Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton ProcessReport as inadecuate




Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton Process - Download this document for free, or read online. Document in PDF available to download.

In this work, the degradation of 2-chloro-4,6-diamino-1,3,5-triazine in aqueous solutions by photo-Fenton process has been investigated. The preliminary results have shown that the degradation of 2-chloro-4,6-diamino-1,3,5-triazine by photo-Fenton process is more rapid and more effective than Fenton and UV-H2O2 processes. The effects of certain experimental parameters on kinetics and efficiency of the degradation of 2-chloro-4,6,-diamino-1,3,5-triazine by photo-Fenton process, have been evaluated. Under optimal conditions, photo-Fenton process achieved more than 90% of chloride release and about 30% of nitrate formation. The results of total organic carbon TOC and total Kjeldahl nitrogen TKN analyses have shown that no carbon dioxide and ammonia are formed during photo-Fenton treatment of aqueous solutions containing 40 mg-L triazine. These results indicate that only substituent groups of triazine ring are released; however, nitrogen atoms of triazine ring remain unaffected. A simple mechanism of degradation of 2-chloro-4,6-diamino-1,3,5-triazine has been proposed. The degradation starts by a rapid release of chlorine atoms as chloride ions to form 2-hydroxy-4,6-diamino-1,3,5-triazine. The amino groups of 2-hydroxy-4,6-diamino-1,3,5-triazine undergo are oxidized into nitro groups by hydroxyl radicals to form 2-hydroxy-4,6-dinitro-1,3,5-triazine which undergoes a slow release of nitro groups and their substitution with hydroxyl groups to form cyanuric acid and nitrate ions. The degradation of cyanuric acid by photo-Fenton process has also been investigated. The results of TOC and TKN analyzes show that no carbon dioxide is formed during the treatment.

KEYWORDS

Photo-Fenton Process, Hydroxyl Radicals, s-Triazine Herbicides, Degradation, Cyanuric Acid

Cite this paper

Dbira, S. , Bedoui, A. and Bensalah, N. 2014 Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton Process. American Journal of Analytical Chemistry, 5, 500-517. doi: 10.4236-ajac.2014.58059.





Author: Sondos Dbira, Ahmed Bedoui, Nasr Bensalah

Source: http://www.scirp.org/



DOWNLOAD PDF




Related documents