Batch removal of chromium(VI) from aqueous solution by Turkish brown coals
Küçük Resim Yok
Tarih
2007
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
ELSEVIER SCI LTD
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The ability of using low-rank Turkish brown coals (Ilgin: BC1, Bey ehir: BC2, and Ermenek: BC3) to remove Cr(VI) from aqueous solutions was studied as a function of contact time, solution pH, temperature, concentration of metal solutions and amount of adsorbent. Their sorption properties were compared with the activated carbon from Chemviron (AQ-30). Adsorption of Cr(VI) uptake is in all cases pH-dependent showing a maximum at equilibrium pH values between 2.0 and 3.2, depending on the biomaterial, that correspond to initial pH values of 2.3 units for BC1, 3.0 units for BC2 and 3.2 units for BC3 and AQ-30. Batch equilibrium tests showed that the Cr(VI) removal was fitted with Freundlich isotherm and the adsorption reached equilibrium in 80 min. It was proceeding effectively into a short acid pH interval (2.0-3.2) where processes of Cr(VI) sorption are maximized. It was observed that the maximum adsorption capacity of 11.2 mM of Cr(VI)/g for Ilgin (BC1), 12.4 mM of Cr(VI)/g for Beysehir (BC2), 7.4 mM of Cr(VI)/g for Ermenek (BC3) and 6.8 mM of Cr(VI)/g for activated carbon (AQ-30) was achieved at pH of 3.0. The rise in temperature caused a slight decrease in the value of the equilibrium constant (K-c) for the sorption of Cr(VI) ion. The Cr(VI) sorption capacities of Bey ehir and Ilgin brown coals were the same. Ermenek brown coals and activated carbon (AQ-30) showed a similar sorption capacity. (C) 2006 Elsevier Ltd. All rights reserved.
Açıklama
Anahtar Kelimeler
biosorbent, brown coals, hexavalent chromium, removal
Kaynak
BIORESOURCE TECHNOLOGY
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
98
Sayı
15
