Removal of magnesium from nickel laterite leach liquors by chemical precipitation using calcium hydroxide and the potential use of the precipitate as a filler material

Karidakis, T; Agatzini-Leonardou, S; Neou-Syngouna, P

dc.contributor.author	Karidakis, T	en
dc.contributor.author	Agatzini-Leonardou, S	en
dc.contributor.author	Neou-Syngouna, P	en
dc.date.accessioned	2014-03-01T01:23:01Z
dc.date.available	2014-03-01T01:23:01Z
dc.date.issued	2005	en
dc.identifier.issn	0304-386X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16773
dc.subject	Calcium hydroxide	en
dc.subject	Gypsum	en
dc.subject	Leach liquor	en
dc.subject	Magnesium hydroxide	en
dc.subject	Nickel laterite	en
dc.subject	Polymer filler	en
dc.subject	Precipitation	en
dc.subject.classification	Metallurgy & Metallurgical Engineering	en
dc.subject.other	Leach liquor	en
dc.subject.other	Magnesium hydroxide	en
dc.subject.other	Nickel laterite	en
dc.subject.other	Polymer fillers	en
dc.subject.other	Gypsum	en
dc.subject.other	Hydrated lime	en
dc.subject.other	Nickel compounds	en
dc.subject.other	Precipitation (chemical)	en
dc.subject.other	Scanning electron microscopy	en
dc.subject.other	Stoichiometry	en
dc.subject.other	Magnesium printing plates	en
dc.title	Removal of magnesium from nickel laterite leach liquors by chemical precipitation using calcium hydroxide and the potential use of the precipitate as a filler material	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.hydromet.2004.09.007	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.hydromet.2004.09.007	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	The chemical precipitation of magnesium from sulphate solution, resulting from heap leaching of nickeliferous laterites with sulphuric acid, was studied. Magnesium was removed as hydroxide using calcium hydroxide (Ca(OH)(2)) and the precipitate produced was a mixture of magnesium hydroxide (Mg(OH)(2)) and gypsum (CaSO4 (.) 2H(2)O). The variables studied were the temperature and the stoichiometric quantity of Ca(OH)(2). The responses measured were magnesium removal and the specific surface of the precipitate. Design of the experiments and statistical analysis of the data were used in order to determine the main effects and interactions of the factors. Scanning electron microscopy (SEM) was also used to investigate the effect of precipitation conditions on the morphological characteristics of the Mg(OH)(2)-CaSO4 (.) 2H(2)O mixture. Kinetic analysis with the aid of Nielsen theory allowed the determination of the Mg(OH)(2) formation mechanism. The use of a magnesium hydroxide-gypsum mixture as a filler material was also examined. The suitability of the precipitate was evaluated by measuring a set of properties that can characterize a material as a filler and by measuring mechanical properties of polymers filled with the precipitate at various addition levels. The magnesium hydroxide-gypsum precipitate proved to be promising for this application, as it was found to have similar properties with other commercial products. (C) 2004 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Hydrometallurgy	en
dc.identifier.doi	10.1016/j.hydromet.2004.09.007	en
dc.identifier.isi	ISI:000226874600011	en
dc.identifier.volume	76	en
dc.identifier.issue	1-2	en
dc.identifier.spage	105	en
dc.identifier.epage	114	en