Chemical immobilization of amino acids into robust metal–organic framework for efficient SO2 removal

Abstract Adsorptive removal of trace SO 2 emissions from flue‐gases can significantly reduce energy and water consumption and minimize the amount of unmanageable waste, however, this remains a great challenge. Herein, we report a universal strategy of chemical immobilization of amino acids into a robust metal–organic framework to enhance deep desulfurization. The grafted amino acid resulted in the formation of pores with compatible pore sizes and created abundant N‐containing moieties for selective SO 2 adsorption. MOF‐808‐His (His = l ‐histidine) exhibited a top‐ranking SO 2 uptake (10.4 mmol g −1 ) with an excellent SO 2 /CO 2 selectivity (90.5) under ambient conditions; furthermore, MOF‐808‐His could be easily regenerated. Breakthrough curves verified its excellent separation performances with water vapor and real flue‐gas compositions. Computational simulations confirmed the vital role of immobilized amino acids in improving the SO 2 capture ability and selectivity. As a proof‐of‐concept, five natural amino acids were immobilized into MOF‐808; all samples displayed improved adsorptive desulfurization performances.