Typical MOFs-derived nanoporous carbon: Insight into structures, properties and Pb(II) adsorption mechanism

A series of nanoporous carbon (NC) materials were synthesized by direct carbonization of traditional metal organic frameworks (MOFs) including copper-based (HKUST-1), nickel-based (Ni-MOF), zinc-based (ZIF-8), zirconium-based (UiO-66) and iron-based (Fe-BTC) for the removal of Pb(II) from simulated waste water. The physical and chemical characteristics before and after adsorption were thoroughly investigated by Fourier transforms infrared spectroscopy (FTIR), X-Ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption analyses. The adsorption kinetics and isothermal thermodynamic properties and the effects of five central different cations on the removal of Pb(II) were compared. The adsorption kinetics were well described by the quasi-second-order model and the adsorption isotherm consistent with the Langmuir equation. The adsorption process of Pb (II) is feasible, spontaneous, endothermic and reusable on the five nanoporous carbons. Among them, Fe-BTC-NC showed the best adsorption performance for Pb (II), and the maximum adsorption capacity was 479.93 mg/g. This work highlights the applications of MOFs derived nanocarbon in heavy metal contaminated water treatment and offers a facile method for the design of novel nanocarbon materials.