Use of jarosite/alunite precipitate as a substitute for gypsum in Portland cement

Katsioti, M; Boura, P; Agatzini, S; Tsakiridis, PE; Oustadakis, P

dc.contributor.author	Katsioti, M	en
dc.contributor.author	Boura, P	en
dc.contributor.author	Agatzini, S	en
dc.contributor.author	Tsakiridis, PE	en
dc.contributor.author	Oustadakis, P	en
dc.date.accessioned	2014-03-01T01:23:18Z
dc.date.available	2014-03-01T01:23:18Z
dc.date.issued	2005	en
dc.identifier.issn	0958-9465	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16894
dc.subject	By-product	en
dc.subject	Cement	en
dc.subject	Gypsum	en
dc.subject	Hydration	en
dc.subject	Jarosite/alunite	en
dc.subject.classification	Construction & Building Technology	en
dc.subject.classification	Materials Science, Composites	en
dc.subject.other	Byproducts	en
dc.subject.other	Crystalline materials	en
dc.subject.other	Gypsum	en
dc.subject.other	Hydration	en
dc.subject.other	Hydrolysis	en
dc.subject.other	Industrial wastes	en
dc.subject.other	Ores	en
dc.subject.other	pH effects	en
dc.subject.other	Positive ions	en
dc.subject.other	Precipitation (chemical)	en
dc.subject.other	Purification	en
dc.subject.other	Supersaturation	en
dc.subject.other	Thermal effects	en
dc.subject.other	X ray diffraction analysis	en
dc.subject.other	Compressive strengths	en
dc.subject.other	Grindability test	en
dc.subject.other	Hydrometallurgical methods	en
dc.subject.other	Jarosite/alunite	en
dc.subject.other	Cement manufacture	en
dc.title	Use of jarosite/alunite precipitate as a substitute for gypsum in Portland cement	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.cemconcomp.2003.10.002	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.cemconcomp.2003.10.002	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	The possibility of replacing the natural gypsum, used in cement production, by a jarosite/alunite chemical precipitate was investigated. This precipitate is a by-product of a new hydrometallurgical process, which was developed in order to treat economically low-grade nickel oxide ores. For this purpose, nine mixtures were produced by substituting gypsum, from 0% to 100%, by the jarosite/alunite precipitate. All samples were tested by determining the setting time, compressive strength, grindability and content of water soluble chromium. Furthermore, XRD analysis was used to determine the hydration products after 2, 7, 28 and 90 days. The jarosite/alunite precipitate was produced from a real laterite heap leach liquor by precipitation at atmospheric pressure, during a series of six runs. More specifically, iron and aluminum were precipitated at 95 degreesC. That was accomplished by gradually raising the initial pH of the leach liquor to an equilibrium pH value of 3.5, at such a rate as to keep supersaturation of iron and aluminum below a critical value. (C) 2004 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Cement and Concrete Composites	en
dc.identifier.doi	10.1016/j.cemconcomp.2003.10.002	en
dc.identifier.isi	ISI:000225152000001	en
dc.identifier.volume	27	en
dc.identifier.issue	1	en
dc.identifier.spage	3	en
dc.identifier.epage	9	en