Thermodynamic Analysis on the Mineralization of Trace Organic Contaminants with Oxidants in Advanced Oxidation Processes

Abstract Advanced oxidation processes for the removal and destruction of hazardous organic chemicals in water and wastewater is a research area of increasing interest. Advanced oxidation processes generally consider the hydroxyl radical, OH-, the major reactive transient species. A novel process under development, utilizing high energy electrons, extends this concept to include the simultaneous formation of approximately equal concentrations of oxidizing and reducing species. Irradiation of aqueous solutions results in the formation of the aqueous electron, e−aq, hydrogen atoms, H-, and OH-. These reactive transient species initiate chemical reactions capable of destroying organic compounds in aqueous solution. This paper presents data on the removal of six common organic contaminants that have been studied at the Electron Beam Research Facility. The removal and the factors affecting removal were determined. This study focuses on halogenated ethenes, benzene and substituted benzenes. Removal is described in waters of different quality, including potable water, and raw and secondary wastewater. Removal efficiencies ranged from 85 to >99% and varied with water quality, solute concentration, dose and compound.

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Figures-of-Merit for the Technical Development and Application of Advanced Oxidation Processes

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-1996-0104 ◽

1996 ◽

Vol 1 (1) ◽

Cited By ~ 13

Author(s):

James R. Bolton ◽

Keith G. Bircher ◽

William Tumas ◽

Chadwick A. Tolman

Keyword(s):

Organic Contaminants ◽

Advanced Oxidation Processes ◽

Waste Treatment ◽

Advanced Oxidation ◽

Electrical Energy ◽

Polluted Water ◽

Oxidation Processes ◽

Figures Of Merit ◽

Wide Range ◽

Order Of Magnitude

AbstractAdvanced oxidation processes (AOPs), which involve the in-situ generation of highly potent chemical oxidants such as the hydroxyl radical (•OH), have recently emerged as an important class of technologies for accelerating the oxidation and hence destruction of a wide range of organic contaminants in polluted water and air. We propose generally applicable standard figures-of-merit for comparing these waste treatment technologies. These figures-of-merit are based on electrical energy consumption within two phenomenological kinetic order regimes: one for high contaminant concentrations (electrical energy per mass, EE/M) and one for low concentrations (electrical energy per order of magnitude per m

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Perovskites as Catalysts in Advanced Oxidation Processes for Wastewater Treatment

Catalysts ◽

10.3390/catal9030230 ◽

2019 ◽

Vol 9 (3) ◽

pp. 230 ◽

Cited By ~ 10

Author(s):

María Rojas-Cervantes ◽

Eva Castillejos

Keyword(s):

Organic Contaminants ◽

Photocatalytic Oxidation ◽

Advanced Oxidation Processes ◽

High Mobility ◽

Advanced Oxidation ◽

Oxidation States ◽

Effluent Water ◽

Oxidation Processes ◽

Reactive Radicals ◽

Perovskite Type

Advanced oxidation processes (AOPs), based on the formation of highly reactive radicals are able to degrade many organic contaminants present in effluent water. In the heterogeneous AOPS the presence of a solid which acts as catalyst in combination with other systems (O3, H2O2, light) is required. Among the different materials that can catalyse these processes, perovskites are found to be very promising, because they are highly stable and exhibit a high mobility of network oxygen with the possibility of forming vacancies and to stabilize unusual oxidation states of metals. In this review, we show the fundaments of different kinds of AOPs and the application of perovskite type oxides in them, classified attending to the oxidant used, ozone, H2O2 or peroxymonosulfate, alone or in combination with other systems. The photocatalytic oxidation, consisting in the activation of the perovskite by irradiation with ultraviolet or visible light is also revised.

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Kinetic Study on Degradation of Micro-organics by Different UV-based advanced oxidation processes in EfOM Matrix

10.21203/rs.3.rs-719769/v1 ◽

2021 ◽

Author(s):

Donghai Yuan ◽

Guangyu Liu ◽

Fei Qi ◽

Jinggang Wang ◽

Yingying Kou ◽

...

Keyword(s):

Organic Matter ◽

Organic Contaminants ◽

Advanced Oxidation Processes ◽

Degradation Kinetics ◽

Advanced Oxidation ◽

Negative Effects ◽

Effluent Organic Matter ◽

Chlorobenzoic Acid ◽

Oxidation Processes ◽

Competitive Kinetics

Abstract Effluent Organic Matter (EfOM) contains a large number of substances that are harmful to both the environment and human health. To avoid the negative effects of organic matter in EfOM, advanced treatment of organic matter is an urgent task. Four typical oxidants (H2O2, PS, PMS, NaClO) and UV-combined treatments were used to treat micro-contaminants in the presence or absence of effluent organic matter (EfOM), because the active radical species produced in these UV-AOPs are highly reactive with organic contaminants. However, the removal efficiency of trace contaminants was greatly affected by the presence of EfOM. The degradation kinetics of two representative micro-contaminants (benzoic acid (BA) and para-chlorobenzoic acid(p-CBA)) was significantly reduced in the presence of EfOM, compared to the degradation kinetics in its absence. Using the method of competitive kinetics, with BA, p-CBA and 1,4-dimethoxybenzene (DMOB) as probes, the radicals (HO·, SO4-·, ClO·) proved to be the key to reaction species in advanced oxidation processes. UV irradiation on EfOM was not primarily responsible for the degradation of micro-contaminants. The second-order rate constants of the EfOM with radicals were determined to be (5.027±0.643)×102(SO4-·), (3.192±0.153)×104 (HO·) and 1.35×106 (ClO·) (mg-C/L)-1·s-1. In addition, this study evaluated the production of three radicals based on the concept of Rct, which can better analyze its reaction mechanism.

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Trace Organic Compound Removal from Wastewater Reverse-Osmosis Concentrate by Advanced Oxidation Processes with UV/O3/H2O2

Materials ◽

10.3390/ma13122785 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2785

Author(s):

Aviv Kaplan ◽

Hadas Mamane ◽

Yaal Lester ◽

Dror Avisar

Keyword(s):

Reverse Osmosis ◽

Metal Ion ◽

Advanced Oxidation Processes ◽

Advanced Oxidation ◽

Treated Wastewater ◽

Nutrient Concentrations ◽

Secondary Effluent ◽

Radical Oxidation ◽

Oxidation Processes ◽

Trace Organic

Advanced technologies, such as reverse osmosis (RO), allow the reuse of treated wastewater for direct or indirect potable use. However, even highly efficient RO systems produce ~10–15% highly contaminated concentrate as a byproduct. This wastewater RO concentrate (WWROC) is very rich in metal ions, nutrients, and hard-to-degrade trace organic compounds (TOrCs), such as pharmaceuticals, plasticizers, flame retardants, and detergents, which must be treated before disposal. WWROC could be up to 10 times more concentrated than secondary effluent. We examined the efficiency of several advanced oxidation processes (AOPs) on TOrC removal from a two-stage WWROC matrix in a pilot wastewater-treatment facility. WWROC ozonation or UV irradiation, with H2O2 addition, demonstrated efficient removal of TOrCs, varying between 21% and over 99% degradation, and indicating that radical oxidation (by HO·) is the dominant mechanism. However, AOPs are not sufficient to fully treat the WWROC, and thus, additional procedures are required to decrease metal ion and nutrient concentrations. Further biological treatment post-AOP is also highly important, to eliminate the degradable organic molecules obtained from the AOP.

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