUI_0357). J.C. is grateful to the Generalitat Valenciana (APOSTD/2017/081).…”