title: Oxidation of unsaturated carboxylic acids under hydrothermal conditions.
abstract: Hydrothermal oxidation pathways of high molecular weight unsaturated carboxylic acids were investigated for the potential use of chemoselectivity to improve the efficiency of the desired products from biomasses directly containing or easily producing unsaturated carboxylic acids. Hock cleavage, which frequently occur at general chemical, was observed in the absence of any acid catalyst and may be a potential major oxidation cleavage mechanism, which leads to the cleavage at both the carbon-carbon double bond and the single bond near a double bond. The addition of a peroxyl radical to the double bond may be also a potential major oxidation mechanism, which leads to the oxidation cleavage mainly at the carbon-carbon double bond. Cleavage at the carbon-carbon bond near the double bond by the addition of a peroxyl radical to the double bond may also occur. However, oxidation at either alpha-, beta-, or gamma-carbon to the -COOH group hardly occurred. These results may help to selectively produce desired products from biomasses, such as lignin and oils.
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China. fmjin@tongji.edu.cn
authors.forename: Fangming
authors.initials: F
authors.lastname: Jin
authors.forename: Heng
authors.initials: H
authors.lastname: Zhong
authors.forename: Jianglin
authors.initials: J
authors.lastname: Cao
authors.forename: Jianxun
authors.initials: J
authors.lastname: Cao
authors.forename: Kohei
authors.initials: K
authors.lastname: Kawasaki
authors.forename: Astushi
authors.initials: A
authors.lastname: Kishita
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Tohji
authors.forename: Heiji
authors.initials: H
authors.lastname: Enomoto
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D004951:Esterification; D008401:Gas Chromatography-Mass Spectrometry; D006586:Hexanes / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D008970:Molecular Weight; D019301:Oleic Acid / Q000737:chemistry*; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D006586:Hexanes; D010545:Peroxides; D014867:Water; C026385:n-hexane; D019301:Oleic Acid; C049375:perhydroxyl radical; D017665:Hydroxyl Radical; D006859:Hydrogen