Kinetics of microwave-enhanced oxidation of phenol by hydrogen peroxide  

作　　者：Deming ZHAO Jie CHENG Michael R.HOFFMANN 

机构地区：[1]College of Chemical Engineering and Materials Science,Zhejiang University of Technology,Hangzhou 310032,China [2]W.M.Keck Laboratories,California Institute of Technology,Pasadena,CA 91125,USA

出　　处：《Frontiers of Environmental Science & Engineering》2011年第1期57-64,共8页环境科学与工程前沿（英文）

基　　金：This research was supported by Hong Kong General Research Fund(HKU7195/06E);the authors would like to thank HKU Faculty of Engineering to support Dr.X.X.Zhang with the PostDoctor;This work was supported by the China Postdoctoral Science Foundation Funded Project(Grant No.20100471716);Zhejiang Provincial Natural Science Foundation of China(Grant No.Y5100075)

摘　　要：Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave(MW)irradiation.A simple kinetic model for the overall degradation of phenol in the presence of excess H_(2)O_(2) is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and H_(2)O_(2).A detailed parametric study showed that the degradation rate of phenol increased with increasing[H_(2)O_(2)]until saturation was observed.Phenol degradation followed apparent zero-order kinetics under MW radiation or H_(2)O_(2) oxidation.However,after 90 min of irradiation,the observed kinetics shifted to pseudo first order.The overall reaction rates were significantly enhanced in the combined MW/H_(2)O_(2) system,mainly because microwave could accelerate H_(2)O_(2) to generate hydroxyl radical(·OH)and other reactive oxygen intermediates.The observed synergetic effects of the MW/H_(2)O_(2) process resulted in an increased in the net reaction rate by a factor of 5.75.When hydrogen peroxide is present in a large stoichiometric excess,the time required to achieve complete mineralization is reduced significantly.

关 键 词：microwave(MW)irradiation hydrogen peroxide PHENOL synergetic effects kinetic model 

分 类 号：O64[理学—物理化学]