Degradation of the Insecticides Thiamethoxam and Imidacloprid in Aqueous Solution as Promoted by an Innovative Fe-o/Fe3O4 Composite

The performance of an innovative Fe-o/Fe3O4 composite to degrade the insecticides Thiamethoxam and Imidacloprid in aqueous solution was evaluated. Factorial designs were built to investigate the influence of a number of crucial variables on such degradation processes: H2O2 concentration, solution pH, and composite mass. The solution pH was the most influential variable; hence, significant degradation rates (> 90%) was accomplished exclusively in acidic solutions (pH=2). In addition, the composite was highly efficient in promoting the degradation of both insecticides either in the presence or unpredictably in the absence of H2O2. These results thus indicated that the composite possess a dual behavior, acting as either an oxidizing or a reducing agent.