Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Selectivity in cation exchange property of heat-treated brown coals
Autore:
Murakami, K; Yamada, T; Fuda, K; Matsunaga, T;
Indirizzi:
Akita Univ, Fac Engn & Resource Sci, Dept Mat Proc Engn & Appl Chem Environm, Akita 0108502, Japan Akita Univ Akita Japan 0108502 Appl Chem Environm, Akita 0108502, Japan
Titolo Testata:
FUEL
fascicolo: 4, volume: 80, anno: 2001,
pagine: 599 - 605
SICI:
0016-2361(200103)80:4<599:SICEPO>2.0.ZU;2-Z
Fonte:
ISI
Lingua:
ENG
Soggetto:
ADSORPTION;
Keywords:
Australian brown coal; selective cation exchange; structural changes of brown coal;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Engineering, Computing & Technology
Citazioni:
16
Recensione:
Indirizzi per estratti:
Indirizzo: Murakami, K Akita Univ, Fac Engn & Resource Sci, Dept Mat Proc Engn & ApplChem Environm, Akita 0108502, Japan Akita Univ Akita Japan 0108502 nvironm, Akita 0108502, Japan
Citazione:
K. Murakami et al., "Selectivity in cation exchange property of heat-treated brown coals", FUEL, 80(4), 2001, pp. 599-605

Abstract

The selectivity in cation exchange of Loy Yang brown coal treated at 50-250 degreesC was studied in an aqueous solution containing two kinds of metallic ions to clarify the effects of the heat treatment temperatures of coal,pH of the exchange solution, and addition of acetone to the exchange solution. Four divalent metallic ions of Co2+, Mg2+, Ni2+, Ca2+, mainly the former two, were used as exchange cations. The amount of Co2+ adsorption (the extent of cation exchange for Co2+, Co-ECE) from the Co-Mg mixed solution atpH 6 for the coal treated at 50 degreesC was 1.15 mmol g-coal(-1), almost the same value as that from the single Co2+ ionic solution, whereas the Mg-ECE from the Co-Mg mixed solution decreased to 1/6 of that from the single Mg2+ ionic solution which was 0.8 mmol g(-1), indicating that the ability of cation exchange of Co2+ is much higher than that of Mg2+, the selectivityof Co2+ (the ratio of the Co-ECE to the sum of the Co-ECE and the Mg-ECE) about 90%. With decreasing pH of the solution, however, the selectivity of Co2+ decreased. The selectivity of Co2+, the low pH region between 2 and 5.5 decreased further for the heat-treated coal samples at higher temperatures. On the other hand, in the higher pH region, the selectivity of Co2+ was recovered to larger than 70% independent of heat treatment temperatures. Byaddition of acetone to the exchange solution, the selectivity of Co2+ was also recovered up to about 50% even in the low pH region. These changes of the selectivity in cation exchange are discussed based on the structural changes of brown coal. (C) 2001 Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 27/11/20 alle ore 00:53:02