This paper reports the development of a robust microporous aluminum tetracarboxylate framework, MIL-120(Al)-AP, which exhibits high CO2 uptake (1.9 mmol g-1 at 0.1 bar, 298 K). In situ Synchrotron X-ray diffraction and Monte Carlo simulations reveal that the structure offers a favorable CO2 capture configuration with a high density of μ2-OH groups and accessible aromatic rings. The MOF shows moderate host-guest interactions (Qst = −40 kJ mol−1), suggesting a low energy penalty for full regeneration. An environmentally friendly, ambient pressure synthesis route using inexpensive raw materials is developed for kilogram-scale production, with the MOF shaped into millimeter-sized beads using inorganic binders. Breakthrough experiments validate its efficient CO2/N2 separation ability, and operando IR studies indicate kinetically favorable CO2 adsorption over water. A techno-economic analysis estimates a production cost of approximately $13 kg−1, making MIL-120(Al)-AP an excellent candidate for industrial-scale CO2 capture processes.This paper reports the development of a robust microporous aluminum tetracarboxylate framework, MIL-120(Al)-AP, which exhibits high CO2 uptake (1.9 mmol g-1 at 0.1 bar, 298 K). In situ Synchrotron X-ray diffraction and Monte Carlo simulations reveal that the structure offers a favorable CO2 capture configuration with a high density of μ2-OH groups and accessible aromatic rings. The MOF shows moderate host-guest interactions (Qst = −40 kJ mol−1), suggesting a low energy penalty for full regeneration. An environmentally friendly, ambient pressure synthesis route using inexpensive raw materials is developed for kilogram-scale production, with the MOF shaped into millimeter-sized beads using inorganic binders. Breakthrough experiments validate its efficient CO2/N2 separation ability, and operando IR studies indicate kinetically favorable CO2 adsorption over water. A techno-economic analysis estimates a production cost of approximately $13 kg−1, making MIL-120(Al)-AP an excellent candidate for industrial-scale CO2 capture processes.