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Titolo:
NH4+, Cu2+, Zn2+, Cd2+ and Pb2+ exchange for Na+ in a sedimentary clinoptilolite, North Sardinia, Italy
Autore:
Langella, A; Pansini, M; Cappelletti, P; de Gennaro, B; de Gennaro, M; Colella, C;
Indirizzi:
Univ Naples Federico II, Dipartimento Ingn Mat & Prod, I-80125 Naples, Italy Univ Naples Federico II Naples Italy I-80125 Prod, I-80125 Naples, Italy Univ Sannio, I-82100 Benevento, Italy Univ Sannio Benevento Italy I-82100 niv Sannio, I-82100 Benevento, Italy Univ Cassino, Dipartimento Ingn Ind, I-03043 Cassino, FR, Italy Univ Cassino Cassino FR Italy I-03043 ngn Ind, I-03043 Cassino, FR, Italy Univ Naples Federico II, Dipartimento Sci Terra, I-80134 Naples, Italy Univ Naples Federico II Naples Italy I-80134 erra, I-80134 Naples, Italy
Titolo Testata:
MICROPOROUS AND MESOPOROUS MATERIALS
fascicolo: 3, volume: 37, anno: 2000,
pagine: 337 - 343
SICI:
1387-1811(200006)37:3<337:NCZCAP>2.0.ZU;2-Y
Fonte:
ISI
Lingua:
ENG
Soggetto:
NATURAL ZEOLITES; ION-EXCHANGE; EQUILIBRIA; FERRIERITE; MORDENITE; MINERALS; REMOVAL; SODIUM;
Keywords:
ammonium; cadmium; cation exchange; clinoptilolite; copper; lead; zinc;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
34
Recensione:
Indirizzi per estratti:
Indirizzo: Colella, C Univ Naples Federico II, Dipartimento Ingn Mat & Prod, Piazzale5 Tecchio 80, I-80125 Naples, Italy Univ Naples Federico II Piazzale 5 Tecchio 80 Naples Italy I-80125
Citazione:
A. Langella et al., "NH4+, Cu2+, Zn2+, Cd2+ and Pb2+ exchange for Na+ in a sedimentary clinoptilolite, North Sardinia, Italy", MICROP M M, 37(3), 2000, pp. 337-343

Abstract

Recent findings of clinoptilolite-bearing volcanoclastic deposits in northern Sardinia promoted a study aimed at evaluating the cation exchange properties of this zeolite in view of a possible future utilization of the parent rock. Isotherms of NH4+, Cu2+, Zn2+, Cd2+ and Pb2+ exchange for Na+ at 25degrees C and 0.1 total normality were obtained and the related thermodynamic quantities K-a and Delta G(0) computed. The maximal exchange level was in any case less than 100% for each cation investigated. Good selectivitieswere recorded for NH4+ and Pb2+, whereas clinoptilolite proved to be unselective for Cu2+, Zn2+ and Cd2+ The cation selectivity sequence NH4+ > Pb2+>Na+> Cd2+ >Cu2+ congruent to Zn2+ was obtained. The results are discussed in the light of literature data, and contrastingperformances of various clinoptilolites were ascribed to different cationic compositions of the minerals, due to different minerogenetic conditions, which were proved to affect both cation exchange capacity and selectivity. This led to the conclusion that any practical utilization of a clinoptilolite-rich rock as cation exchanger should be preceded by basic studies on representative samples from the deposit under examination. (C) 2000 Elsevier Science B.V. All rights reserved.

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Documento generato il 22/09/20 alle ore 11:09:20