title: A novel technology for biosorption and recovery hexavalent chromium in wastewater by bio-functional magnetic beads.
abstract: The goal of this study was to develop an applied technique for the removal and recovery of heavy metal in wastewater. It is novel that the Cr(VI) could be adsorbed and recovered by bio-functional magnetic beads. Furthermore, the magnetic separation technology would make their separation more convenient. The beads were constituted by the powder of Rhizopus cohnii and Fe(3)O(4) particles coated with alginate and polyvinyl alcohol (PVA). The parameters effecting Cr(VI) removal were obtained: the optimum pH 1.0 and optimum temperature 28 degrees C. The biosorption took place mainly in form of Cr(VI) and R. cohnii biomass played a key role in Cr(VI) adsorption. The model of Langmuir isotherm and Lagergren could be better used to fit the sorption process and kinetics, respectively. The beads still maintained predominant characteristics of adsorption, recovery and magnetism after five cycles for adsorption-desorption. The mechanism of adsorption was gained by Fourier transform infrared spectroscopy (FTIR), raman spectroscopy (RS) and scanning electron microscopy (SEM). The groups of -NH(3)(+), -NH(2)(+)-, and NH- played an important role in the Cr(VI) adsorption. Consequently, the beads exhibited the superior performances in Cr(VI) cleanup, separation and recovery and the perspective potential in application.
authors.affiliation: Department of Microbiology, College of Life Science, Hunan Normal University, Changsha 410081, People's Republic of China.
authors.forename: Huidong
authors.initials: H
authors.lastname: Li
authors.forename: Zhao
authors.initials: Z
authors.lastname: Li
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.forename: Xiao
authors.initials: X
authors.lastname: Xiao
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Peng
authors.forename: Le
authors.initials: L
authors.lastname: Deng
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry; D002857:Chromium / Q000302:isolation & purification*; D005290:Ferric Compounds / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008280:Magnetics; D008855:Microscopy, Electron, Scanning; D011142:Polyvinyl Alcohol / Q000737:chemistry; D012233:Rhizopus / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013696:Temperature; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D000464:Alginates; D005290:Ferric Compounds; D006603:Hexuronic Acids; D014874:Water Pollutants, Chemical; D002857:Chromium; C000499:ferric oxide; D020723:Glucuronic Acid; D011142:Polyvinyl Alcohol