The preparation of a novel iron/manganese binary oxide for the efficient removal of hexavalent chromium [Cr(<scp>vi</scp>)] from aqueous solutions
Chuanxi Yang, Ju Tiantian, Xiaoning Wang, Yujia Ji, Yang Cheng, Haojie Lv, Ying Wang, Wenping Dong, Feng Dang, Xifeng Shi, Weiliang Wang, Yuqi Fan
Abstract
and isoelectric point was observed at pH value of 4.81. The removal of Cr(vi) was chosen as a model reaction to evaluate the adsorption capacity of the Fe-Mn binary oxide adsorbent, indicating that the Fe-Mn binary oxide adsorbent showed high adsorption performance (removal rate = 99%) and excellent adsorption stability (removal rate > 90% after six rounds of adsorption). The adsorption behavior of the Fe-Mn binary oxide was better represented by the Freundlich model (adsorption isotherm) and the pseudo-second-order model (adsorption kinetic), suggesting that the adsorption process was multi-molecular layer chemical adsorption. The possible adsorption mechanism of the Fe-Mn binary oxide for the removal of Cr(vi) included the protonation process and the electrostatic attraction interactions.