Analytical studies on degradation mechanism of herbicide 4-chlorophenoxyacetic acid in water by gamma/H₂O₂ and gamma/ozone processes

ABSTRACT

Radiolytic degradation of 4-chlorophenoxyacetic acid was followed in the presence of hydrogen peroxide and ozone. The synergic effect of ozone is found to be relatively high since the amounts of detected aromatic intermediates are lower as well as the amounts of small aliphatic acids are higher. Chloride ions are one of the most important mineralization products and splitted with a yield of more than 80%. The amounts of small aliphatic acids formed in the last step before mineralization (oxalic, acetic and formic acid) were followed and their formation from 4-chlorophenoxyacetic acid was confirmed. Dissolved oxygen was consumed to form reactive radicals during irradiation. Product analysis and confirmation are followed by gas chromatography/mass spectrometry and ion chromatography. The degradation path of 4-chlorophenoxyacetic acid was suggested with determined intermediates.

KEYWORDS:

• 4-chlorophenoxyacetic acid
• radiolytic degradation
• ozone
• degradation path
• advanced oxidation processes

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors would like to thank Hacettepe University Scientific Research Projects Coordination Unit for financial support through project no: 07A601001.