Addressing the pressing challenge of high energy consumption and solvent waste in the industrial-scale production of metal-organic frameworks (MOFs), we report a rapid, green, and scalable mechanochemical strategy for the mass preparation of the highly efficient CO₂ adsorbent, UTSA-16(Zn). Unlike conventional solvothermal methods, this protocol using zinc acetate and potassium citrate dramatically shortens the synthesis time from 48 hours to just 6 hours. This achieves a remarkable 48-fold enhancement in space-time yield while reducing solvent consumption by approximately 90%. Crucially, we identify that the in-situ accumulation of acidic byproducts during grinding inhibits framework assembly. Precise pH modulation using 0.2 equivalents of triethylamine (TEA) is essential to buffer the reaction environment, preventing defect formation and ensuring high product crystallinity. The resulting material is structurally isomorphous to its hydrothermally synthesized counterpart, possessing a consistent pore environment with a high BET surface area of 817 m²/g. In terms of performance, the mechanochemically derived UTSA-16(Zn) exhibits exceptional CO₂ uptake (3.68 mmol/g at 296 K and 1 atm) and an ultra-high IAST selectivity of 388 for CO₂/N₂ mixtures, driven by a significant difference in isosteric heat of adsorption. Dynamic breakthrough experiments further validate a robust dynamic capacity of 1.94 mmol/g and stable recyclability under simulated flue gas conditions. This work not only provides a practical manufacturing route for UTSA-16(Zn) but also underscores the pivotal role of pH regulation in the green synthesis of advanced porous materials.

Key words: UTSA-16, MOFs, Separation, Mechanochemical Synthesis, Carbon Dioxide Capture