Synthesis, characterization, and application of diethylenetriamine functionalized MIL-53(Fe) metal-organic framework for efficient As(V) removal from surface and groundwater

In the last decade, Metal-organic frameworks (MOFs) were utilized to uptake pollutants from water due to their distinctive features such as tunability, high surface area, and ease of functionalization. In the present research, a novel amine-functionalized MIL-DETA-n (n ​= ​DETA molar ratio) was prepared through the impregnation method using diethylenetriamine (DETA) and MIL-53 (Fe) and characterized using SEM, EDX, XRD, FT-IR, and BET analyses. The MIL-DETA-n was used to adsorb As(V) from aqueous media, and adsorption capacity was reached 137.5 ​mg/g. DETA functionalization of MIL-53(Fe) decreased Fe leaching and kept Fe concentration below 0.3 ​mg/L as the maximum contaminant level. The effect of different parameters such as temperature, pH, trace arsenate concentrations, co-existing ions, and reusability was studied. The kinetic and thermodynamic studies demonstrated that adsorption follows the pseudo-second-order model, and the equilibrium data fits with the Langmuir isotherm. For the first time, the MIL-DETA-n was successfully employed to remove arsenic from surfaces and groundwater.