TY - JOUR
T1 - Assessment and optimization of As(V) adsorption on hydrogel composite integrating chitosan-polyvinyl alcohol and Fe3O4 nanoparticles and evaluation of their regeneration and reusable capabilities in aqueous media
AU - Weerasundara, Lakshika
AU - Ok, Yong Sik
AU - Kumarathilaka, Prasanna
AU - Marchuk, Alla
AU - Bundschuh, Jochen
N1 - Funding Information:
The authors acknowledge the support from Katelynn Hadzi at the University of Southern Queensland, Anya J. E. Yago, Dr. Craig Stoppiello and Dr. Lachlan Casey at the Centre for Microscopy and Microanalysis (CMM) at the University of Queensland.
Funding Information:
This work was supported by the University of Southern Queensland , QLD, Australia (RTP Stipend Scholarship programme).
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2023/1/10
Y1 - 2023/1/10
N2 - A modified chitosan-polyvinyl alcohol (PVA) hydrogel was developed by incorporating Fe3O4 nanoparticles. Four chitosan-Fe3O4 (ChFe) hydrogel types were developed based on chitosan:Fe3O4 ratio as 1:0, 1:1, 1:0.5 and 1:0.25. Batch sorption experiments were conducted with different pH, dosage, kinetics, and isotherms. The exhausted ChFe hydrogels were evaluated for their regeneration and reuse capability with different acids and bases. The best hydrogel for arsenic (V) [As(V)] adsorption was 1:0.5 ratio ChFe hydrogel. The highest As(V) adsorption (89 %) was at pH 4 and the adsorption capacity gradually decreased with increasing solution pH. Within the pH 4–6 range, the hydrogel surface became positively charged due to protonation of –NH2 and –OH groups in the polymer chain and the positive surface attracted H2AsO4− and HAsO42− oxyanions. The experimental kinetic data was well-fitted to the Elovich model (R2 of 0.99) while the Freundlich isotherm model best described the isotherm data (R2 of 0.97). The models predicted chemisorption mechanisms on ChFe hydrogel composites. Electrostatic attractions with –NH3+ and –OH2+, ligand-exchange inner-sphere complexes formation and bidentate corner-sharing (2C) and bidentate edge-sharing (2E) trimetric surface complexes formation have been proposed as the adsorption mechanism of As(V) into ChFe hydrogel. 0.1 M CH3COOH showed the best regeneration pattern with 75, 96, 81, 53 and 43 % of 1st, 2nd, 3rd, 4th and 5th adsorption respectively. Because of this re-usable capability, the As(V) adsorption capacity is not a single value from one adsorption cycle, but a cumulative value of several adsorption cycles and it was 17.39 mg/g for five adsorption cycles. Open for regeneration and reuse, no post-treatment is needed for adsorbent-water separation, allow applications of the ChFe hydrogel composite in a wide range of applications such as water filtration and purification systems. The modification with ChFe further expands the application capacity since the ChFe can remove other contaminants as well.
AB - A modified chitosan-polyvinyl alcohol (PVA) hydrogel was developed by incorporating Fe3O4 nanoparticles. Four chitosan-Fe3O4 (ChFe) hydrogel types were developed based on chitosan:Fe3O4 ratio as 1:0, 1:1, 1:0.5 and 1:0.25. Batch sorption experiments were conducted with different pH, dosage, kinetics, and isotherms. The exhausted ChFe hydrogels were evaluated for their regeneration and reuse capability with different acids and bases. The best hydrogel for arsenic (V) [As(V)] adsorption was 1:0.5 ratio ChFe hydrogel. The highest As(V) adsorption (89 %) was at pH 4 and the adsorption capacity gradually decreased with increasing solution pH. Within the pH 4–6 range, the hydrogel surface became positively charged due to protonation of –NH2 and –OH groups in the polymer chain and the positive surface attracted H2AsO4− and HAsO42− oxyanions. The experimental kinetic data was well-fitted to the Elovich model (R2 of 0.99) while the Freundlich isotherm model best described the isotherm data (R2 of 0.97). The models predicted chemisorption mechanisms on ChFe hydrogel composites. Electrostatic attractions with –NH3+ and –OH2+, ligand-exchange inner-sphere complexes formation and bidentate corner-sharing (2C) and bidentate edge-sharing (2E) trimetric surface complexes formation have been proposed as the adsorption mechanism of As(V) into ChFe hydrogel. 0.1 M CH3COOH showed the best regeneration pattern with 75, 96, 81, 53 and 43 % of 1st, 2nd, 3rd, 4th and 5th adsorption respectively. Because of this re-usable capability, the As(V) adsorption capacity is not a single value from one adsorption cycle, but a cumulative value of several adsorption cycles and it was 17.39 mg/g for five adsorption cycles. Open for regeneration and reuse, no post-treatment is needed for adsorbent-water separation, allow applications of the ChFe hydrogel composite in a wide range of applications such as water filtration and purification systems. The modification with ChFe further expands the application capacity since the ChFe can remove other contaminants as well.
KW - Adsorption
KW - Arsenic(V)
KW - Chitosan
KW - FeO nanoparticles
KW - Hydrogel
UR - http://www.scopus.com/inward/record.url?scp=85138999466&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2022.158877
DO - 10.1016/j.scitotenv.2022.158877
M3 - Article
C2 - 36150591
AN - SCOPUS:85138999466
SN - 0048-9697
VL - 855
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 158877
ER -