Hexavalent Chromium (Cr(VI)) in water is a public health concern and has been a challenging research subject in environmental field for many years. Herein, a novel composite material consisting of amorphous iron sulfides supported on hydrotalcites (FeS/HTs) was synthesized by “calcination-reconstruction-calcination” process, which enables homogeneous distribution of iron and sulfur on the surface of hydrotalcites (HT). The composite (mass ratio of FeS/HT was 1/2) could effectively remove over 98% of Cr(VI) within 10 min. A pseudo-second-order kinetic model and a Langmuir isotherm model were well fitted the sorption data with a maximum removal capacity of 206.2 mg/g. The superior adsorption capacity of FeS/HTs could be attributed to the combination of the advantages of abundant adsorption sites on HT and powerful reduction properties of iron sulfides. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis suggested the adsorbed Cr(VI) on the surface and interlayer of FeS/HTs had been reduced to Cr(III) by reductant iron and sulfur. This study demonstrated that FeS/HTs has potential application prospects in Cr(VI) removal.

水中的六价铬（Cr（VI））是一个公共卫生问题，多年来一直是环境领域中一个充满挑战的研究课题。在此，通过“煅烧-重构-煅烧”工艺合成了由负载在水滑石上的无定形硫化铁组成的新型复合材料，该方法能够使铁和硫均匀地分布在水滑石（HT）的表面上。复合材料（FeS / HT的质量比为1/2）可在10分钟内有效去除98％以上的Cr（VI）。拟二级动力学模型和Langmuir等温线模型很好地拟合了吸附数据，最大去除量为206.2 mg / g。FeS / HTs的超强吸附能力可归因于HT上丰富的吸附位和硫化铁的强大还原性能的优势。X射线衍射（XRD）和X射线光电子能谱（XPS）分析表明，FeS / HTs的表面和中间层吸附的Cr（VI）已被还原剂铁和硫还原为Cr（III）。这项研究表明，FeS / HTs在去除Cr（VI）中具有潜在的应用前景。