The Effect of Proton and Arsenic Concentration on As(III) Removal by Hematite and Kaolin Complexes

With the intensification of human activities, arsenite (As(III)) pollutant from the soil and ground water has been a threat to human health, and the problem gradually becomes the focus of attention. In this study, the effects of several environment factors on As(III) removal ability of complex minerals are determined through the analysis of mineralogical characteristics of the complex synthesis of hematite and kaolin, using X-ray diffraction, Fourier transform infrared, and specific surface area. In the results, the XRD patterns of hematite and kaolin complexes indicate that the loading covers up some characteristic peaks of minerals in kaolin, which can be that hematite loading decrease the order of structure for some minerals. With increasing Fe content, the hydroxyl sites gradually increase, therefore strengthening the As(III) removal ability of complexes. With increasing the As(III) concentration, the removal ratios of kaolin on As(III) almost keep unchanged and that of complexes show no obvious regularity. However, with the pH increasing, the removal ratios of all samples keep increasing. Furthermore, the increasing of As(III) concentration and pH both improve As(III) removal amount significantly, especially for As(III) concentration. In addition, there is no forming of new mineral through it as observed by XRD. Therefore, hematite loading can promote the As(III) removal on kaolin through adsorption in different environments, which can provide a better method for the remediation of arsenic pollution.