Degradation of Ethylene Thiourea (ETU) with Three Fenton Treatment Processes

Abstract

Anodic Fenton treatment (AFT), an electrochemical, hydroxyl radical oxidation treatment system, was developed for the degradation of aqueous pesticides and other aqueous organic wastes. AFT of ethylene thiourea (ETU) was optimized and compared with electrochemical Fenton treatment (EFT) and classic Fenton treatment (CFT). ETU is a known carcinogen and is an impurity and degradation product of the widely used ethylenebisdithiocarbamate (EBDC) fungicide group. ETU was degraded effectively in all treatment methods, with CFT being the most rapid; however, significant differences in degradation product profiles were noted over the course of treatments. AFT displayed the most efficient degradation of primary degradation products of ETU.

Degradation of paraquat herbicide by electrochemical advanced oxidation methods

“…As expected, it is noted that PQ and COD removal profiles during CFT showed rapid initial decrease followed by very slow removal rate. During CFT, the Fenton reactants were added all at once at the beginning of the treatment, in accordance with other investigations reported in the literature [68,69], leading to a rapid and efficient production of Å OH during the first minutes. However, due to quenching of Å OH through competitive parasitic reactions (with Fe 2+ and H 2 O 2 ), CFT has not a sustained hydroxyl radical production throughout the experiment, which limits the extent of PQ mineralization.…”

Degradation of methyl tertiary-butyl ether (MTBE) by anodic Fenton treatment

“…The non-acidic MTBE degradation products were not found to decrease in 60 min in this system in the control experiments without any Fenton reagent (data not shown); to explain this, more experiments would need to be conducted, which is beyond the scope of this work. Anodic Fenton treatment (AFT) used a half-cell technology developed in this laboratory and described by Saltmiras and Lemley [36]. The anode was made from cold rolled steel plates immersed in the aqueous MTBE solution.…”

“…Saltmiras and Lemley [36] developed a novel anodic Fenton treatment (AFT) system that allows the Fenton reaction to occur in an anodic half-cell. The cathode cell and anode cell were connected by a salt bridge.…”

Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment

“…These processes in situ generate the Fenton reagents (H 2 O 2 and/or Fe 2+ ) to yield OH • radicals [36,37]. The EF processes such as Fered-Fenton (EF-FeRe) [38,39], electrochemical peroxidation/anodic Fenton (EF-FeOx) [40][41][42], electro-Fenton (EF-H 2 O 2 -FeRe) [38,43], and peroxi-coagulation (EF-H 2 O 2 -FeOx) [44,45] increase the efficiency of pollutant degradation. The efficiency of pollutant degradation is enhanced when UV light or solar irradiation is used in combination with CF (photo-Fenton or solar photo-Fenton) and EF (photoelectro-Fenton or solar photoelectro-Fenton) processes.…”