Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10562927 | Talanta | 2005 | 6 Pages |
Abstract
This work proposes a spectrophotometric method for the determination of hydrogen peroxide during photodegradation reactions. The method is based on the reaction of H2O2 with amonium metavanadate in acidic medium, which results in the formation of a red-orange color peroxovanadium cation, with maximum absorbance at 450 nm. The method was optimized using the multivariate analysis providing the minimum concentration of vanadate (6.2 mmol Lâ1) for the maximum absorbance signal. Under these conditions, the detection limit is 143 μmol Lâ1. The reaction product showed to be very stable for samples of peroxide concentrations up to 3 mmol Lâ1 at room temperature during 180 h. For higher concentrations however, samples must be kept refrigerated (4 °C) or diluted. The method showed no interference of Clâ (0.2-1.3 mmol Lâ1), NO3â (0.3-1.0 mmol Lâ1), Fe3+ (0.2-1.2 mmol Lâ1) and 2,4-dichlorophenol (DCP) (0.2-1.0 mmol Lâ1). When compared to iodometric titration, the vanadate method showed a good agreament. The method was applied for the evaluation of peroxide consumption during photo-Fenton degradation of 2,4-dichlorophenol using blacklight irradiation.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Raquel F. Pupo Nogueira, Mirela C. Oliveira, Willian C. Paterlini,