Yoon, Seo-Young Lee, Chang-Gu Park, Jeong-Ann Kim, Jae-Hyun Kim, Song-Bae Lee, Sang-Hyup Choi, Jae-Woo 2024-01-20T10:34:38Z 2024-01-20T10:34:38Z 2021-09-05 2014-01 1385-8947 https://pubs.kist.re.kr/handle/201004/127267 Phosphate (P) removal by magnetic iron oxide nanoparticles was investigated using kinetic, equilibrium and thermodynamic experiments. The results demonstrate that phosphate sorption to the magnetic nanoparticles reached equilibrium at 24 h with the maximum sorption capacity of 5.03 mg P g(-1) under given experimental conditions (initial P concentration range = 2-20 mg P L-1; adsorbent dose = 0.6 g L-1; reaction time = 24 h). The phosphate removal was relatively constant at an acidic solution pH (3.0-3.1 mg P g(-1), at pH 2.0-6.0), whereas the phosphate removal decreased sharply as the solution pH approached a highly alkaline condition (0.33 mg P g(-1) at pH 11.1). Thermodynamic tests indicate that phosphate sorption to the magnetic nanoparticles increased with increasing temperature from 15 to 45 degrees C, indicating the spontaneous and endothermic nature of sorption process (Delta H-0 = 39.17 kJ mol(-1); Delta S-0 = 156.35 J K-1 mol(-1); Delta G(0) = -5.88 similar to -10.57 kJ mol(-1)). The results indicate that the pseudo second-order model was most suitable for describing the kinetic data. Regarding the equilibrium data, the Freundlich and Redlich-Peterson isotherms were fitted well. This study demonstrates that magnetic iron oxide nanoparticles could be used for phosphate removal from aqueous solutions with regeneration and repeated use. (C) 2013 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE SA Kinetic, equilibrium and thermodynamic studies for phosphate adsorption to magnetic iron oxide nanoparticles Article 10.1016/j.cej.2013.09.053 1 CHEMICAL ENGINEERING JOURNAL, v.236, pp.341 - 347 CHEMICAL ENGINEERING JOURNAL 236 341 347 N scie scopus 000328801100037 2-s2.0-84886668889 Engineering, Environmental Engineering, Chemical Engineering Article REMOVAL SURFACE Magnetic iron oxide nanoparticles Phosphate Adsorption Magnetic separation