Appending Polyamines\non Metal–Organic Frameworks\nas an Efficient Strategy for Selective Removal of H<sub>2</sub>S under\nHumid Conditions

Removal of highly toxic and corrosive hydrogen sulfide\nfrom gas\nflows is of paramount importance for controlling the environment and\nin several industrial processes. This contribution reports a straightforward\nstrategy to engineer sorbents for efficient hydrogen sulfide removal\nunder humid conditions by functionalizing the open metal sites of\nmetal–organic frameworks (MOFs) with polyamines. MIL-101(Cr)\nMOFs were successfully modified with ethylenediamine and tris(2-aminoethyl)amine,\nand the resulting materials were characterized using X-ray diffraction,\nFTIR, NMR, nitrogen sorption, and thermogravimetric analysis (TGA),\nconfirming the functionalization. Although the functionalized MOFs\nexhibited a greater affinity for water compared to the unmodified\nMIL-101(Cr), they efficiently removed H<sub>2</sub>S under humid conditions\nwithout framework degradation, whereas the pristine material did not.\nThis was demonstrated by TGA-MS and elemental analysis and confirmed\nby density functional theory calculations. The developed approach\noffers a promising pathway for the design of advanced sorbents tailored\nfor H<sub>2</sub>S removal in industrial and environmental applications.