摘要
The kinetics of pressure leaching high iron sphalerite concentrate was studied.The effects of agitation rate,temperature, oxygen partial pressure,initial acid concentration,particle size,iron content in the concentrate and concentration of Fe2 +added into the solution on the leaching rate of zinc were examined.The experiment results indicate that if the agitation rate is greater than 600 r/min,its influence on Zn leaching rate is not substantial.A suitable rise in temperature can facilitate the leaching reaction,and the temperature should be controlled at 140-150℃.The increase trend of Zn leaching rate becomes slow when pressure is greater than 1.2 MPa,so the pressure is controlled at 1.2-1.4 MPa.Under the conditions of this study,Zn leaching rate decreases with a rise in the initial sulfuric acid concentration;and Zn leaching rate increases with a rise of iron content in the concentrate and Fe 2+ concentration in the solution.Moreover,the experiment demonstrates that the leaching process follows the surface chemical reaction control kinetic law of“shrinking of unreacted core”.The activation energy for pressure leaching high iron sphalerite concentrate is calculated,and a mathematical model for this pressure leaching is obtained.The model is promising to guide the practical operation of pressure leaching high iron sphalerite concentrate.
The kinetics of pressure leaching high iron sphalerite concentrate was studied. The effects of agitation rate, temperature, oxygen partial pressure, initial acid concentration, particle size, iron content in the concentrate and concentration of Fe^2＋ added into the solution on the leaching rate of zinc were examined. The experiment results indicate that if the agitation rate is greater than 600 r/min, its influence on Zn leaching rate is not substantial. A suitable rise in temperature can facilitate the leaching reaction, and the temperature should be controlled at 140-150 ℃. The increase trend of Zn leaching rate becomes slow when pressure is greater than 1.2 MPa, so the pressure is controlled at 1.2-1.4 MPa. Under the conditions of this study, Zn leaching rate decreases with a rise in the initial sulfuric acid concentration; and Zn leaching rate increases with a rise of iron content in the concentrate and Fe^2＋ concentration in the solution. Moreover, the experiment demonstrates that the leaching process follows the surface chemical reaction control kinetic law of＂shrinking of unreacted core＂. The activation energy for pressure leaching high iron sphalerite concentrate is calculated, and a mathematical model for this pressure leaching is obtained. The model is promising to guide the practical operation of pressure leaching high iron sphalerite concentrate.
出处
《中国有色金属学会会刊：英文版》
EI
CSCD
2007年第1期187-194,共8页
Transactions of Nonferrous Metals Society of China
基金
Project(2002GG01)supported by Yunnan Metallurgical General Company,China
关键词
闪锌矿
数学模型
化学反应
能量
精矿
high iron sphalerite concentrate
pressure leaching
kinetics
activation energy
mathematical model
