Effect of synergistic sorption of Cr(VI) and Mn(II) in aqueous solution using magnetic nanoparticles

Abstract

ABSTRACTIn this study, the effect of synergistic sorption of Cr(VI) and Mn(II) in aqueous solution removal by synthetic magnetic nanoparticles (Fe3O4) was investigated. The results showed that individual removal of Cr(VI) and Mn(II) by Fe3O4 nanoparticles was evidently dependent on pH, and the optimum removal condition for Cr(VI) and Mn(II) was at pH 4 and pH 8, respectively. The removal of Cr(VI) with the pre-treated method was slightly higher than simultaneous method at pH 4. However, the removal of Cr(VI) with simultaneous method was significantly higher than pre-treated method at pH 8 of which the removal percentages were 84.9 and 21.5, respectively. At the same time, for the pre-treated and simultaneous method at pH 8, the equilibrium capacity of Mn(II) on Fe3O4 nanoparticles was changed from 36.8 to 49.7 mg g−1Fe3O4. The XRD patterns after sorption indicated that there is some hematite formation on the Fe3O4 surfaces. Therefore, a redox process could happen in the Cr(VI) sorption on the Fe3O4 nanopa...