Abstract
The direct cyanide leaching rate of gold from a gold calcine was only 71.33%, due to 19.51% of gold being encapsulated in the iron oxides. To enhance the cyanide leaching of gold, the calcine was pretreated by acid and alkali washing and the relevant intensifying mechanism was also researched. The results showed that the cyanide leaching rate of gold after acid or alkali washing was increased to 82.24 and 87.07%, respectively. It was found that acid washing could remove iron oxides, but the dissolution of iron oxide particles was incomplete that part of gold was still encapsulated. However, alkali washing could effectively remove silicates and obtain rough and porous calcine particles. It was found that the blockage of pores in iron oxides by silicates was the primary reason for the low gold leaching rate of calcine and alkali washing was more favorable for exposing gold than acid washing.
This is a preview of subscription content, log in via an institution.
References
L. Hou et al, Volatilization behavior and mechanisms of arsenic, sulfur and carbon in the refractory gold concentrate, in TMS, 6th International Symposium on High-Temperature Metallurgical Processing (2015), pp. 163–170
J. Hu, Research on the process of roasting pretreatment-cyanide extracting au from sulfide-bearing refractory gold concentrate containing arsenic and high-carbon. Master thesis, Central South University (2015), pp. 10–20
L. Wang et al., Research on encapsulation of roasted refractory gold concentrate. Chin. J. Rare Metal. 29, 424–428 (2005)
W. Kou, G. Chen, Research and practice on improving cyanidation recovery of the refractory gold bearing sulfide concentrate from a two-stage roasting process. Gold 33, 47–49 (2012)
C. Komnitsas, F.D. Pooley, Mineralogical characteristics and treatment of refractory gold ores. Miner. Eng. 2, 449–457 (1989)
K.G. Thomas, A.P. Cole, Roasting developments-especially oxygenated roasting. Dev. Miner. Process. 15, 403–432 (2005)
Xu Bin et al., Fluidized roasting-stage leaching of a silver and gold bearing polymetallic sulfide concentrate. Hydrometallurgy 147–148, 79–82 (2014)
Yongbin Yang et al., Pretreatment by sulfuric acid-curing of calcine roasting for gold ores with high sulfur and arsenic contents. Chin. J. Nonferrous Met. 24, 2380–2386 (2014)
Hu Yaoqin et al., Mineralogical study of roasting of gold concentrate and analysis of difficulty in leaching gold of residue. Nonferrous Met. 51, 52–56 (1999)
Y. Li et al, Roasting technology of refractory and complex gold ore using circulating fluid bed. Nonferrous Met. (Extr. Metall.) (2011), 31–33
H. Li, W. Wang, X. Zhang, Method of gold leaching by pretreating gold bearing tailing or cyanidation residue to remove silicon. China patent. No. CN201410412434.2 (2014)
J. Wang, B. Li, The stability and solubility of CaSO4·2H2O and Ca(OH)2 in high concentrate KOH–NaOH–H2O system. Chem. Eng. S2, 413 (2009)
Acknowledgements
This work was financially supported by National Natural Science Foundation of China (Grant No. 51574284), National Science Foundation for Distinguished Young Scholars of China (Grant No. 51504293), Science and Technology Program of Yunnan (No. 2013IB020).
Author information
Authors and Affiliations
Corresponding authors
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2017 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Zhang, Y. et al. (2017). Mechanism of Intensifying Cyanide Leaching of Gold from a Calcine by the Pretreatment of Acid or Alkali Washing. In: Kim, H., Alam, S., Neelameggham, N., Oosterhof, H., Ouchi, T., Guan, X. (eds) Rare Metal Technology 2017. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-51085-9_15
Download citation
DOI: https://doi.org/10.1007/978-3-319-51085-9_15
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-51084-2
Online ISBN: 978-3-319-51085-9
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)