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 - Comparison of properties and aquatic arsenic removal potentials of organically modified smectite adsorbents
AU - Mukhopadhyay, Raj
AU - Manjaiah, K. M.
AU - Datta, S. C.
AU - Sarkar, Binoy
PY - 2019/9/5
Y1 - 2019/9/5
N2 - Arsenic (As)poses a tremendous threat to human health due to exposure through arsenic-contaminated drinking water and/or food. We aimed to develop organically modified clay adsorbents for the removal of As from aqueous solution. We modified a smectite sample using three organic agents, namely hexadecyl trimethylammonium (HDTMA), chitosan and citric acid, and characterized the products using X-ray diffraction, infrared spectroscopy, and scanning electron microscopy techniques. The characterization techniques suggested successful organic modifications of the smectite sample. The surfactant-modified smectite was the most efficient (66.9%)As removing adsorbent with a maximum adsorption capacity of 473.2 μg g−1. Kinetic study showed that the adsorbents reached As adsorption equilibrium within 3 h, and the data fitted reasonably well to power function and simple Elovich equations (R2 > 0.89). The adsorption data were explained well by the Freundlich and Sips isothermal models. The surfactant-modified and chitosan-grafted organoclays adsorbed As by electrostatic attraction and anion exchange, whereas the citric acid activated smectite followed ligand exchange and simple anion exchange mechanisms. This study thus demonstrated the potential of surfactant-modified clays in removing As from contaminated waters.
AB - Arsenic (As)poses a tremendous threat to human health due to exposure through arsenic-contaminated drinking water and/or food. We aimed to develop organically modified clay adsorbents for the removal of As from aqueous solution. We modified a smectite sample using three organic agents, namely hexadecyl trimethylammonium (HDTMA), chitosan and citric acid, and characterized the products using X-ray diffraction, infrared spectroscopy, and scanning electron microscopy techniques. The characterization techniques suggested successful organic modifications of the smectite sample. The surfactant-modified smectite was the most efficient (66.9%)As removing adsorbent with a maximum adsorption capacity of 473.2 μg g−1. Kinetic study showed that the adsorbents reached As adsorption equilibrium within 3 h, and the data fitted reasonably well to power function and simple Elovich equations (R2 > 0.89). The adsorption data were explained well by the Freundlich and Sips isothermal models. The surfactant-modified and chitosan-grafted organoclays adsorbed As by electrostatic attraction and anion exchange, whereas the citric acid activated smectite followed ligand exchange and simple anion exchange mechanisms. This study thus demonstrated the potential of surfactant-modified clays in removing As from contaminated waters.
KW - Adsorption
KW - Arsenic
KW - Clay characterization
KW - Organic modification
KW - Smectite
KW - Water treatment
U2 - 10.1016/j.jhazmat.2019.05.053
DO - 10.1016/j.jhazmat.2019.05.053
M3 - Journal article
C2 - 31158581
AN - SCOPUS:85066269189
VL - 377
SP - 124
EP - 131
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
SN - 0304-3894
ER -