(上海大學(xué) 材料科學(xué)與工程學(xué)院，省部共建高品質(zhì)特殊鋼冶金與制備國家重點(diǎn)實(shí)驗(yàn)室，
上海市鋼鐵冶金新技術(shù)開發(fā)應(yīng)用重點(diǎn)實(shí)驗(yàn)室，上海200444)
摘 要: 在FeCl3-HCl-H2O體系中研究低冰鎳的界面氧化反應(yīng)和反應(yīng)產(chǎn)物的組成及形貌，考查氧化劑濃度和反應(yīng)溫度對于低冰鎳中不同礦相氧化反應(yīng)的影響。利用拉曼光譜、金相顯微鏡、XRD、SEM和EDS等手段對界面產(chǎn)物進(jìn)行表征。采用第一性原理對低冰鎳中主體硫化物礦相的晶體和電子結(jié)構(gòu)進(jìn)行計(jì)算。結(jié)果表明：低冰鎳中合金相最容易氧化浸出，Cu5FeS4比Fe5Ni4S8優(yōu)先氧化生成硫單質(zhì)；固體產(chǎn)物多孔單質(zhì)硫覆蓋了未反應(yīng)的低冰鎳表面。第一性原理計(jì)算結(jié)果顯示，Cu5FeS4和Fe5Ni4S8礦相氧化活性位點(diǎn)都是鐵原子，并且金屬與硫的化學(xué)鍵有明顯的共價(jià)鍵特征；硫化物礦相中過渡金屬原子的氧化優(yōu)先順序依次為：Cu5FeS4礦相中(Fe)＞Fe5Ni4S8礦相中(Fe)＞Fe5Ni4S8礦相中(Ni)＞Cu5FeS4礦相中(Cu)。
關(guān)鍵字: 低冰鎳；界面反應(yīng)；氧化分解；第一性原理計(jì)算；鎳黃鐵礦
（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
