Comparative studies on adsorptive removal of heavy metal ions by biosorbent, bio-char and activated carbon obtained from low cost agro-residue
Küçük Resim Yok
Tarih
2016
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
IWA PUBLISHING
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In this study, Fe(III) and Cr(III) metal ion adsorption processes were carried out with three adsorbents in batch experiments and their adsorption performance was compared. These adsorbents were sesame stalk without pretreatment, bio-char derived from thermal decomposition of biomass, and activated carbon which was obtained from chemical activation of biomass. Scanning electron microscopy and Fourier transform-infrared techniques were used for characterization of adsorbents. The optimum conditions for the adsorption process were obtained by observing the influences of solution pH, adsorbent dosage, initial solution concentration, contact time and temperature. The optimum adsorption efficiencies were determined at pH 2.8 and pH 4.0 for Fe(III) and Cr(III) metal ion solutions, respectively. The experimental data were modelled by different isotherm models and the equilibriums were well described by the Langmuir adsorption isotherm model. The pseudo-first-order, pseudo-second-order kinetic, intra-particle diffusion and Elovich models were applied to analyze the kinetic data and to evaluate rate constants. The pseudo-second-order kinetic model gave a better fit than the others. The thermodynamic parameters, such as Gibbs free energy change Delta G degrees, standard enthalpy change Delta H degrees and standard entropy change Delta S degrees were evaluated. The thermodynamic study showed the adsorption was a spontaneous endothermic process.
Açıklama
Anahtar Kelimeler
adsorption, biosorption, heavy metal, isotherm, kinetic, thermodynamic
Kaynak
WATER SCIENCE AND TECHNOLOGY
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
73
Sayı
2
