TY - JOUR
T1 - Determining the selectivity of divalent metal cations for the carboxyl group of alginate hydrogel beads during competitive sorption
AU - An, Byungryul
AU - Lee, Healim
AU - Lee, Soonjae
AU - Lee, Sang Hyup
AU - Choi, Jae Woo
N1 - Funding Information:
This work was supported by Nano-Convergence Foundation ( www.nanotech2020.org ) funded by the Ministry of Science , ICT and Future Planning (MSIP, Korea) & the Ministry of Trade, Industry and Energy (MOTIE, Korea) [Project Number: R201400210] and the Korea Institute of Science and Technology (KIST) institutional program (2E25311).
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/11/5
Y1 - 2015/11/5
N2 - To investigate the competitive sorption of divalent metal ions such as Ca2+, Cu2+, Ni2+, and Pb2+ on alginate hydrogel beads, batch and column tests were conducted. The concentration of carboxyl group was found to be limited in the preparation of spherical hydrogel beads. From kinetic test results, 80% of sorption was observed within 4h, and equilibrium was attained in 48h. According to the comparison of the total uptake and release, divalent metal ions were found to stoichiometrically interact with the carboxyl group in the alginate polymer chain. From the Langmuir equation, the maximum capacities of Pb2+, Cu2+, and Ni2+ were calculated to be 1.1, 0.48, and 0.13mmol/g, respectively. The separation factor (α) values for αPb/Cu, αPb/Ni, and αCu/Ni were 14.0, 98.9, and 7.1, respectively. The sorption capacity of Pb2+ was not affected by the solution pH; however, the sorption capacities of Cu2+ and Ni2+ decreased with increasing solution pH, caused by competition with hydrogen. According to the result from the fixed column test, Pb2+ exhibited the highest affinity, followed by Cu2+ and Ni2+, which is in exact agreement with those of kinetic and isotherm tests. The sorbent could be regenerated using 4% HCl, and the regenerated sorbent exhibited 90% capacity upto 9 cycles.
AB - To investigate the competitive sorption of divalent metal ions such as Ca2+, Cu2+, Ni2+, and Pb2+ on alginate hydrogel beads, batch and column tests were conducted. The concentration of carboxyl group was found to be limited in the preparation of spherical hydrogel beads. From kinetic test results, 80% of sorption was observed within 4h, and equilibrium was attained in 48h. According to the comparison of the total uptake and release, divalent metal ions were found to stoichiometrically interact with the carboxyl group in the alginate polymer chain. From the Langmuir equation, the maximum capacities of Pb2+, Cu2+, and Ni2+ were calculated to be 1.1, 0.48, and 0.13mmol/g, respectively. The separation factor (α) values for αPb/Cu, αPb/Ni, and αCu/Ni were 14.0, 98.9, and 7.1, respectively. The sorption capacity of Pb2+ was not affected by the solution pH; however, the sorption capacities of Cu2+ and Ni2+ decreased with increasing solution pH, caused by competition with hydrogen. According to the result from the fixed column test, Pb2+ exhibited the highest affinity, followed by Cu2+ and Ni2+, which is in exact agreement with those of kinetic and isotherm tests. The sorbent could be regenerated using 4% HCl, and the regenerated sorbent exhibited 90% capacity upto 9 cycles.
KW - Carboxyl group
KW - Competition
KW - Heavy metal
KW - Selectivity
KW - Sorption
UR - http://www.scopus.com/inward/record.url?scp=84929332052&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2015.05.005
DO - 10.1016/j.jhazmat.2015.05.005
M3 - Article
C2 - 25988716
AN - SCOPUS:84929332052
SN - 0304-3894
VL - 298
SP - 11
EP - 18
JO - Journal of hazardous materials
JF - Journal of hazardous materials
ER -