Lead sulphide leaching kinetics in nitric acid solutions

Halikia, I; Zoumpoulakis, L; Christodoulou, E

dc.contributor.author	Halikia, I	en
dc.contributor.author	Zoumpoulakis, L	en
dc.contributor.author	Christodoulou, E	en
dc.date.accessioned	2014-03-01T01:51:54Z
dc.date.available	2014-03-01T01:51:54Z
dc.date.issued	2002	en
dc.identifier.issn	00442658	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/26502
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0036244301&partnerID=40&md5=348813890057c9cfa93e9541443a621e	en
dc.subject.other	Activation energy	en
dc.subject.other	Diffusion	en
dc.subject.other	Lead compounds	en
dc.subject.other	Nitric acid	en
dc.subject.other	Solutions	en
dc.subject.other	Glass reactors	en
dc.subject.other	Oxidizing agents	en
dc.subject.other	Leaching	en
dc.title	Lead sulphide leaching kinetics in nitric acid solutions	en
heal.type	journalArticle	en
heal.publicationDate	2002	en
heal.abstract	This study presents the results obtained from a kinetic study of lead sulphide leaching in nitric acid solutions at mild conditions. The effects of temperature and oxidizing agent concentration on the kinetic parameters of lead dissolution are investigated. Lead sulphide in powdered form was used for the leaching experiments, which were conducted in a glass reactor placed in a thermomantle. The conditions examined were 27, 40, 50 and 60 °C for temperature and nitric acid solutions with normalities 2, 3, 4 and 5N. The diffusion model equation, i.e. 1 - 2α/3 - (1 - α)2/3 = kt, was found to represent well the experimental data in the whole range of the varying parameters. The reaction progress was favoured by increasing temperature and lixiviant concentration. The activation energy value was determined by Arrhenius plots to 27.7 kJ/mol, when using initial mean rates, and to 62.3 kJ/mol by means of k values of the diffusion model equation at various temperatures, both of which confirming the diffusion mechanism predominance. The order of reaction was evaluated with the r = kCn equation using initial rates to 1.25. When k values from the above model for various leaching solution concentrations were used, the order was determined to 3, indicating stronger influence of the oxidizing agent on the kinetics of lead dissolution at prolonged leaching times.	en
heal.journalName	Erzmetall: Journal for Exploration, Mining and Metallurgy	en
dc.identifier.volume	55	en
dc.identifier.issue	3	en
dc.identifier.spage	166	en
dc.identifier.epage	175	en