Iron(II)-catalyzed enhancement of ultrasonic-induced degradation of diethylstilbestrol (DES)

Abstract

The oxidation of the endocrine disruptor, diethylstilbestrol (DES) in aqueous media by ultrasound is significantly enhanced by Fe(II) catalyst. The observed enhancement is likely the result of increased levels of hydroxyl radicals from the iron-promoted reduction of the hydrogen peroxide produced during ultrasonic irradiation. The degradation is effective over a range of concentrations and is consistent with pseudo first-order kinetics. Relatively high concentrations of hydrogen peroxide, $450 mM, are present in solution under our experimental conditions after 1 h of ultrasonic irradiation (665 kHz). The concentration of H 2 O 2 in solution decreased with the addition of Fe(II) along with an increase in the degradation of DES. Hydrogen peroxide alone does not appreciably degrade DES. Our results demonstrate ultrasonicinduced degradation of DES can be accelerated with the addition of Fe(II). The combination of ultrasonic irradiation and Fe(II)-promoted conversion of H 2 O 2 to hydroxyl radical may provide a valuable strategy for the treatment of organic pollutants. #

Mechanism of the enhanced degradation of pentachlorophenol by ultrasound in the presence of elemental iron

“…During aque- ous ultrasonic irradiation, water can be subjected to pyrolysis and generates hydroxyl radicals. The catalysis of Fe(II) in ultrasound system was confirmed by Abderrazik et al [25] and Nam et al [26]. It was reported that the partial recombination of hydroxyl radicals would result in the formation of hydrogen peroxide (H 2 O 2 ) in ultrasound system, and the H 2 O 2 production decreased by the addition of Fe(II), due to the reaction of Fe(II) with H 2 O 2 (Fenton's reaction).…”

Degradation of C.I. Acid Orange 7 by ultrasound enhanced heterogeneous Fenton-like process

“…The promising results have been reported when the coupling of Fenton's reagent with ultrasonic irradiation (named sono-Fenton process) was used to the decomposition of chlorinated aromatic * Corresponding author. hydrocarbons [5], endocrine disruptors [6,7], anionic surfactants [8], 2,4-dinitrophenol [9], EDTA [10], MTBE [11], and dyes [12,13]. Like classical Fenton process, the use of homogeneous iron catalysts leads to the ferric hydroxide sludge during neutralization stage of sono-Fenton process, which requires additional separation and disposal [3].…”

Isolation and characterization of Pseudomonas sp. strain capable of degrading diethylstilbestrol

“…AOPs that had been developed to degrade DES, included ultrasonic-induced degradation, electrochemical degradation, photooxidation degradation, UV-light-inducing photodegradation, and ozonation (Abderrazik et al 2005;Korshin et al 2006;Lin et al 2009;You et al 2006;Zhou et al 2004). Although these methods could effectively remove DES from the environments, the whole processes needed specific cells in site, such as cells with ultrasound sample, PbO 2 anode, and stainless steel cathode, or certain equipment including highpressure mercury lamp and ozone generator.…”