title: Removal of Cr(VI) by magnetite nanoparticle.
abstract: Magnetite nanoparticles were synthesized by sol-gel method. The highly crystalline nature of the magnetite structure with diameter of around 10 nm was characterized with transmission electron microscopy and X-ray diffractometry. The surface area was determined to be 198 m2/g. Batch experiments were carried out to determine the adsorption kinetics and mechanism of Cr(VI) by these magnetite nanoparticles. The Cr(VI) uptake was mainly governed by physico-chemical adsorption. The adsorption process was found to be pH and temperature dependent. The adsorption data fit well with the Freundlich isotherm equation. The Freundlich constants were calculated at different temperatures. The adsorption capacity increased with rising temperature. Preliminary results indicate that magnetite nanoparticles may be used as an adsorbent for removal of Cr(VI) from wastewater.
authors.affiliation: Environmental Engineering Program, School of Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: J
authors.initials: J
authors.lastname: Hu
authors.forename: I M C
authors.initials: IM
authors.lastname: Lo
authors.forename: G
authors.initials: G
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D002857:Chromium / Q000302:isolation & purification*; D004563:Electrochemistry; D052203:Ferrosoferric Oxide; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D019216:Metals, Heavy / Q000302:isolation & purification; D008854:Microscopy, Electron; D036103:Nanotechnology; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D013696:Temperature; D013816:Thermodynamics; D014865:Waste Disposal, Fluid / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D019216:Metals, Heavy; D010087:Oxides; D002857:Chromium; C074702:chromium hexavalent ion; D007501:Iron; D052203:Ferrosoferric Oxide