Design and development of amine functionalized iron based metal organic frameworks for selective fluoride removal from water environment

Metal organic frameworks (MOFs) play a crucial role in adsorption method owing to its larger surface area and high porosity. In this work, a trivalent metal ion namely iron (Fe3+) fabricated benzene-1,4-dicarboxylic acid (BDC) and amine functionalized BDC namely 2-aminobenzene-1,4-dicarboxylic acid (ABDC) which gives Fe@BDC and Fe@ABDC based metal organic frameworks (MOFs) for selective fluoride removal. The prepared Fe@BDC and Fe@ABDC MOF composites were acquiring the enhanced defluoridation capacities (DCs) of 4.90 and 4.92 mg g(-1) towards fluoride adsorption. The synthesized Fe@BDC and Fe@ABDC MOF composites were portrayed by FTIR, TGA, SEM, BET, EDAX, XPS and XRD analysis. The responsible parameters towards defluoridation process viz., contact time; solution pH, initial fluoride concentration, adsorbent dosage, interfering anions and temperature were explored by batch level. The adsorption isotherms, kinetics and thermodynamic parameters were investigated for Fe@BDC and Fe@ABDC MOF composites towards fluoride adsorption. The fluoride adsorption mechanism of Fe@BDC and Fe@ABDC MOF composites was discussed in detail. The applicability of field test and recyclability of Fe@BDC and Fe@ABDC MOF composites were also explored.