Degradation Kinetics of 2,4-D in Water Employing Hydrogen Peroxide and UV Radiation

Abstract

This paper reports the photooxidation of 2,4-dichlorophenoxyacetic acid (2,4-D) in aqueous solution employing hydrogen peroxide and ultraviolet radiation. The experimental work was performed in a batch, well-stirred tank reactor irradiated from its bottom. Herbicide degradation initial rates more than thirty times faster than those obtained employing only UV radiation were found. Two important aspects of the of the 2,4-D photodegradation reaction enhanced by H2O2 were studied: (i) effect on the rate of the H2O2/2,4-D initial molar ratio and (ii) effect on the rate of the irradiation power and, particularly, the characteristics of the wavelength distribution of the lamp output emission.