Kinetics of the bentazone herbicide ozonation

Abstract

The kinetics of ozonation of the herbicide Bentazone (3‐isopropyl‐lH‐2,1,3‐benzothiadiazin‐4–3H‐one 2,2 dioxide) is studied, the experiments being carried out in a bubble reactor, and using a porous plate as gas sparger. The increases of temperature, ozone partial pressure, initial Bentazone concentration and pH values under 5 have a positive effect on the degradation rate. A consumption of 2 moles of ozone per mol of herbicide degraded is determined for the direct reaction. Following a model based in the film theory which is applied to the experimental data, the reaction orders with respect to both, ozone and Bentazone, and the rate constants are evaluated for the herbicide ozonation.

Key words:

• Herbicide
• Bentazone
• ozonation
• kinetics
• rate constants

Notes

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