ISSN: 1003-6326
CN: 43-1239/TG
CODEN: TNMCEW

Vol. 27    No. 3    March 2017

Gold self-leaching optimization of neutral roasted products of gold concentrate by response surface methodology
XU Tao1, ZHAO Liu-cheng2, LI Shao-ying2
(1. Department of Business Administration, Chinalco China Copper Corporation Limited, Beijing 100082, China;
2. College of Mining Engineering, North China University of Science and Technology, Tangshan 063009, China
)
Abstract: The method of single experiment and response surface experiment were chosen to optimize the self-leaching process for roasted products of gold concentrate under neutral atmosphere. Different additives, such as Na2SO3, CuSO4, NH3·H2O, Na2CO3 and their concentrations were also optimized. Effects of different additives and their interaction on gold leaching rate, significance and influence order, were analyzed. The results show that gold leaching rate gradually increases as the concentration of Na2SO3 increases. However, gold leaching rate first increases and then decreases with the concentrations of CuSO4, NH3·H2O and Na2CO3. The concentrations of CuSO4 and Na2CO3 have significant effects on the gold leaching rate, and the impact of the concentration of CuSO4 upon the leaching rate is greater than that of Na2CO3. The gold leaching rate reaches 96.31% under the optimum processing conditions that the concentration of Na2SO3 is 0.14 mol/L, NH3·H2O of 2.1 mol/L, CuSO4 of 0.06 mol/L, Na2CO3 of 0.12 mol/L. The error value between the experimental and the predicted value is only 0.86%, indicating that the quadratic polynomial model deduced from the response surface methodology is reasonable. Meanwhile, the process of neutral roasting and gold self-leaching of gold concentrate provides a new way for the high-efficient non-cyanide leaching.
Key words: gold concentrate; neutral roasted product; gold self-leaching; non-cyanide leaching; response surface methodology
Superintended by The China Association for Science and Technology (CAST)
Sponsored by The Nonferrous Metals Society of China (NFSOC)
Managed by Central South University (CSU)