Iron-loaded Sphagnum moss extract residue for phosphate removal.
J Environ Manage
; 218: 271-279, 2018 Jul 15.
Article
em En
| MEDLINE
| ID: mdl-29684779
ABSTRACT
Sphagnum moss extract residue (SMER), obtained after pressurized hot water extraction, was modified with Fe(III) and investigated for phosphate sorption. Although moss extract contains value-added compounds, SMER is considered to be waste until suitable uses can be developed. The effect of modification conditions were investigated, i.e. different initial Fe(III) concentrations (0.024, 0.048 and 0.072â¯mol/L Fe3+) and modification pH values (5, 7 and 9). A modification pH of 5 and the highest initial Fe(III) concentration (0.072â¯mol/L Fe3+) resulted in the highest phosphate removal efficiency, and thus was selected for further study. The removal efficiency was found to decrease with increasing pH in the range of 3-9. Maximum removal efficiency (82%) for phosphate sorption was observed at pH 3 after 24â¯h contact time (dosage 2â¯g/L, initial concentration 15â¯mgâ¯P/L). With increased contact time, the phosphate removal efficiency improved and reached equilibrium within 48â¯h. The Elovich model was found to provide the best fit to the kinetic data. A capacity of 9-13â¯mgâ¯P/g was obtained with a 24-h contact time at pH 4. A good fit was achieved with the Redlich-Peterson equation. FTIR analysis confirmed that carboxylic acid groups were involved in the modification process. X-ray diffraction analyses showed that amorphous two-line ferrihydrite was precipitated onto SMER, which was supported by X-ray photoelectron spectroscopy analyses.
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Base de dados:
MEDLINE
Assunto principal:
Fosfatos
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Purificação da Água
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Sphagnopsida
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article