Kinetics of the chemical degradation of diuron.
The influence of pH and buffer concentration on the chemical degradation of diuron in water has been analysed over a wide temperature range. The process irreversibly gives 3,4-dichloroaniline as the only product containing the phenyl ring. H+, OH- and phosphate buffer are efficient catalysts of the reaction. The rate constant first increases rapidly at low buffer concentrations and then gradually levels off at higher ones. At 40 degrees C and high phosphate concentration (>0.01 M), or in the extreme pH regions, the half-life is approximately 4 months and the activation energy is 127 +/- 2 kJmol(-1).
Dipartimento di Scienze Ambientali, Seconda Università di Napoli, Caserta, Italy.
Stefano
S
Salvestrini
Paola
P
Di Cerbo
Sante
S
Capasso
D004237:Diuron / Q000737:chemistry*; D006207:Half-Life; D006540:Herbicides / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D010671:Phenylurea Compounds; D014873:Water Pollutants / Q000032:analysis*
D006540:Herbicides; D010671:Phenylurea Compounds; D014873:Water Pollutants; D004237:Diuron