(上海大学 材料科学与工程学院，省部共建高品质特殊钢冶金与制备国家重点实验室，
上海市钢铁冶金新技术开发应用重点实验室，上海200444)
摘 要: 在FeCl3-HCl-H2O体系中研究低冰镍的界面氧化反应和反应产物的组成及形貌，考查氧化剂浓度和反应温度对于低冰镍中不同矿相氧化反应的影响。利用拉曼光谱、金相显微镜、XRD、SEM和EDS等手段对界面产物进行表征。采用第一性原理对低冰镍中主体硫化物矿相的晶体和电子结构进行计算。结果表明：低冰镍中合金相最容易氧化浸出，Cu5FeS4比Fe5Ni4S8优先氧化生成硫单质；固体产物多孔单质硫覆盖了未反应的低冰镍表面。第一性原理计算结果显示，Cu5FeS4和Fe5Ni4S8矿相氧化活性位点都是铁原子，并且金属与硫的化学键有明显的共价键特征；硫化物矿相中过渡金属原子的氧化优先顺序依次为：Cu5FeS4矿相中(Fe)＞Fe5Ni4S8矿相中(Fe)＞Fe5Ni4S8矿相中(Ni)＞Cu5FeS4矿相中(Cu)。
关键字: 低冰镍；界面反应；氧化分解；第一性原理计算；镍黄铁矿
（Shanghai Key Laboratory of Advances Ferrometallurgy, State Key Laboratory of Advanced Special Steel,
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China）
Abstract:The interfacial reactions on low nickel matte in the FeCl3-HCl-H2O solution were investigated, and the composition and morphology of the solid products over the nickel matte were characterized by Raman spectroscopy, optical microscopy, XRD, and SEM with EDS. The structural and electronic properties of bornite (Cu5FeS4) and pentlandite (Fe5Ni4S8) existing in low nickel matte were studied using first principle calculation. The experimental results show that FeNi3 is the most favorable to be oxidized and leached out in the low nickel matte, and the oxidative dissolution of Cu5FeS4 is more preferable to that of Fe5Ni4S8. The solid sulfur with a lot of non-through holes, as one product of the oxidation reactions, covers the surface of the bulk matte and likely retards the matte leaching process. The feasibility of the oxidation process can be enhanced by the high operation temperature. Furthermore, the oxidation of the Fe sites for both Cu5FeS4 and Fe5Ni4S8 is the most favorable according to the calculated total and partial density of state, and the oxidation activity for the elements in Cu5FeS4 and Fe5Ni4S8 decreases in the order of Fe in Cu5FeS4＞Fe in Fe5Ni4S8＞Ni in Fe5Ni4S8＞Cu in Cu5FeS4, which are in good agreement with the experimental results.
Key words: low nickel matte; interface reaction; oxidative dissolution; first principle calculation; pentlandite
