Degradation of organic molecules in advanced oxidation processes: Relation between chemical structure and degradability

Homlok, Renáta; Takács, Erzsébet; Wojnárovits, László

doi:10.1016/j.chemosphere.2012.11.073

Cited by 33 publications

(10 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1.2. The value is much higher than the ratio established for fenuron, ~0.7 [ 11 ] and it is also higher than found for the majority of molecules studied so far in our laboratory (0.25 − 1.0 [ 17 - 19 ]). The high ratio in the present study indicates effective diuron degradation in air saturated solution.…”

Section: Discussioncontrasting

confidence: 60%

Ionizing radiation induced degradation of diuron in dilute aqueous solution

Kovács

Mile

et al. 2015

Chemistry Central Journal

Self Cite

View full text Add to dashboard Cite

BackgroundCutting edge technologies based on Advanced Oxidation Processes (AOP) are under development for the elimination of highly persistent organic molecules (like pesticides) from water matrices. Among them, ionizing radiation treatment represents a promising technology that requires no additives and can be easily adapted to an industrial scale. In these processes several reactive species are produced, mainly powerful oxidizing radicals inducing the degradation. This paper investigates the reactions taking place in dilute aqueous solutions of a hazardous pollutant (diuron) during irradiation.ResultsIrradiation of aqueous diuron solutions resulted in effective degradation of the solute mainly due to the reactions of hydroxyl radicals formed in water radiolysis. Hydroxyl radical reacts with diuron with a second order rate constant of (5.8 ± 0.3) × 109 mol−1 dm3 s−1. The main reaction is addition to the ring forming hydroxycyclohexadienyl radical. 30 − 50% of hydroxyl radical reactions induce dechlorination. Reactions with the methyl groups or with the α-amino group have low contribution to the transformation. The presence of dissolved oxygen enhances the rate of degradation; one hydroxyl radical on average induces five-electron oxidations. The high oxidation rate is attributed to the reaction of some of the primarily formed organic radicals with dissolved O2 and the subsequent reactions of the peroxy radicals.ConclusionThe presence of dissolved oxygen is highly important to achieve efficient ionizing radiation induced degradation of diuron in dilute aqueous solution.

show abstract

Section: Discussioncontrasting

confidence: 60%

Ionizing radiation induced degradation of diuron in dilute aqueous solution

Kovács

Mile

et al. 2015

Chemistry Central Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…If the reactivity of the organic radical with O 2 was low, E was well below 1. Aminophenoxy type radicals practically does not react with O 2 [10,40].…”

Section: Removal Efficiency Of Amodiaquinementioning

confidence: 97%

“…For p-aminophenol and acetaminophen (also in air saturated solutions) E ¼ 0.55 and 0.4, respectively, were measured [40]. Based on the initial DCOD/dose slope (Figure 7) E was found to be 0.7 for AQ.…”

Section: Removal Efficiency Of Amodiaquinementioning

confidence: 99%

See 1 more Smart Citation

High-energy ionizing radiation-induced degradation of amodiaquine in dilute aqueous solution: radical reactions and kinetics

Kovács

Simon

Balogh

et al. 2020

Free Radical Research

Self Cite

View full text Add to dashboard Cite

The widely used antimalarial drug amodiaquine (AQ) contains a 7-Cl-quinoline unit, a substituted 4-aminophenol part connected through the amino group and a tertiary amine part. The 4-aminophenol unit can be easily oxidized through radical intermediates to iminoquinone. This reaction also takes place in vitro and in vivo enzymatic reactions. The reaction is expected to have an important role in degradation of AQ in surface waters and also during degradation in advanced oxidation processes. In this paper by means of radiation chemical techniques the one-electron oxidation and reduction of AQ were studied using transient kinetics, kinetics of AQ degradation, formation and decay of end-products of radical reactions. The hydroxyl radicals were shown to add both to the quinoline ($ 38%) and aminophenol ($ 50%) parts via formation of hydroxycyclohexadienyl radicals and by H-abstraction or by an electron removal from the tertiary amine part of the molecule ($ 12%). The dihydroxycyclohexadienyl radical formed on the aminophenol part is suggested to transform to aminophenoxy radical. The hydrated electrons can also effectively contribute to AQ degradation. Chemical oxygen demand and total organic carbon content investigations were also made in order to characterize the ionizing radiation-induced oxidation and mineralization. In aerated 0.1 mmol dm À3 solution, at 2.5 kGy absorbed dose AQ and its higher molecular mass degradation products demolished completely. Ionizing irradiation is a capable technique for degradation of AQ under both oxidative and reductive circumstances.

show abstract

“…It is thought that the efficiencies with which organic compounds are decomposed in an AOP depends on the chemical structures of the organic compounds and the AOP conditions. However, it has been reported about decomposition of various organic compounds using AOP, but there have been relatively few studies of the decomposition efficiencies achieved for compounds with different structures under different AOP conditions [19]. Therefore, we have been studied about the effects of AOPs on the decomposition properties of organic compounds with different structures.…”

Section: Introductionmentioning

confidence: 99%

Effects of Advanced Oxidation Processes on the Decomposition Properties of Organic Compounds with Different Molecular Structures in Water

Suzuki¹,

Yamagiwa²,

Araki³

et al. 2016

JWARP

View full text Add to dashboard Cite

Studies to decompose persistent organic pollutants in wastewater from chemical factories by using Advanced Oxidation Processes (AOPs) have recently been performed. Oxidation reactions involving ozone and •OH radicals and cleavage caused by UV are the main decomposition reactions that occur in AOPs using ozone and UV. The mechanisms through which organic compounds are decomposed in AOPs are complicated and difficult to understand because various decomposition reactions occur simultaneously. The Total Organic Carbon (TOC) removal efficiencies achieved in several different AOPs were evaluated in this study. The TOC removal efficiencies were different for organic compounds with different chemical structures. The TOC was more effectively removed when aromatic compounds were treated using the O3-UV-TiO2 process than when using the other AOPs, and the TOC was removed more effectively by the O3-UV process than by the UV-TiO2 process. However, the TOC was removed more effectively when open-chain compounds were treated using the UV-TiO2 process than using the O3-UV process, and the UV-TiO2 and O3-UV-TiO2 processes resulted in similar TOC removal efficiencies. Therefore, it is necessary to use the O3-UV-TiO2 process to decompose aromatic compounds as quickly as possible. On the other hand, the UV-TiO2 process degraded the open-chain compounds most effectively, and the O3-UV-TiO2 process did not need to decompose open-chain compounds. Moreover, the TOC of aromatic compounds was removed more slowly than that of open-chain compounds. The TOC removal efficiency increased with decreasing the number of carbon atoms in the molecule. The TOC removal efficiencies increased in order of the organic compounds containing methyl groups, aldehyde groups and carboxyl groups. The removal of the TOC when organic compounds were treated using the O3-UV-TiO2 process followed pseudo-zero-order kinetics.

show abstract

Degradation of organic molecules in advanced oxidation processes: Relation between chemical structure and degradability

Cited by 33 publications

References 25 publications

Ionizing radiation induced degradation of diuron in dilute aqueous solution

Ionizing radiation induced degradation of diuron in dilute aqueous solution

High-energy ionizing radiation-induced degradation of amodiaquine in dilute aqueous solution: radical reactions and kinetics

Effects of Advanced Oxidation Processes on the Decomposition Properties of Organic Compounds with Different Molecular Structures in Water

Contact Info

Product

Resources

About