天然黄铁矿除Cr(Ⅵ)中Cr_2S_3物相的发现  

The discovery of Cr_2S_3 phase during the treatment of Cr(Ⅵ) by natural pyrite

作　　者：石俊仙[1] 鲁安怀[2] 陈洁[3] 

机构地区：[1]内蒙古大学化学化工学院,内蒙古呼和浩特010021 [2]北京大学地球与空间科学学院,北京100871 [3]中国地质大学材料科学与工程学院,北京100083

出　　处：《岩石矿物学杂志》2005年第6期539-542,共4页Acta Petrologica et Mineralogica

基　　金：国家重大基础研究前期研究专项(2001CCA02400);国家自然科学基金资助项目(49672097)

摘　　要：利用天然黄铁矿处理含Cr(Ⅵ)废水实验,在反应中与反应后黄铁矿表面和胶体沉淀物中明显出现Cr2p的XPS能谱峰,能拟合出574.7～575.1eV、576.6～576.9eV和578.2～578.7eV3个峰位,分别代表Cr2S3、Cr2O3和CrO3物相。在实验过程中新发现Cr2S3沉淀物相,表明在常温常压下的水溶液介质中也能产生铬的硫化物物相。充分利用这些含铬物相,能使天然黄铁矿包括天然磁黄铁矿在还原Cr(Ⅵ)的同时,无需加碱就可将Cr(Ⅲ)沉淀转移到胶体沉淀物中,处理后的上清液中全Cr含量低于1.5mg/L的国家允许排放标准。天然黄铁矿自身溶解出的重金属含量很低,不影响处理后的出水水质。开发利用Cr2S3等含铬沉淀物相,便于推广应用天然黄铁矿和磁黄铁矿还原Cr(Ⅵ)同时沉淀Cr(Ⅲ)的一步法除铬新工艺。This paper made an experimental study of Cr（ Ⅵ ）-bearing wastewater treated by natural pyrite. XPS peaks of Cr2p appar- ently appeared on the pyrite surface and colloidal precipitates during and after the reaction, which can be fitted into three peaks at different binding energies of 574.7-575.1 eV, 576.6-576.9 eV and 578.2-578.7 eV. The relative peaks represent the phases of Cr2S3, Cr2O3 and CrO3, respectively. The precipitate phase of Cr2S3 was found for the first time in this experiment. The results show that the phase of chromium-bearing sulfides can be produced in aqueous media under the conditions of room temperature and normal ambient pressure. Taking full advantage of this chromium-bearing sulfide phase, we can utilize natural pyrite including pyrrhotite to transfer Cr （ Ⅲ ） precipitates directly into colloidal precipitates without adding base in the process of reducing Cr（ Ⅵ ）. The content of total chromium in the upper treated supernatant is lower than that of the National Standards of Sewage Treatment. The heavy metals dissolved by natural pyrite itself are very low in content so that they don＇ t affect the effluent quality. In order to apply and extend the new technology for one-step treatment of Cr（ Ⅵ ）-bearing wastewater in which Cr （ Ⅵ ） was reduced and Cr （Ⅲ） was precipitated simultaneously by natural pyrite and pyrrhotite, we should exploit and apply chromium-bearing precipitate phase.

关 键 词：天然黄铁矿 含Cr(Ⅵ)废水 重金属 污染治理 Cr2S3物相 XPS分析 

分 类 号：P578.292[天文地球—矿物学] X703[天文地球—地质学]