(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 為實(shí)現(xiàn)濕法煉鋅窯渣磁選鐵精礦(以下簡(jiǎn)稱窯渣鐵精礦)中銀、銅、鐵等有價(jià)元素的綜合回收，提出一種基于鹽酸浸出的新工藝，從理論和實(shí)驗(yàn)兩方面開展研究。在本研究中介紹新工藝研究的理論部分——浸出熱力學(xué)分析。物相分析表明：窯渣鐵精礦中主要含鐵物相為Fe、FeO、FeS、Fe2O3、Fe3O4和FeSiO3。計(jì)算繪制了Fe-Cl--H2O系φ—pH優(yōu)勢(shì)區(qū)圖以及FeS、FeO、FeSiO3-H2O系和FeS、FeO、FeSiO3-Cl--H2O系的lg c —pH圖，分析窯渣鐵精礦鹽酸浸出的熱力學(xué)可行性。結(jié)果表明：各含鐵物相在鹽酸浸出中均能溶解，[Cl-]T越高，其溶解度就越大，由于不同陰離子在體系中溶解性質(zhì)的差異，因此，Cl-影響FeO、FeS和FeSiO3溶解的pH范圍不同，分別為4.2~10.8、0.4~10.8和0~10.8。
關(guān)鍵字: 窯渣鐵精礦；浸出；熱力學(xué)；電勢(shì)(φ)—pH優(yōu)勢(shì)區(qū)圖；濃度對(duì)數(shù)—pH圖
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:For the propose of recovering valuable metals, such as Ag, Cu and Fe comprehensively, in the iron concentrate separated magnetically from kiln slag in zinc hydrometallurgy (hereinafter referred to as kiln slag iron concentrate), a new process of comprehensively utilizing kiln slag iron concentrate was proposed and investigated thermodynamically and experimentally. The first part of the research, i.e., thermodynamic analysis of leaching, was introduced. The phase analysis shows that the main iron containing phases in kiln slag iron concentrate are Fe, FeO, FeS, Fe2O3, Fe3O4 and FeSiO3. The φ—pH predominance diagram of Fe-Cl--H2O system, as well as the lg c —pH diagrams of FeS, FeO, FeSiO3-H2O system and FeS, FeO, FeSiO3-Cl--H2O system were calculated and plotted, aimed at analyzing the thermodynamic feasibility of hydrochloric acid leaching kiln slag iron concentrate. The analysis results show that all of iron phases in the kiln slag iron concentrate are able to dissolve in hydrochloric acid leaching, and the higher the [Cl-]T, the greater the solubility. Due to different natures of anions in the system, the effects of Cl- on the solubility of FeO, FeS and FeSiO3 are not the same, the pH value ranges valid in Cl- effect are 4.2-10.8 for FeO, 0.4-10.8 for FeS and 0-10.8 for FeSiO3.
Key words: kiln slag iron concentrate; leaching; thermodynamic analysis; φ—pH predominance diagram; lg c—pH diagram
