Leaching of lead from clinoptilolite at acidic conditions

Petrakakis, Y; Mylona, E; Georgantas, D; Grigoropoulou, H

dc.contributor.author	Petrakakis, Y	en
dc.contributor.author	Mylona, E	en
dc.contributor.author	Georgantas, D	en
dc.contributor.author	Grigoropoulou, H	en
dc.date.accessioned	2014-03-01T01:56:30Z
dc.date.available	2014-03-01T01:56:30Z
dc.date.issued	2007	en
dc.identifier.issn	1790-7632	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/28128
dc.subject	clinoptilolite	en
dc.subject	lead	en
dc.subject	leaching	en
dc.subject	acid treatment	en
dc.subject.classification	Environmental Sciences	en
dc.subject.other	NATURAL CLINOPTILOLITE	en
dc.subject.other	ION-EXCHANGE	en
dc.subject.other	HEAVY-METALS	en
dc.subject.other	CR3+	en
dc.subject.other	CU2+	en
dc.subject.other	PB2+	en
dc.subject.other	FE3+	en
dc.title	Leaching of lead from clinoptilolite at acidic conditions	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2007	en
heal.abstract	The leachability of Pb2+ from natural greek clinoptilolite was investigated according to the standard procedures TCLP/EPA/RCRA (1311), EPA Methods 1310, 1320 and DIN 38414-S4. Through SEM/EDAX analysis it was shown that lead was uniformly loaded onto the particles subjected to acid treatment. Sorption was fast during the first few hours and equilibrium was practically attained after 24 h. pH was the dominant factor affecting leaching and for values 3 and higher less than 1% of the metal was leached out while at pH=1 up to 20% of the lead initially present on the solid was leached out. At 1.5 and 2, lead was re-adsorbed after initial leaching. % leaching after 24h was found to increase with increasing initial load (17 to 44% for 15 to 100 mgPb(2+)/g(clin)). Agitation rate (50-180 rpm) and particle size (1.4-2 mm and 5-6 mm) did not affect leaching. Higher temperature (25-40 degrees C) resulted in increased leaching rates. Despite the limited number of data, leaching seems to follow third-order kinetics. Finally, exposure to acid conditions increased markedly the specific surface (from 35.1 to 79.4 m(2) g(-1)), and lowered the average pore diameter (from 80.8 to 42.9 angstrom) of the clinoptilolite particles.	en
heal.publisher	GLOBAL NETWORK ENVIRONMENTAL SCIENCE & TECHNOLOGY	en
heal.journalName	GLOBAL NEST JOURNAL	en
dc.identifier.isi	ISI:000254825600004	en
dc.identifier.volume	9	en
dc.identifier.issue	3	en
dc.identifier.spage	207	en
dc.identifier.epage	213	en