ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Electrochemical aspects of leaching of ocean nodules in the presence and absence of microorganisms

Kumari, A and Natarajan, KA (2002) Electrochemical aspects of leaching of ocean nodules in the presence and absence of microorganisms. In: International Journal of Mineral Processing, 66 (1-4). pp. 29-47.

[img] PDF
Electrochemical_aspects_of_leaching.pdf - Published Version
Restricted to Registered users only

Download (341Kb) | Request a copy
Official URL: http://dx.doi.org/10.1016/S0301-7516(02)00010-8

Abstract

instead of using chemical-reducing agents to facilitate the reduction and dissolution of manganese and iron oxide in the ocean nodule, electrochemical reduction based on two approaches, namely, cathodic polarization and galvanic interaction, can also be considered as attractive alternatives. Galvanic leaching of ocean nodules in the presence of pyrite and pyrolusite for complete recovery of Cu, Ni and Co has been discussed. The key for successful and efficient dissolution of copper, nickel and cobalt from ocean nodules depends on prior reduction of the manganese and ferric oxides with which the above valuable nonferrous metals are interlocked. Polarization studies using a slurry electrode system indicated that maximum dissolution of iron and manganese due to electrochemical reduction occurred at negative DC potentials of -600 mV (SCE) and -1400 mV (SCE). The present work is also relevant to galvanic bioleaching of ocean nodules using autotrophic microorganisms, such as Thiobacillus ferrooxidans and T thiooxidans, which resulted in significant dissolution of copper, nickel and cobalt at the expense of microbiologically generated acids. Various electrochemical and biochemical mechanisms are outlined and the electroleaching and galvanic processes so developed are shown to yield almost complete dissolution of all metal values. (C) 2002 Elsevier Science B.V. All rights reserved.

Item Type: Journal Article
Additional Information: Copyright of this article belongs to Elsevier Science.
Keywords: galvanic leaching;electrobioleaching;ocean nodules
Department/Centre: Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited: 20 Jul 2011 06:40
Last Modified: 20 Jul 2011 06:40
URI: http://eprints.iisc.ernet.in/id/eprint/39165

Actions (login required)

View Item View Item