Application of an ultrasonic field for the removal of selected pesticides

Abstract

The work detailed in this study investigated the efficiency of oxidizing technologie for the removal of organochlorine pesticides (OCPs) from aqueous solutions. OCPs constitute an important group of environmental pollutants also known to be endocrine-disrupting compounds (EDCs). The particular focus has been on a process achieving oxidation through the use of ultrasonic waves, with the impacts of pH, time on TOC and pesticide removal all being tested. Results confirm effective TOC decomposition using ultrasonic waves, albeit with reaction time showing a significant impact on results. Furthermore, results for TOC were not found to reflect those relating to the removal of individual substances from the tested mixture. Chromatographic analysis of reaction mixtures was therefore carried out after the selected processes had been applied, and an attempt to identify and characterize degradation products of the pesticides tested was also made. During the irradiation, the H2O2 concentration arising was also monitored. The results indicate that H2O2 is produced by cavitation during ultrasonic irradiation.