Liquid Copper and Iron Production from Chalcopyrite, in the Absence of Oxygen

Clean energy infrastructure depends on chalcopyrite: the mineral that contains 70% of the world’s copper reserves, as well as a range of precious and critical metals. Smelting is the only commercially viable route to process chalcopyrite, where the oxygen-rich environment dictates the distribution o...

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Bibliographic Details
Main Authors: Katrin E. Daehn, Caspar Stinn, Lucas Rush, Ethan Benderly-Kremen, Mary Elizabeth Wagner, Charles Boury, Brian Chmielowiec, Carolina Gutierrez, Antoine Allanore
Format: Article
Language:English
Published: MDPI AG 2022-08-01
Series:Metals
Subjects:
Online Access:https://www.mdpi.com/2075-4701/12/9/1440
Description
Summary:Clean energy infrastructure depends on chalcopyrite: the mineral that contains 70% of the world’s copper reserves, as well as a range of precious and critical metals. Smelting is the only commercially viable route to process chalcopyrite, where the oxygen-rich environment dictates the distribution of impurities and numerous upstream and downstream unit operations to manage noxious gases and by-products. However, unique opportunities to address urgent challenges faced by the copper industry arise by excluding oxygen and processing chalcopyrite in the native sulfide regime. Through electrochemical experiments and thermodynamic analysis, gaseous sulfur and electrochemical reduction in a molten sulfide electrolyte are shown to be effective levers to selectively extract the elements in chalcopyrite for the first time. We present a new process flow to supply the increasing demand for copper and byproduct metals using electricity and an inert anode, while decoupling metal production from fugitive gas emissions and oxidized by-products.
ISSN:2075-4701