title: Water-soluble Fe3O4 nanoparticles with high solubility for removal of heavy-metal ions from waste water.
abstract: In this contribution, we synthesized water-soluble Fe(3)O(4) nanoparticles (NPs) with sufficiently high solubility (28 mg mL(-1)) and stability (at least one month) through a hydrothermal approach, and found that they exhibited excellent removal ability for heavy-metal ions from waste water. For the first time, the water-soluble Fe(3)O(4) NPs were used as adsorbents for heavy-metals removal from wastewater. It is noteworthy that the adsorption ability of the water-soluble Fe(3)O(4) NPs for Pb(2+) and Cr(6+) is stronger than water-insoluble Fe(3)O(4) NPs. Furthermore, the water-soluble Fe(3)O(4) NPs exhibited relatively high saturation magnetization (83.4 emu g(-1)), which allowed their highly-efficient magnetic separation from wastewater. The most important thing is that the water-soluble magnetite as an adsorbent can directly dissolve in water without the help of mechanical stirring or any extraneous forces, which may solve a key problem for the practical application of magnetic powders in the field of sewage purification. Moreover, the water-soluble Fe(3)O(4) NPs show a highly-efficient adsorption capacity for 10 ppm of Pb(2+) ions solution which can reach 90% within 2 minutes.
authors.affiliation: Key Laboratory of Automobile Materials, Ministry of Education and School of Materials Science and Engineering, Jilin University, Changchun 130022, China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Wang
authors.forename: Jianchen
authors.initials: J
authors.lastname: Li
authors.forename: Qing
authors.initials: Q
authors.lastname: Jiang
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhao