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The water sensitivity HKUST-1, is a critical concern for realizing practical CO 2 capture. Water stability and high CO 2 adsorption are difficult to achieve simultaneously. Mg and piperazinium-based solid ionic liquids (SoILs) were incorporated into HKUST-1 to enhance its water stability and selective CO 2 capture performance, respectively. The eco-friendly route was utilized for the synthesis of bimetallic Mg(x)-HKUST-1, employing water as the sole solvent with stirring and microwave treatment. The SoILs were incorporated into the pore structure of Mg(15)-HKUST-1 by wet impregnation. Among the different ratios of Mg used for the synthesis, 15 % Mg exhibited the highest improvement in CO 2 capacity (5.32 mmol/g) and CO 2 /N 2 selectivity (27) compared to the parent HKUST-1 (CO 2 capacity, 4.2 mmol/g; CO 2 /N 2 selectivity, 17). Once Mg(15)-HKUST-1 was impregnated with 10 % SoIL, the CO 2 capture performance was further improved. In the stability study, 10 % SoIL/Mg(15)-HKUST-1 and Mg(15)-HKUST-1 preserved respectively 92.4 % and 85.3 % CO 2 adsorption capacity after 20 days of exposure to a humid environment (60 % RH) at 298±5 K, an improvement compared to the HKUST-1 (26 %). The CO 2 and N 2 adsorption capacities of HKUST-1, Mg-HKUST-1, and SoIL/Mg-HKUST-1 composite were measured using a volumetric method and characterized using Brunauer-Emmett-Teller (BET) analysis, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). [Display omitted] • Water stable bimetallic HKUST-1 MOF was synthesized by doping Mg. • Piperazine based SoIL was impregnated into bimetallic Mg(15)-HKUST-1 for selective CO 2 capture. • 10 %SoIL/Mg(15)-HKUST-1 exhibited 44 % and 318 % improvement in CO 2 adsorption capacity and CO 2 /N 2 selectivity at 298 K. • 10 %SoIL/Mg(15)-HKUST-1 maintained 92.4 % CO 2 adsorption capacity after 20 days exposure (60 % RH) at 298. [ABSTRACT FROM AUTHOR]

MIL-101(Cr, Mg) is a promising metal organic framework (MOF) considering its moisture, thermal, and chemical stabilities. Piperazine-loaded polyacrylonitrile (PAN)/MIL-101(Cr, Mg) fiber mats were fabricated with different percentages of piperazine (10%, 20%, and 30%) in the polymer solution using an electrospinning technique. The PAN/MIL-101 fiber mats exhibited improved adsorption capacity and selectivity when combined with piperazine because of the improved affinity of CO 2 molecules for the basic amine sites of piperazine. PAN/MIL-101–20% was selected as an optimum fiber mat owing to its high CO 2 adsorption capacity (2.48 mmol/g) and selectivity (38), which are 2.4 and 2.9 times higher than those of the fiber mat without piperazine, respectively. The stability of the PAN/MOF fiber mat in humid air and NO 2 gas and the results of ten adsorption-desorption experiments showed consistent CO 2 capture performance. [Display omitted] • PAN/MIL-101(Cr,Mg) fiber mats with piperazine were fabricated using electrospinning technique • With 20% piperazine, PAN/MIL-101(Cr,Mg) fiber mats showed 2.4 and 2.9 times increase in CO 2 capacity and CO 2 /N 2 selectivity. • PAN/MIL-101(Cr,Mg)-Pz-20% showed a strong stability to humid air and NOx. • Consistent performance observed in CO 2 adsorption (298 K)-desorption (393 K) cycles of PAN/MIL-101(Cr,Mg)-Pz-20%. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) UTSA-16 (Co) was shaped into pellets with diameters of 0.2 mm using activated carbon (AC), silica, and 8% polyvinyl butyral (PVB)/ethanol solution as a binder. A series of AC and silica pellets was prepared with different percentages of the UTSA-16 (Co) MOF. As the percentage of UTSA-16 (Co) increased, the CO 2 adsorption capacity and CO 2 /N 2 selectivity of the AC and silica pellets increased. AC/UTSA-16 (Co)− 30% pellets showed 83% enhancement in CO 2 adsorption capacity and 800% improvement in CO 2 /N 2 selectivity at 298 K compared to the AC pellet. The stability of AC-UTSA-16 (Co) pellets was analyzed by exposing them to SO 2 and NO 2 for 2 days. The performance of AC was further investigated by preparing an AC composite pellet using UTSA-16 (Zn). AC/UTSA-16 (Zn)− 30% pellets showed 75% enhancement in CO 2 adsorption capacity and 1000% improvement in CO 2 /N 2 selectivity than parent AC pellet. CO 2 adsorption–desorption cycles were performed to examine the long-term stability of the pellet composites. The pellets were characterized by scanning electron microscopy (SEM) for particle morphology, thermogravimetric analysis (TGA) for thermal stability, and Brunauer–Emmett–Teller (BET) method for structural properties. • MOF pellets were made with different compositions of MOF, activated carbon, and silica. • AC/UTSA-16 pellets (30%) achieved 76–83% improvement in CO 2 adsorption capacity to the parent AC pellet. • AC/UTSA-16 pellets (30%) showed 700–930% improvement in CO 2 /N 2 selectivity compared to the parent AC pellet • AC/UTSA-16 (Zn) pellets (30%) showed a strong stability to humid air, SOx, and NOx. [ABSTRACT FROM AUTHOR]