Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Fluoride removal by low-cost palm shell activated carbon modified with prawn shell chitosan adsorbents
AU - Issabayeva, G.
AU - Wong, S.H.
AU - Pang, C.Y.
AU - Wong, M.C.
AU - Aroua, M.K.
PY - 2022/5/31
Y1 - 2022/5/31
N2 - Hydrofluoric acid is used in large volumes during solar panels manufacturing for cleaning purpose. It results in the generation of wastewater containing high concentrations of fluoride. Chemical precipitation is commonly used to remove most of fluoride from the wastewater. It reduces fluoride concentration to ~ 20 mg/L, whereas the discharge standard is set to 2 mg/L. Adsorption is preferable when dealing with diluted wastewater. This study evaluated the adsorption of fluoride using two low-cost adsorbents: granular palm shell activated carbon and its modification with the prepared chitosan of prawn shells. The effects of pH, dosage, contact time and initial fluoride concentration were studied in batch mode adsorption experiments. The highest removal efficiencies of fluoride by two adsorbents comprised 46% and 55%, respectively, at pH 2 and pH 7. The contrasting behavior of the two adsorbents in relation to pH is attributed by the adsorbents surface charge associated with the surface functional groups identified by FTIR. The adsorption isotherm modeling showed better fit to the Langmuir model for both adsorbents. Adsorption kinetics results fitted well into the pseudo-second-order kinetics model suggesting chemisorption mechanism of fluoride removal.
AB - Hydrofluoric acid is used in large volumes during solar panels manufacturing for cleaning purpose. It results in the generation of wastewater containing high concentrations of fluoride. Chemical precipitation is commonly used to remove most of fluoride from the wastewater. It reduces fluoride concentration to ~ 20 mg/L, whereas the discharge standard is set to 2 mg/L. Adsorption is preferable when dealing with diluted wastewater. This study evaluated the adsorption of fluoride using two low-cost adsorbents: granular palm shell activated carbon and its modification with the prepared chitosan of prawn shells. The effects of pH, dosage, contact time and initial fluoride concentration were studied in batch mode adsorption experiments. The highest removal efficiencies of fluoride by two adsorbents comprised 46% and 55%, respectively, at pH 2 and pH 7. The contrasting behavior of the two adsorbents in relation to pH is attributed by the adsorbents surface charge associated with the surface functional groups identified by FTIR. The adsorption isotherm modeling showed better fit to the Langmuir model for both adsorbents. Adsorption kinetics results fitted well into the pseudo-second-order kinetics model suggesting chemisorption mechanism of fluoride removal.
KW - Adsorption
KW - Chitosan
KW - Fluoride
KW - Low cost
KW - Palm shell activated carbon
KW - Prawn shell
KW - Wastewater
KW - Activated carbon
KW - Costs
KW - Precipitation (chemical)
KW - Shellfish
KW - Shells (structures)
KW - Adsorption experiment
KW - Adsorption isotherm model
KW - Chemical precipitation
KW - Fluoride concentrations
KW - Palm shell-activated carbon
KW - Pseudo second order kinetics
KW - Removal efficiencies
KW - Surface functional groups
KW - Fluorine compounds
U2 - 10.1007/s13762-021-03448-2
DO - 10.1007/s13762-021-03448-2
M3 - Journal article
VL - 19
SP - 3731
EP - 3740
JO - International Journal of Environmental Science and Technology
JF - International Journal of Environmental Science and Technology
SN - 1735-1472
IS - 6
ER -