Chitosan modification persimmon tannin bioadsorbent for highly efficient removal of Pb(II) from aqueous environment: the adsorption equilibrium, kinetics and thermodynamics.
Environ Technol
; 40(1): 112-124, 2019 Jan.
Article
em En
| MEDLINE
| ID: mdl-28911271
ABSTRACT
Lead (Pb) pollution has triggered a great threat to ecological system as well as public health due to its highly toxic and mutagenic properties. In this study, chitosan surface modified persimmon tannin (PT-CS) biomass composite as an environmental-friendly bioadsorbent for highly efficient removal of Pb(II) from aqueous solutions was investigated. Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy and Zeta potential were used to elucidate the adsorption mechanism. Combining oxidation reaction, electrostatic interaction and chelation reaction, PT-CS exhibited fine adsorption to Pb(II). The maximum adsorption capacity was 179.3â
mg/g. Equilibrium isotherm for the adsorption of Pb(II) was analyzed by the Langmuir, Freundlich and Temkin models, and the Langmuir isotherm (R2 > 0.99) was the best. The pseudo-first-order, pseudo-second-order and intraparticle diffusion equations were used to analyze the kinetic data of the adsorption process and the pseudo-second-order kinetic (Rs2 > 0.98) model was fitted well. Moreover, thermodynamic parameters including ΔG0 < 0, ΔH0 (150.57â
KJ/mol) > 0 and ΔS0 (456.13â
J/molâ
K) > 0 showed that the process of Pb(II) adsorption by PT-CS was spontaneous and endothermic. All these results illustrated that PT-CS would be a promising and low-cost alternative bioadsorbent of Pb(II) in wastewater treatment.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
/
Diospyros
/
Quitosana
Idioma:
En
Revista:
Environ Technol
Ano de publicação:
2019
Tipo de documento:
Article