title: Arsenate removal with 3-mercaptopropanoic acid-coated superparamagnetic iron oxide nanoparticles.
abstract: In the present work, superparamagnetic iron oxide nanoparticles (SPION) surface-coated with 3-mercaptopropanoic acid (3-MPA) were prepared and their feasibility for the removal of arsenate from dilute aqueous solutions was demonstrated. The synthesized 3-MPA-coated SPION was characterized using transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infra-red spectrometry (FTIR). Separation efficiency of the coated nanoparticles and the equilibrium isotherm of arsenate adsorption were investigated. The obtained results reveal the arsenate adsorption to be highly pH-dependent, and the maximum adsorption was attained in less than 60 min. The resulting increase of 3-MPA-coated SPION adsorption capacity to twice the adsorption capacity of SPION alone under the same conditions is attributed to the increase of active adsorption sites. An adsorption reaction is proposed. On the other hand, efficient recovery of arsenate from the loaded nanoparticles was achieved using nitric acid (HNO3) solution, which also provides a concentration over the original arsenate solution.
authors.affiliation: Universitat Autònoma de Barcelona, Centre GTS, Department of Chemistry, 08193 Bellaterra (Barcelona), Spain. Electronic address: Diego.morillo.martin@gmail.com.
authors.forename: D
authors.initials: D
authors.lastname: Morillo
authors.affiliation: Royal Institute of Technology (KTH), Functional Materials Division, 16440 Kista (Stochkolm), Sweden. Electronic address: salam@kth.se.
authors.forename: A
authors.initials: A
authors.lastname: Uheida
authors.affiliation: Universitat Autònoma de Barcelona, Centre GTS, Department of Chemistry, 08193 Bellaterra (Barcelona), Spain. Electronic address: Gustavo.perez@uab.es.
authors.forename: G
authors.initials: G
authors.lastname: Pérez
authors.affiliation: Royal Institute of Technology (KTH), Functional Materials Division, 16440 Kista (Stochkolm), Sweden. Electronic address: mamoun@kth.se.
authors.forename: M
authors.initials: M
authors.lastname: Muhammed
authors.affiliation: Universitat Autònoma de Barcelona, Centre GTS, Department of Chemistry, 08193 Bellaterra (Barcelona), Spain. Electronic address: manuel.valiente@uab.cat.
authors.forename: M
authors.initials: M
authors.lastname: Valiente
keywords: 3-Mercaptopropionic acid; Arsenate removal; SPION; Superparamagnetic iron oxide nanoparticles