An, Byungryul Lee, Healim Lee, Soonjae Lee, Sang-Hyup Choi, Jae-Woo 2024-01-20T06:00:48Z 2024-01-20T06:00:48Z 2021-09-03 2015-11 0304-3894 https://pubs.kist.re.kr/handle/201004/124859 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 4 h, and equilibrium was attained in 48 h. 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 0.13 mmol/g, respectively. The separation factor (a) values for alpha(Pb/Cu), alpha(Pb/Ni), and alpha(Cu/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. (C) 2015 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE BV Determining the selectivity of divalent metal cations for the carboxyl group of alginate hydrogel beads during competitive sorption Article 10.1016/j.jhazmat.2015.05.005 1 JOURNAL OF HAZARDOUS MATERIALS, v.298, pp.11 - 18 JOURNAL OF HAZARDOUS MATERIALS 298 11 18 N scie scopus 000360595800002 2-s2.0-84929332052 Engineering, Environmental Environmental Sciences Engineering Environmental Sciences & Ecology Article CALCIUM ALGINATE AQUEOUS-SOLUTION HEAVY-METALS KINETIC-ANALYSIS CADMIUM REMOVAL ADSORPTION IONS CHITOSAN EQUILIBRIUM BIOSORPTION Sorption Carboxyl group Competition Heavy metal Selectivity