Enhanced arsenic removal from water by a bimetallic material ZrOx-FeOx with high OH density

Arsenic in groundwater for human consumption has negative effects on human's health worldwide. Due to the above, it is essential to invest in the development of new materials and more efficient technology for the elimination of such priority contaminants as arsenic. Therefore, in the present work, it was synthesized an amorphous hybrid material ZrOx-FeOx with a high density of OH groups, to improve the arsenic adsorption capacity of iron (FeOx) and zirconium (ZrOx) that makes up the bimetallic oxyhydroxide. The spectra of FT-IR and pK_a's distribution suggest that in the synthesized binary oxides, a new union between the two metallic elements is formed by means of an oxygen (metal-O-metal). In addition, TEM profiles suggest that there are chemical interactions between both metals since no individual particles of iron oxide and zirconium oxide were found. According to the results, the adsorption capacity of the ZrOx-FeOx material increases 4.5 and 1.4 times with respect to FeOx and ZrOx, respectively. At pH 6, the maximum adsorption capacity was 27 mg g^-1, but at pH greater than 7, the arsenic adsorption capacity onto ZrOx-FeOx decreased 66%. Graphical Abstract.