Enhancement tetracycline adsorption by amino/nitro-functionalized MIL-126(Fe) adsorbent based on the ligand installation method
MIL-126(Fe) shows great potential for aqueous phase drug adsorption due to its permanent porosity and easy modification. Herein, we utilized the ligand installation method to introduce two ligands, 2-amino terephthalic acid (NH 2 -BDC) and 2-nitro terephthalic acid (NO 2 -BDC), into MIL-126(Fe) to prepare MIL-126(Fe)-NH 2 and MIL-126(Fe)-NO 2 , respectively. Various analytical tools were used to confirm the successful installation of the 1, 4-phthalic acid (BDC) series of ligands, as well as the successful introduction of amino (-NH 2 ) and nitro (-NO 2 ) groups. The presence of both -NH 2 and -NO 2 groups improved the adsorption of TC by the adsorbent material, with -NH 2 groups having a stronger influence on the enhancement. The experimental results indicated that MIL-126(Fe)-NH 2 had the highest adsorption performance at the optimal pH of 7, achieving a static adsorption capacity of 326.5 mg/g, which was about twice the adsorption capacity of the original MIL-126(Fe). X-ray photoelectron spectroscopy (XPS) determined that the adsorption of TC by MIL-126(Fe)-NH 2 relies mainly on π-π interaction and Fe-N coordination bonds. Furthermore, the higher adsorption capacity of MIL-126(Fe)-NH 2 can be attributed to the O-H⋯N hydrogen bonds interaction between -NH 2 and the phenolic hydroxyl group (Ph-OH) in the TC molecule.
危险品化学品经营许可证（带存储）