[Removal of Fe(Ⅱ), Mn(Ⅱ), and NH-N by Using -MnO Coated Zeolite].

-MnO/zeolite nanocomposites were prepared with natural zeolite, potassium permanganate, and manganese sulfate by oxidation-reduction precipitation, which were used to simultaneously remove Fe, Mn, and NH-N from groundwater. To investigate the performance and mechanism of Fe, Mn, and NH-N removal from groundwater by -MnO/zeolite nanocomposites, static batch experiments were conducted under different environmental conditions in a zero-oxygen atmosphere using SEM, TEM, Zeta potential, FTIR, and XPS techniques. The experimental results showed that the manganese-oxide-coated natural zeolite was -MnO, and Fe, Mn, and NH-N adsorption on the -MnO/zeolite nanocomposites could be best described with the pseudo-second-order kinetic model and the Langmuir model. In addition, the maximum adsorption capacities of Fe, Mn, and NH-N were calculated to be 215.1, 23.6, and 7.64 mg·g, respectively. The removal mechanism of NH-N from the solutions by zeolite was via the action of ion exchange, and the adsorption and oxidation catalysis of -MnO-coated zeolite were responsible for the removal of Fe and Mn. This research indicates that -MnO/zeolite nanocomposites could be used as highly efficient adsorbents to simultaneously remove Fe, Mn, and NH-N from water.