Abstract: Chromium(Ⅵ) is one of the important pollutants in water resources with strong oxidation and migration abilitys. In this paper，the performance of removing chromium(Ⅵ) and its fixation by hematite (α-Fe2O3) was studied. Addition of hematite，adsorption time，chromium(Ⅵ) solution concentration and pH value of the solution would affect the removal of Cr(Ⅵ). Adsorption thermodynamic and kinetic calculations showed that removal of chromium(Ⅵ) mainly depended on adsorption，which was surface adsorption and particle diffusion. Cr(Ⅵ) could be fixed by roasting hematite after adsorption，thus reducing its migration. No desorption occurred with roasting above 800 ℃. XRD，SEM characterization indicated?that no new phase appeared after hematite absorbed Cr(Ⅵ)，instead Cr(Ⅵ) was enclosed in hematite through surface shrinkage and densification. With maximum adsorption capacity of 4.80 mg/g and producing no secondary pollution，hematite is a kind of good environmental friendly mineral materials for fixing pollutants.

Key words: hematite, chromium(Ⅵ), adsorption, roasting, desorption

摘要： 铬(Ⅵ) 是水资源中重要的污染物之一，具有很强的氧化能力和迁移能力。本文对赤铁矿(α-Fe2O3)去除铬(Ⅵ)的性能和固定化能力进行了系统研究。赤铁矿的添加量、吸附时间、铬(Ⅵ)溶液浓度、溶液pH值会影响铬(Ⅵ)的去除效果。吸附热力学和动力学计算均证明了赤铁矿去除铬(Ⅵ)主要是依靠吸附作用，即表面吸附和内部颗粒扩散作用。赤铁矿吸附铬(Ⅵ)后可以通过焙烧实现铬(Ⅵ)的固定，降低其迁移能力，在800 ℃以上焙烧即可实现无解吸。XRD、SEM等测试表征表明，赤铁矿吸附铬(Ⅵ)并将其固定后并不会产生新的物相，而是通过表面收缩、致密化将吸附在表面的铬(Ⅵ)离子包覆在其中，达到固定化的效果。赤铁矿作为优势吸附材料，最大吸附量可达到4.80 mg/g，是无二次污染、可固定化污染物的良好环保型矿物材料。

关键词: 赤铁矿, 铬(Ⅵ), 吸附, 焙烧, 解吸