The utilization of Ca-rich and Ca-Si-rich fly ashes in zeolites production

Moutsatsou, A; Stamatakis, E; Hatzitzotzia, K; Protonotarios, V

dc.contributor.author	Moutsatsou, A	en
dc.contributor.author	Stamatakis, E	en
dc.contributor.author	Hatzitzotzia, K	en
dc.contributor.author	Protonotarios, V	en
dc.date.accessioned	2014-03-01T01:25:17Z
dc.date.available	2014-03-01T01:25:17Z
dc.date.issued	2006	en
dc.identifier.issn	0016-2361	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17634
dc.subject	Alkaline activation	en
dc.subject	Lignite fly ash	en
dc.subject	NaP	en
dc.subject	NaP1	en
dc.subject	Synthesized zeolites	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Alkaline earth metals	en
dc.subject.other	Calcium	en
dc.subject.other	Chemistry	en
dc.subject.other	Coal combustion	en
dc.subject.other	Density (specific gravity)	en
dc.subject.other	Heavy metals	en
dc.subject.other	Lignite	en
dc.subject.other	Mineralogy	en
dc.subject.other	pH	en
dc.subject.other	Scanning electron microscopy	en
dc.subject.other	Silicate minerals	en
dc.subject.other	Silicon	en
dc.subject.other	Sodium compounds	en
dc.subject.other	X ray diffraction analysis	en
dc.subject.other	Zeolites	en
dc.subject.other	Alkaline activation	en
dc.subject.other	Lignite fly ash	en
dc.subject.other	NaP	en
dc.subject.other	NaP1	en
dc.subject.other	Synthesized zeolites	en
dc.subject.other	Fly ash	en
dc.title	The utilization of Ca-rich and Ca-Si-rich fly ashes in zeolites production	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.fuel.2005.09.008	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.fuel.2005.09.008	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	Two Greek lignite fly ashes (FAs), with relatively different mineralogy and chemistry, were examined for their ability of giving rise to zeolitic material under alkaline activation. The two FAs were collected from Ptolemais (PFA) and Megalopolis (MFA) Lignite Power Plants and underwent a hydrothermal treatment utilizing sodium hydroxide solution 1 M, at a temperature of 90 degrees C for 24 h. Four different FA/NaOH ratios (25, 50, 100 and 150 g L-1) were examined for each of the FAs. Experimental products were characterized by means of X-ray diffraction analysis and scanning electron microscopy and also evaluated in terms of their cation exchange capacity (CEC), specific surface area (SSA), specific gravity (SG) and pH. Results showed relatively similar behavior for the two FAs and a significant mono-mineral zeolite formation for FA/NaOH = 50 a L-1. For the particular ratio, NaP1 (Gobbinsite, GIS-type), and NaP zeolites were formed from aluminosilicate glass digestion. For lower FA/NaOH ratios, the excess of NaOH seems to be prohibitive for zeolite growth, while for the highest solid/liquid ratios, the NaOH quantity seems to be insufficient for the effective activation of the FAs. The values of CEC and SSA were also higher for FA/NaOH = 50 g L-1, with the MFA presenting the best results. The authors' current work focuses on testing the products of the aforementioned zeolitization process for their potential of retaining heavy metals from a contaminated soil. (C) 2005 Published by Elsevier Ltd.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Fuel	en
dc.identifier.doi	10.1016/j.fuel.2005.09.008	en
dc.identifier.isi	ISI:000234764900009	en
dc.identifier.volume	85	en
dc.identifier.issue	5-6	en
dc.identifier.spage	657	en
dc.identifier.epage	663	en