title: Highly stable and magnetically separable alginate/Fe3O4composite for the removal of strontium (Sr) from seawater.
abstract: In this study, a highly stable alginate/Fe3O4composite was synthesized, and systematically investigated for the practical application of strontium (Sr) removal in complex media, such as seawater and radioactive wastewater. To overcome the drawbacks of the use of alginate microspheres, high contents of alginic acid and Fe3O4were used to provide a more rigid structure with little swelling and facile separation, respectively. The synthesized composite was optimized for particle sizes of <400 μm and 1% content of Fe3O4. The alginate/Fe3O4composite showed excellent Sr uptake (≈400.0 mg/g) and exhibited outstanding selectivity for Sr among various cations (Na, Mg, Ca and K). However, in diluted Sr condition (50 mg/L), Ca significantly affected Sr adsorption, resulting in a decrease of Kdvalue from 3.7 to 2.4 at the 0.01 M Ca. The alginate/Fe3O4composite could be completely regenerated using 0.1 M HCl and CaCl2. In real seawater spiked with 50 mg/L of Sr, the alginate/Fe3O4composite showed 12.5 mg/g of Sr uptake, despite the highly concentrated ions in seawater. The adsorption experiment for radio-active90Sr revealed a removal efficiency of 67% in real seawater, demonstrating the reliability of the alginate/Fe3O4composite.
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Hong
authors.affiliation: Applied Quantum Composite Research Center, Korea Institute of Science and Technology (KIST), Eunha-ri San 101, Bongdong-eup, Wanju-gun, Jeollabuk-do 565-905, Republic of Korea.
authors.forename: Hyeon Su
authors.initials: HS
authors.lastname: Jeong
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: Byoung-Gyu
authors.initials: BG
authors.lastname: Kim
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: Jeongsik
authors.initials: J
authors.lastname: Hong
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: In-Su
authors.initials: IS
authors.lastname: Park
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: Taegong
authors.initials: T
authors.lastname: Ryu
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea.
authors.forename: Kang-Sup
authors.initials: KS
authors.lastname: Chung
authors.affiliation: Environmental Radioactivity Assessment Team, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, Republic of Korea.
authors.forename: Hyuncheol
authors.initials: H
authors.lastname: Kim
authors.affiliation: Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea. Electronic address: jryu@kigam.re.kr.
authors.forename: Jungho
authors.initials: J
authors.lastname: Ryu
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D008863:Microspheres; D010316:Particle Size; D015203:Reproducibility of Results; D012623:Seawater / Q000737:chemistry*; D013324:Strontium / Q000737:chemistry / Q000302:isolation & purification*; D013326:Strontium Radioisotopes / Q000737:chemistry / Q000378:metabolism*; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D000464:Alginates; D005290:Ferric Compounds; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D013324:Strontium; D013326:Strontium Radioisotopes; D062065:Wastewater; C000499:ferric oxide
keywords: Alginate; Iron oxide; Removal; Seawater; Strontium