Large-scale synthesis of ZIF-67 and highly efficient carbon capture using a ZIF-67/glycol-2-methylimidazole slurry.

New approaches and materials for inexpensive carbon capture are important areas of research. Herein, we report a new material (i.e., zeolitic imidazolate framework-67 (ZIF-67)/glycol-2-methylimidazole (mIm) slurry) that can be used to capture CO 2 similar to a liquid absorbent, and ZIF-67 was synthesized on a pilot scale. This flowable slurry was formed by suspending ZIF-67 in a glycol–mIm solution. The results from the gas-–slurry equilibrium experiments indicate that this method provides a more efficient approach for the low cost capture of CO 2 compared to conventional technologies. The selectivities for CO 2 /H 2 , CO 2 /N 2 , and CO 2 /CH 4 were 1409, 723, and 222, respectively. The apparent solubility of CO 2 in the slurry was 1.3 mol L −1 , and the sorption enthalpy was only −33 kJ mol −1 at 1 bar and 303.2 K. To simulate an actual separation process for carbon capture using the ZIF-67/glycol–mIm slurry, a series of column breakthrough tests were performed in a stainless steel bubbling column to investigate the influence of temperature, ZIF-67 mass fraction in the slurry, feed gas flow rate, and composition. The slurry was completely regenerated via helium purging and heating at 323–343 K. The CO 2 capture ability of the regenerated slurry was the same as that of the fresh slurry, even after 10 adsorption/desorption cycles. [ABSTRACT FROM AUTHOR]