Amine-functionalized metal-organic framework/graphene oxide nanocomposite for the removal of Direct Red 23 from water

Herein, MIL-53 (Fe) and MIL-53 (Fe)/graphene oxide (GO) nanocomposite were synthesized and denoted as MIL-C, and MIL-C/GO. The synthesized materials were modified using 3-amino propyl trimethoxy silane (APTMS) (amine-functionalization) with different amounts (0.1, 0.2, and 0.3 mL for preparing MIL-C/NH2(0.1), MIL-C/NH2(0.2), and MIL-C/NH2(0.3), MIL-C/GO-NH2(0.1), MIL-C/GO-NH2(0.2), and MIL C/GO-NH2(0.3), respectively) and characterized. Direct Red 23 (DR23) was used as a model pollutant. The dye adsorption followed a Langmuir isotherm and pseudo-second-order model. The MIL-C/GO and MIL-C/GO-NH2(0.3) showed the adsorption capacity of 1,371 and 4,504 mg/g, respectively. The high removal ability and reusability indicated that the synthesized MIL-C/GO-NH2(0.3) could be as an alternative adsorbent for other organic contaminant with similar chemical structures from aqueous media.