Radiation degradation of Congo Red in aqueous solution.
Radiation-induced degradation of Congo Red (an azo dye) in aqueous solution was studied both with steady-state radiolysis and time-resolve techniques of pulse radiolysis and laser flash photolysis. Decomposition and mineralization of Congo Red by gamma-rays was investigated with the changes of absorption spectra, degradation efficiency, TOC removal and pH changes of the solutions in different irradiation systems. The main radiolytic products resulting from steady-state radiolysis of Congo Red were examined by HPLC and LC-MS. Complete degradation of Congo Red was observed at different absorbed doses under diverse irradiation condition. The TOC removal of the solutions saturated with O2 or N2O reached 76% and 86% at the absorbed dose of 11.9 kGy, respectively. Pulse radiolysis and laser flash photolysis experiments were carried out to study the reaction of Congo Red with e(aq)- and ()OH. The reaction rate constants were determined.
Ma
Hongjuan
H
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, PR China.
Wang
Min
M
Yang
Ruiyuan
R
Wang
Wenfeng
W
Zhao
Jun
J
Shen
Zhongqun
Z
Yao
Side
S
D003224:Congo Red / Q000737:chemistry / Q000528:radiation effects*; D005720:Gamma Rays; D007220:Industrial Waste; D007700:Kinetics; D009584:Nitrogen / Q000737:chemistry; D009609:Nitrous Oxide / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000737:chemistry*; D013053:Spectrophotometry; D013783:Textile Industry; D014865:Waste Disposal, Fluid / Q000379:methods*; D020002:tert-Butyl Alcohol / Q000737:chemistry
D007220:Industrial Waste; D017382:Reactive Oxygen Species; D003224:Congo Red; D009609:Nitrous Oxide; D020002:tert-Butyl Alcohol; D009584:Nitrogen; D010100:Oxygen