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硫化亚铁（FeS）普遍存在于厌氧沉积物环境当中，由于其具有吸附性和还原性，在重金属元素的地球化学循环中扮演极其重要的角色。锑（Sb）是一种潜在的有毒致癌重金属元素，厌氧条件下主要以Sb(Ⅲ)的形式存在。研究表明厌氧环境中Sb的地球化学循环与铁硫化物密切相关，然而，FeS对Sb迁移转换机制的影响的相关研究相对较少。本文以实验室制备的FeS为研究对象，测试了其溶解性以及表面形貌。并通过条件实验，考察不同pH、初始FeS、反应时间等因素对吸附Sb的影响，旨在探究厌氧条件下FeS对Sb(Ⅲ)的吸附动力学、吸附等温线以及不同条件下的反应机理。主要的结果和结论归纳如下：（1）采用SEM对实验室制备的FeS进行表征，结果表明合成FeS为纳米粒度颗粒，表面粗糙多孔，结晶度差。稳定性实验表明，FeS对pH具有高度依赖性，酸性条件下能大量溶解，中性至碱性条件下溶解度较小。（2）不同pH条件下FeS与Sb之间的相互作用机制存在差异。中性至碱性条件下，FeS与Sb之间的相互作用主要以吸附反应为主；而酸性条件下，由于FeS大量溶解，两者之间的相互作用主要是FeS的溶解产物与Sb(Ⅲ)结合形成难溶的Sb2S3沉淀。（3）FeS对Sb(Ⅲ)的吸附分为两个阶段：快速吸附阶段和后期缓慢吸附阶段，反应平衡时间为17 h。采用准一级、准二级、Elovich以及W-M模型拟合吸附动力学过程，发现吸附过程符合准二级动力学模型的描述。W-M模型指出吸附只发生在FeS外表面，并未深入到颗粒内部。（4）中性条件下，FeS对Sb(Ⅲ)的最大吸附量为380.3 mg/g，属于单层吸附。Langmiur模型及Temkin模型对等温吸附数据的拟合度很高，分别为0.956、0.969。考虑到实际情况并非Langmiur模型所假设的理想情况，本研究认为Temkin模型能更好的描述FeS对Sb(Ⅲ)的吸附。

In anoxic sulfidic setting, FeS is ubiquitous and is likely to play a crucial role in the geochemical cycle of heavy metals since its adsorption and reduction. Antimony (Sb) is a potentially toxic and carcinogenic heavy metal element, mainly exists in the form of Sb(Ⅲ) under anaerobic conditions. Studies have shown that the geochemical cycle of antimony in anaerobic environment is closely related to iron sulfides. However, limited knowledge is available about the impact of FeS on the geochemical behavior of Sb. In this paper, the solubility and surface morphology of FeS prepared in laboratory were tested. The effects of different pH, initial FeS and reaction time on the adsorption of Sb were investigated through conditional experiments. The purpose was to explore the adsorption kinetics, adsorption isotherm and reaction mechanism of FeS on Sb (III) under anaerobic conditions. The main results and conclusions are summarized as follows:(1) FeS prepared in the laboratory was characterized by SEM. The results showed that the synthesized FeS was nano-sized particles with rough and porous surface and poor crystallinity. Stability experiments showed that the solubility of FeS was highly dependent on pH, that was FeS could soluble in acidic conditions and less soluble in neutral to alkaline conditions.(2) There are differences in the interaction mechanism between FeS and Sb(III) under different pH conditions. Adsorption was the dominant reaction process under neutral to alkaline conditions. While under acidic conditions, the dominant reaction process was precipitation of as sulfide minerals. (3) The process of adsorption can be divided into two stages: fast adsorption stage and slow adsorption stage. The reaction equilibrium time is 17 h. Pseudo-first-order kinetic model, pseudo-second-order kinetic model, Elovich kinetic model and W-M kinetic model were used to fit the adsorption process. The results showed that the pseudo-second-order kinetic model could fit the process well. W-M kinetic model indicated that the adsorption occurred only on the outer surface of FeS and did not penetrate into the interior of the particles.(4) The sorption of Sb(Ⅲ) on the FeS at neutral pH could be well fitted by Langmuir isotherm model and Temkin isotherm model, with the correlation coefficients were 0.956 and 0.969, respectively. The process was single layer adsorption, with a saturated adsorption of 380.3mg/g. Considering that the actual situation was not the ideal situation assumed by Langmuir model, we suggested that Temkin model could better describe the adsorption of Sb (III) by FeS.