Degradation of Diuron Photoinduced by Iron(III) in Aqueous Solution

✍ Scribed by Mazellier, Patrick; Jirkovsky, Jaromir; Bolte, Michèle

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 447 KB
• Volume: 49
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199703)49:3<259::aid-ps526>3.0.co;2-h

✦ Synopsis

The degradation of diuron photoinduced by iron(III) in aqueous solution has been investigated with di †erent iron(III) species (monomeric species Fe(OH)2, dimeric species and water-soluble oligomeric species) Fe 2 (OH) 2 4ù nder monochromatic excitation at 365 nm and under sunlight. The rate of degradation depends on the concentration in Fe(OH)2, the most reactive species in terms of radical formation. The major photoproduct is 3-(3,4-dichloro-~OH phenyl)-1-formyl-1-methylurea which represents more than 60% of diuron disappearance. The mechanism only involves the attack by radicals arising from ~OH iron(III) excited species. The half-lives of diuron when submitted to such a process in the environment were estimated to be 1È2 h and a few days according to the concentration of Fe(OH)2`(respectively 70% and \10% of total iron(III) concentration).