Activated carbon from cotton stalks by impregnation with phosphoric acid

Citation
Bs. Girgis et Mf. Ishak, Activated carbon from cotton stalks by impregnation with phosphoric acid, MATER LETT, 39(2), 1999, pp. 107-114
Citations number
34
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
MATERIALS LETTERS
ISSN journal
0167577X → ACNP
Volume
39
Issue
2
Year of publication
1999
Pages
107 - 114
Database
ISI
SICI code
0167-577X(199904)39:2<107:ACFCSB>2.0.ZU;2-U
Abstract
Dried, crushed cotton stalks were impregnated with varying concentrations o f phosphoric acid (20-85 wt.%), dried at 383 K and carbonized at 773 K for 2 h. Porosity was determined by analysis of N-2/77 K adsorption isotherms. High adsorbing carbons with well developed mesoporosity were obtained. Anal ysis for microporosity, by the alpha(S)-method, proved the presence of mino r content in all products. Non-dried impregnated precursor produced a carbo n with much lower adsorption capacity, whereas carbonization at 673 K furni shed a carbon with comparatively lower texture parameters. TG analysis of t he acid-impregnated precursor exhibited considerable modification in the py rolysis characteristics. The effect of activant was associated with its eff ect as dehydrant, shift in decomposition to higher temperatures, suppressio n of volatiles, and space left by its leaching thereafter. (C) 1999 Elsevie r Science B.V. All rights reserved.