Electrochemical modeling and study of copper deposition from concentrated ammoniacal sulfate solutions

Giannopoulou, I; Panias, D; Paspaliaris, I

dc.contributor.author	Giannopoulou, I	en
dc.contributor.author	Panias, D	en
dc.contributor.author	Paspaliaris, I	en
dc.date.accessioned	2014-03-01T01:30:19Z
dc.date.available	2014-03-01T01:30:19Z
dc.date.issued	2009	en
dc.identifier.issn	0304-386X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19547
dc.subject	Copper ammine	en
dc.subject	Copper deposition	en
dc.subject	Electrochemistry	en
dc.subject	Potentiostatic reduction	en
dc.subject	Thermodynamic modeling	en
dc.subject.classification	Metallurgy & Metallurgical Engineering	en
dc.subject.other	Ammine complexes	en
dc.subject.other	Ammoniacal solution	en
dc.subject.other	Cathodic deposition	en
dc.subject.other	Cathodic reactions	en
dc.subject.other	Cell voltages	en
dc.subject.other	Copper deposition	en
dc.subject.other	Electrochemical behaviors	en
dc.subject.other	Electrochemical experiments	en
dc.subject.other	Electrochemical modeling	en
dc.subject.other	Electrolytic deposition	en
dc.subject.other	High ionic strength	en
dc.subject.other	Induction periods	en
dc.subject.other	Metallic copper	en
dc.subject.other	Oxidative conditions	en
dc.subject.other	Potentiostatic reduction	en
dc.subject.other	Redox condition	en
dc.subject.other	Redox potentials	en
dc.subject.other	Redox systems	en
dc.subject.other	Sigmoid curves	en
dc.subject.other	Sulfate solutions	en
dc.subject.other	Thermo dynamic analysis	en
dc.subject.other	Thermodynamic modeling	en
dc.subject.other	Two-step mechanisms	en
dc.subject.other	Two-step reduction	en
dc.subject.other	Type curves	en
dc.subject.other	Cell membranes	en
dc.subject.other	Copper	en
dc.subject.other	Copper metallurgy	en
dc.subject.other	Copper plating	en
dc.subject.other	Deposition	en
dc.subject.other	Electric potential	en
dc.subject.other	Electrochemistry	en
dc.subject.other	Electrolytic analysis	en
dc.subject.other	Ionic strength	en
dc.subject.other	Redox reactions	en
dc.subject.other	Reduction	en
dc.subject.other	Thermoanalysis	en
dc.subject.other	Thermodynamics	en
dc.subject.other	Copper compounds	en
dc.title	Electrochemical modeling and study of copper deposition from concentrated ammoniacal sulfate solutions	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.hydromet.2009.06.009	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.hydromet.2009.06.009	en
heal.language	English	en
heal.publicationDate	2009	en
heal.abstract	A fundamental investigation of the electrolytic deposition of copper from concentrated aqueous ammoniacal solutions has been carried out based on the thermodynamic analysis of the system Cu-NH3-H2O. The speciation of copper vs. pH and redox potential was modeled in high ionic strength solutions, in which the activity coefficients of the system species were estimated according to the Modified Bromley's Methodology. The electrochemical behavior of the redox system Cu(0)/Cu(I)/Cu(II) in concentrated aqueous ammoniacal solutions was studied at pH = 9.5 and the cathodic reactions in these solutions were determined. It was found that metallic copper was formed under strongly reductive redox conditions. while under mildly reductive to mildly oxidative conditions the cuprous di-ammine complex species dominate. Under highly oxidative conditions the cupric tetra-ammine complex species predominated. According to the theory and results, the cathodic deposition of copper from concentrated aqueous ammoniacal solutions proceeds in a two-step reduction mechanism. The cupric ammine species are first reduced to cuprous di-ammine, which in turn is reduced to metallic copper. The electrochemical experiments revealed that copper deposition over time follows a sigmoid-type curve, verifying the two-step mechanism. The main feature of these sigmoid curves was the presence of an induction period with negligible copper deposition, followed by an acceleration period where the copper deposition rate gradually increased. By increasing the applied cell voltage, the induction period was significantly reduced or disappeared. (C) 2009 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Hydrometallurgy	en
dc.identifier.doi	10.1016/j.hydromet.2009.06.009	en
dc.identifier.isi	ISI:000270120100011	en
dc.identifier.volume	99	en
dc.identifier.issue	1-2	en
dc.identifier.spage	58	en
dc.identifier.epage	66	en