Hexavalent chromium adsorption on superparamagnetic multi-wall carbon nanotubes and activated carbon composites
Küçük Resim Yok
Tarih
2014
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Inst Chemical Engineers
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Hexavalent chromium (Cr(VI)) adsorption from aqueous solutions on magnetically modified multi-wall carbon nanotubes (M-MWCNT) and activated carbon (M-AC) was investigated. M-MWCNT and M-AC were prepared by co-precipitation method with Fe2+:Fe3+ salts as precursors. The magnetic adsorbents were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscope (SEM). The effects of amount of adsorbents, contact time, initial pH, temperature and the initial concentration of Cr(VI) solution were determined. The adsorption equilibrium, kinetics, thermodynamics and desorption of Cr(VI) were investigated. Equilibrium data fitted well with the Langmuir isotherm forboth of the adsorbents. The theoretical adsorption capacities are 14.28 mg/g of M-MWCNT and 2.84 mg/g of M-AC. Cr(VI) adsorption kinetics was modeled with pseudo-second order model, intraparticle diffusion model and Bangham model. Thermodynamic parameters were calculated and AG, Ali and AS indicate that the adsorption of Cr(VI) onto M-MWCNT and M-AC was exothermic and spontaneous in nature. Results revealed that M-MWCNT is an easily separated effective adsorbent for Cr(VI) adsorption from aqueous solution. (C) 2014 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Açıklama
Anahtar Kelimeler
MWCNT/Fe3O4, Activated carbon/Fe3O4, Cr(VI), Adsorption
Kaynak
Chemical Engineering Research & Design
WoS Q Değeri
Q2
Scopus Q Değeri
Q2
Cilt
92
Sayı
11
