Hypercrosslinked polymer derived carbon@MIL-100 magnetic material for the enhanced extraction of diclofenac

Abstract

Herein we report for the first time the preparation of a magnetic hybrid carbon@MOF material by combining hypercrosslinked polymer-derived carbon and MIL-100(Fe) MOF. FeCl3, used as catalyst for the synthesis of the benzene-based hypercrosslinked polymer by Friedel-Crafts reaction, was reused for the preparation of a magnetic carbon with a high amount of iron particles, which in turn acted as precursor for the in situ growth of MIL-100(Fe) MOF on the carbon. The effect of the ligand amount and the transformation time in the conversion process was studied by X-ray diffraction and N2 adsorption–desorption isotherms. The developed hybrid material (C-BHCP@MIL-100(Fe)) was evaluated for the extraction of the emerging pollutant diclofenac (DCF) in dispersive mode and the adsorbent was easily retrieved by using an external magnet. The adsorption of DCF by C-BHCP@MIL-100(Fe) fitted the pseudo-second order kinetic model and the Langmuir isothermal model, with a maximum adsorption capacity of 210 mg/g, which is higher than many of the values of DCF adsorption capacity reported in the literature for magnetic adsorbents. The good extraction performance could be attributed to the high surface area and mesoporosity of the obtained hybrid material along with the coexistence of multiple π-π interactions and H-bond interactions between the DCF and the adsorbent. In addition, excellent reusability with a variation of a 2.2 % for 5 consecutive DCF extraction cycles, was obtained, demonstrating the potential of the developed carbon@MOF hybrid material for the removal of DCF and other organic pollutants. The developed synthesis approach can be extended to the preparation of other hypercrosslinked polymer derived carbon@MOFs with great potential for environmental applications.