Photo-Fenton degradation of the insecticide esfenvalerate in aqueous medium using a recirculation flow-through UV photoreactor

► The photo-Fenton reaction provides an efficient process by which to degrade esfenvalerate in aqueous suspensions. ► Photo-Fenton oxidation with Fe3+ is more efficient in degrading esfenvalerate than the Fe2+-based reaction. ► Esfenvalerate was degraded most efficiently by photo-Fenton reaction in the presence of 5 mM Fe3+ complex and 25 mM hydrogen peroxide at pH 2.5. ► The degradation of esfenvalerate by photo-Fenton (Fe3+) generates organic by-products. ► Organic compounds present in commercial esfenvalerate-based insecticides affect the degradation process.