Chemical metathesis of chalcopyrite in acidic solutions

Sequeira, CAC; Santos, DMF; Chen, Y; Anastassakis, G

dc.contributor.author	Sequeira, CAC	en
dc.contributor.author	Santos, DMF	en
dc.contributor.author	Chen, Y	en
dc.contributor.author	Anastassakis, G	en
dc.date.accessioned	2014-03-01T01:28:02Z
dc.date.available	2014-03-01T01:28:02Z
dc.date.issued	2008	en
dc.identifier.issn	0304-386X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18676
dc.subject	Chalcopyrite	en
dc.subject	Chemical metathesis	en
dc.subject	Covellite	en
dc.subject	Digenite	en
dc.subject.classification	Metallurgy & Metallurgical Engineering	en
dc.subject.other	Annealing	en
dc.subject.other	Ball milling	en
dc.subject.other	Decomposition	en
dc.subject.other	Leaching	en
dc.subject.other	Reaction rates	en
dc.subject.other	Solutions	en
dc.subject.other	Chalcopyrite	en
dc.subject.other	Chemical metathesis	en
dc.subject.other	Covellite	en
dc.subject.other	Digenite	en
dc.subject.other	Copper compounds	en
dc.title	Chemical metathesis of chalcopyrite in acidic solutions	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.hydromet.2008.02.012	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.hydromet.2008.02.012	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The chemical metathesis of chalcopyrite in the presence of cupric ions was studied in sulphuric acid solutions. The effects of stirring, Cu(II) concentration, temperature and annealing were investigated by leaching and kinetic experiments. The primary reaction involved in the chemical metathesis leads to the formation of covellite, which is followed by an oxidation-reduction couple, with digenite production. This second step was found to be very slow requiring sub-sieve size particles for extensive reaction. The reaction was insensitive to the copper ion concentrations, and practically insensitive to stirring speed. The strain induced by stirred ball milling enhanced the reaction rate markedly due to the recrystallisation process which provides easy paths for diffusion along dislocation and grain boundaries. The kinetics were well correlated with a two-stage product layer diffusion model, with apparent activation energies less than 30 kJ mol(-1), and ferrous ion was found to be the rate determining diffusion species through the covellite phase (first stage) and covellite and digenite phase (second stage). (C) 2008 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Hydrometallurgy	en
dc.identifier.doi	10.1016/j.hydromet.2008.02.012	en
dc.identifier.isi	ISI:000256578900008	en
dc.identifier.volume	92	en
dc.identifier.issue	3-4	en
dc.identifier.spage	135	en
dc.identifier.epage	140	en