Logo image
Back
Purification of molybdenum trioxide calcine by selective leaching of copper with HCl–NH4Cl
Journal article   Open access   Peer reviewed

Purification of molybdenum trioxide calcine by selective leaching of copper with HCl–NH4Cl

Y.I. Nam, S.Y. Seo, Y-C Kang, M.J. Kim, G. Senanayake and T. Tran
Hydrometallurgy, Vol.109(1-2), pp.9-17
2011
DOI: https://doi.org/10.1016/j.hydromet.2011.05.001
pdf
Senanayake4.pdfDownloadView
Author’s Version Open Access
url
Link to Published Version *Subscription may be requiredView

Abstract

The leaching of Mo, Cu and Fe from MoO(3) calcines (59-61% Mo) containing 1-2% Cu, 1-2% Fe and other impurities produced from roasting molybdenite (MoS(2)) concentrate was examined using water and a series of chloride lixiviants, including NH(4)Cl (0.6 M), HCl (0.115-1.40 M) and a mixture of HCl (0.70 M) + NH(4)Cl (0.1-0.93 M) at a solid/leachant (w/v) ratio of 1:1 and within the temperature range 25-70 degrees C. Stabcal modelling showed that there are many compounds formed from Cu, Fe and Mo co-exist in the solution. Optimisation studies show that HCl solutions of concentrations >= 0.35 M are capable of dissolving >80% of Cu within 1 h. The addition of NH(4)Cl (0.30-0.93 M) to 0.7 MHCl reduces the dissolution of Mo to <0.5%, due to the formation of a precipitate containing mainly NH(3)(MoO(3))(3), as confirmed by X-ray diffraction. A mixture of 0.7 M HCl and 0.6 M NH(4)Cl at ambient temperatures removes Cu to <0.5% within 2 h, as required for the production of Fe-Mo alloys at Kwangyang Ferro Alloys Co. (Korea). Although not required, Fe was removed to <0.6% whereas most other metal impurities were removed to <0.1%. Pilot plant trials over 7 campaigns, each treating 2.0-2.2 tonnes of MoO(3) calcine containing 2.1% Cu using 1.44 M NH(4)Cl and 0.97 M HCl at an ambient temperature yielded final products containing 0.22% Cu as required. Mass balance calculations (closure to 96-99%) of the pilot plant trials confirm that the Mo loss during leaching is around 0.5%.

Details

Metrics

466 File views/ downloads
138 Record Views
17 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types
Domestic collaboration
International collaboration
Citation topics
7 Engineering & Materials Science
7.229 Mineral & Metal Processing
7.229.774 Bioleaching
Web Of Science research areas
Metallurgy & Metallurgical Engineering
ESI research areas
Materials Science
Logo image