title: Advanced kinetic model of the Cr(VI) removal by biomaterials at various pHs and temperatures.
abstract: Recently, a new and simple kinetic model was derived from a basic concept of the redox reaction between Cr(VI) and biomaterials, and successfully described the removal behavior of Cr(VI) under various Cr(VI) and biomaterial concentrations. However, this model did not consider the effects of pH and temperature on the Cr(VI) removal by biomaterials. In this study, a new efficient biomaterial, pine needle, capable of removing Cr(VI) was used as a model one to study the Cr(VI) removal by biomaterials. Analysis of chromium species in aqueous and solid phases revealed that the removal mechanism of Cr(VI) by pine needle was its reduction into Cr(III). The removal rate of Cr(VI) increased with a decrease in pH or with an increase of temperature. Finally, an advanced kinetic model in the form of -d[Cr(VI)]/dt = Ae(Ea/RT)[H+]n[Cr(VI)][OCs] was derived, and successfully predicted the time-dependent Cr(VI) concentration at various pHs (2-4) and temperatures (10-55 degrees C).
authors.affiliation: Advanced Environmental Biotechnology Research Center, Department of Chemical Engineering, School of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang 790-784, South Korea.
authors.forename: Donghee
authors.initials: D
authors.lastname: Park
authors.forename: Yeoung-Sang
authors.initials: YS
authors.lastname: Yun
authors.forename: Hae Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Jong Moon
authors.initials: JM
authors.lastname: Park
mesh_terms: D001709:Biotechnology; D002857:Chromium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D028223:Pinus; D018515:Plant Leaves; D013696:Temperature
chemical_list: D002857:Chromium