Carbon composite membrane derived from MIL-125-NH2 MOF for the enhanced extraction of emerging pollutants

Abstract

[eng] Porous carbon derived from amine-functionalized MIL-125 metal-organic framework (C-MIL-125-NH2) was prepared by carbonization at high temperature under inert atmosphere, and used for adsorption of bisphenol A (BPA) and 4-tert-butylphenol (4-tBP). The obtained carbon showed bimodal porosity and fast extraction of both pollutants in batch conditions following a pseudo-second-order model. The adsorption mechanism was studied by the measurement of zeta potential, and the results suggested that π-π stacking interactions between the carbon material and the phenol molecules probably are the main sorption mechanism. The prepared C-MIL-125-NH2 was incorporated into mechanically stable membranes for flow-through solid-phase extraction of studied phenols prior to HPLC analysis. The hybrid material showed excellent permeance to flow, easy regeneration and good performance for the simultaneous enrichment of mixtures of BPA and 4-tBP, facilitating their determination when present at low concentration levels.