TY - JOUR
T1 - Investigations on lignite use for lead removal from aqueous solutions under static and dynamic conditions
T2 - Adsorption properties andmechanism exploration
AU - Mlayah, Ammar
AU - Jellali, Salah
AU - Azzaz, Ahmed Amine
AU - Jeguirim, Mejdi
AU - Sellalmi, Haykel
AU - Hamdi, Noureddine
N1 - Funding Information:
The authors gratefully acknowledge the Tunisian Ministry of Higher Education and Scientific Research for financing this research project.
Publisher Copyright:
© 2021 Elsevier Masson SAS. All rights reserved.
PY - 2021
Y1 - 2021
N2 - Lignite, as an abundant and low-cost material, was tested for lead (Pb(II)) removal from aqueous solutions under various experimental conditions for both static (batch) and dynamic (column) experiments. Static assays showed that Pb(II) removal efficiency increases with rising in its initial concentration, aqueous pH, and adsorbent dosage values. Adsorption kinetic and isothermal data were well fitted with the pseudo-second-order and Freundlich models, respectively, suggesting that lead removal by lignite is mainly governed by chemical processes and occurs heterogeneously on multilayer surfaces. The maximum Langmuir's adsorption capacity was equal to 61.4 mg g 1, which is high in comparison to various natural materials. The laboratory column experiments showed that Pb(II) breakthrough curves and subsequent lignite adsorption efficiency is highly dependent on the bed height. Due to the short time contact between Pb(II) and lignite particles inside the column, the highest adsorption capacity was about 21%, which is lower than the one found in the batch mode. Even under dynamic conditions, lignite exhibits a high adsorption capacity compared to other adsorbents, which promotes its use as a low-cost and efficient material for Pb(II) and the removal of other heavy metals from wastewaters.
AB - Lignite, as an abundant and low-cost material, was tested for lead (Pb(II)) removal from aqueous solutions under various experimental conditions for both static (batch) and dynamic (column) experiments. Static assays showed that Pb(II) removal efficiency increases with rising in its initial concentration, aqueous pH, and adsorbent dosage values. Adsorption kinetic and isothermal data were well fitted with the pseudo-second-order and Freundlich models, respectively, suggesting that lead removal by lignite is mainly governed by chemical processes and occurs heterogeneously on multilayer surfaces. The maximum Langmuir's adsorption capacity was equal to 61.4 mg g 1, which is high in comparison to various natural materials. The laboratory column experiments showed that Pb(II) breakthrough curves and subsequent lignite adsorption efficiency is highly dependent on the bed height. Due to the short time contact between Pb(II) and lignite particles inside the column, the highest adsorption capacity was about 21%, which is lower than the one found in the batch mode. Even under dynamic conditions, lignite exhibits a high adsorption capacity compared to other adsorbents, which promotes its use as a low-cost and efficient material for Pb(II) and the removal of other heavy metals from wastewaters.
KW - Adsorption mechanisms
KW - Batch
KW - Column
KW - Lead removal
KW - Lignite
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U2 - 10.5802/CRCHIM.71
DO - 10.5802/CRCHIM.71
M3 - Article
AN - SCOPUS:85107825969
SN - 1631-0748
VL - 24
JO - Comptes Rendus Chimie
JF - Comptes Rendus Chimie
ER -