A millimeter-sized negatively charged polymer embedded with molybdenum disulfide nanosheets for efficient removal of Pb(Ⅱ)from aqueous solution

Molybdenum disulfide(MoS_(2))has excellent trapping ability for lead ions whereas its micro-/nanoscale size has greatly impeded its practical applications in the flow-through systems.Herein,a millimetersized nanocomposite MoS_(2)-001 was synthesized for Pb^(2+)removal by loading MoS_(2) nanosheets into a polystyrene cation exchanger D-001 by a facile hydrothermal method.The proposed structure and adsorption mechanism of MoS_(2)-001 was confirmed by the scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectro scopy(XPS)analysis.The nanocomposite showed outstanding adsorption capacity and rapid adsorption kinetic for Pb^(2+)removal,and the adsorption behavior followed the Langmuir adsorption model and pseudo-firstmodel kinetic model.Pb^(2+)uptake by MoS_(2)-001 still maintains a high level even in the presence of extremely highly competitive ions(Ca(Ⅱ)and Mg(Ⅱ)),suggesting its high selectivity for Pb^(2+)adsorption.Besides,the fixed-bed column experiments further certified that MoS_(2)-001 is of great potential for Pb^(2+)removal from the wastewater in practical engineering applications.Even more gratifying is that the exhausted MoS_(2)-001 can be regenerated by NaCl-EDTANa_(2) solution without any significant adsorption capacity loss.Consequently,all the results indicated that MoS_(2)-001 is a promising candidate adsorbent for lead-containing wastewater treatment.