Study on Apparent Kinetics of Photocatalytic Oxidation Degradation Rhodamine B by Photo-Fenton Reaction
LI Hong1,2,ZHENG Huai-li1*,LI Xiao-hong2,XIE Li-guo1,TANG Xue3
1. Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education,Chongqing University, Chongqing 400045, China 2. College of Resource and Environmental Science, Chongqing University,Chongqing 400044,China 3. College of Chemistry and Chemical Engineering,Chongqing University,Chongqing 400044,China
Abstract:The Fenton process, mixed by hydrogen peroxide and iron salts with highly oxidative effect, is recognized as one of powerful advanced oxidation technologies available and can be used to destroy a variety of persistent organic pollutants. The oxidation power of Fenton reagent is due to the generation of hydroxyl radical (·OH) during the iron catalysed decomposition of hydrogen peroxide in acid medium. The hydroxyl radical with a high oxidation potential (2.8 eV) attacks and completely destroys the pollutants in Fenton process. The degradation of pollutants can be considerably improved by using sunlight radiation, which is due to the generation of additional hydroxyl radicals. This photo-Fenton process had been effectively used to degrade the pollutants. In this paper, the definite quantity of Fenton reagent was added in the definite concentration of Rhodamine B solution. The degradation reaction was carried out at pH 3.5 under natural sunlight. The factors influencing on photocatalytic oxidation degradation rate of Rhodamine B were studied following: the initial concentration of Rhodamine B, initial concentrateions of Fe2+ and H2O2. The orders of degradation reaction were obtained by solving exponential kinetics equations of curve fitting, thereby gaining the kinetic parameters and reaction dynamics equation of the reaction system. The research contents included mainly: the UV-Vis spectra of Rhodamine B solution, the concentration-absorbency work curve of Rhodamine B solution, the analysis of the reaction system at various initial Rhodamine B concentrations, the analysis of the reaction system at various initial Fe2+concentrateions, the analysis of the reaction system at various initial H2O2 concentrations, and the calculation of the apparent kinetics parameters in reaction dynamics equation. The reaction dynamics equation from experiments was constructed: V=5×10-9P1.28F0.366E0.920, and overall reaction order was 2.57.
李宏1,2,郑怀礼1*,李晓红2,谢礼国1,唐雪3 . 光助Fenton反应催化氧化降解罗丹明B表观动力学研究[J]. 光谱学与光谱分析, 2008, 28(11): 2644-2648.
LI Hong1,2,ZHENG Huai-li1*,LI Xiao-hong2,XIE Li-guo1,TANG Xue3 . Study on Apparent Kinetics of Photocatalytic Oxidation Degradation Rhodamine B by Photo-Fenton Reaction. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2008, 28(11): 2644-2648.