(1. 華北理工大學(xué) 礦業(yè)工程學(xué)院，唐山 063009；
2. 河北省礦業(yè)開發(fā)與安全技術(shù)重點(diǎn)實(shí)驗(yàn)室，唐山 063009；
3. 北京科技大學(xué) 金屬礦山高效開采與安全教育部重點(diǎn)實(shí)驗(yàn)室，北京 100083；
4. 中冶華冶(北京) 國(guó)際貿(mào)易有限公司，北京 100029)
摘 要: 采用同時(shí)平衡原理對(duì)Au-I--H2O系的浸金熱力學(xué)進(jìn)行分析，分別研究溶液與固體Au以及AuI沉淀與固體Au平衡時(shí)的φ-pH關(guān)系、AuI存在條件和溶液中含金組分的變化規(guī)律。結(jié)果表明：隨著溶液中含金組分的總濃度cT(Au)的降低或含碘組分的總濃度cT(I-)的增加，還原電位φsol/Au迅速降低，Au3+/Au2O3的平衡pH值增大，非常有利于金的碘化浸出；隨著溶液中cT(I-)逐漸增加，出現(xiàn)AuI沉淀且其沉淀量呈先增大后減小的趨勢(shì)；在cT(Au)為1×10-4 mol/L的條件下，當(dāng)溶液中cT(I-)濃度大于0.0021 mol/L時(shí)，可避免AuI沉淀的生成，金主要以AuI2-絡(luò)合離子形式存在。Au-I--H2O系的浸金熱力學(xué)分析為金的高效碘化浸出提供了理論依據(jù)。
關(guān)鍵字: Au-I--H2O系；同時(shí)平衡原理；φ-pH圖；AuI沉淀；熱力學(xué)分析
（1. College of Mining Engineering, North China University of Science and Technology, Tangshan 063009, China;
2. Hebei Province Mining Industry Develops with Safe Technology Priority Laboratory, Tangshan 063009, China;
3. Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines,
University of Science and Technology Beijing, Beijing 100083, China;
4. MCC Huaye (Beijing) International Trade Co., Ltd., Beijing 100029, China）
Abstract:Thermodynamic analysis of Au-I--H2O system was carried out based on the principle of simultaneous equilibrium. The φ-pH programs of balance with solution and Au, solid AuI and Au were investigated. Also, the existence condition of AuI precipitation and change-rule of gold-bearing components were studied. The results show that with decreasing cT(Au) or increasing cT(I-) in the solution, φsol/Au reduces rapidly compared to the standard potential of Au, and the balance pH value of Au3+/Au2O3 increases. This is beneficial to gold leaching with iodine-iodide. As the cT(I-) increases gradually in the solution, AuI precipitation appears and the trend of AuI precipitation amount increases firstly and then reduces. When the cT(Au) is 1×10-4 mol/L, if the cT(I-) is more than 0.0021 mol/L, AuI precipitation will not occur, meanwhile, the main complex ion is AuI2-. The thermodynamic analysis of Au-I--H2O system provides theoretical basis for the efficient gold leaching with iodine-iodide.
Key words: Au-I--H2O system; simultaneous equilibrium principle; φ-pH diagram; AuI precipitation; thermodynamic analysis
