title: Degradation and formation of wood odorant β-cyclocitral during permanganate oxidation.
abstract: The effect of permanganate oxidation on the formation and degradation of wood odorant β-cyclocitral in water was investigated. Oxidation experiments were conducted for β-cyclocitral prepared from pure chemicals and extracted from Microcystis aeruginosa. The data were simulated with appropriate kinetic rate models. The formation and degradation of β-cyclocitral during the oxidation of β-carotene were also monitored and modeled. The degradation of β-cyclocitral prepared from pure chemicals followed second-order kinetics with a rate constant of 91.7 ± 2.4M(-1)s(-1), and that of the β-cyclocitral precursor, β-carotene, followed first-order kinetics with a rate constant of 0.0054 ± 0.0004 min(-1). During the oxidation of β-carotene, β-cyclocitral was produced. The formation and degradation can both be simulated by first-order kinetics with respect to β-carotene and β-cyclocitral concentrations, respectively. The degradation rate of β-cyclocitral produced from β-carotene was found to be much slower than that for β-cyclocitral obtained from pure chemicals, very likely due to a mass transfer limitation. The kinetic models were further employed to simulate the oxidation of β-cyclocitral in the presence of β-carotene and for β-cyclocitral extracted from M. aeruginosa, respectively. The models well predict/fit the experimental data, with rate constants similar to other experiments, indicating that the models may be used for simulating the formation and degradation of β-cyclocitral in water treatment systems.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai City 200092, China.
authors.forename: Ke-jia
authors.initials: KJ
authors.lastname: Zhang
authors.forename: Nai-yun
authors.initials: NY
authors.lastname: Gao
authors.forename: Hung-Kai
authors.initials: HK
authors.lastname: Yen
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Chiu
authors.forename: Tsair-Fuh
authors.initials: TF
authors.lastname: Lin
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D004224:Diterpenes / Q000737:chemistry*; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D046931:Microcystis / Q000737:chemistry; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D014934:Wood; D019207:beta Carotene / Q000737:chemistry
chemical_list: D000447:Aldehydes; D004224:Diterpenes; D017895:Manganese Compounds; D010087:Oxides; D019207:beta Carotene; C048856:permanganic acid; C516118:beta-cyclocitral