2 edition of Oxidation of refractory organic materials by ozone and ultraviolet light found in the catalog.
Oxidation of refractory organic materials by ozone and ultraviolet light
Cecil G. Hewes
|Statement||prepared by Cecil G. Hewes ...[et al.]|
|The Physical Object|
|Pagination||58 p. (iv, 110 p.) :|
|Number of Pages||110|
Example of ion exchange oxidation of ozone and iron: Fe+2 + O3 = FE+3 + O3- Example of oxygen atom exchange oxidation of ozone and iron: 2Fe2+ + O3 + H2 O → 2Fe3+ + O2 + 2OH- Both reactions can occur with organic and inorganic compounds. This is just one simple example of ozone oxidation . UV oxidation is a destruction process that oxidizes organic and explosive constituents in wastewater by the addition of strong oxidizers and irradiation with UV light. Oxidation of target contaminants is caused by direct reaction with the oxidizers, UV photolysis, and through the synergistic action of UV light, in combination with ozone (O 3.
Book References: UV Ozone Cleaner. Microdevices in Biology and Medicine Yaakov Nahmias, Sangeeta Bhatia - - isbn= An alternative method using a commercial UV-ozone (UV O3) source can be used with equal effect as outlined below. Device bonding (with UV O3 surface treatment) 1. Atrazine, propazine, and terbuthylazine are chlorotriazine herbicides that have been frequently used in agriculture and thus are potential drinking water contaminants. Hydroxyl radicals produced by advanced oxidation processes can degrade these persistent compounds. These herbicides are also very reactive with sulfate radicals (– × M–1 s–1).
Aluminium oxide (IUPAC name) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula Al 2 O is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) is commonly called alumina and may also be called aloxide, aloxite, or alundum depending on particular forms or applications. Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency of approximately 30 PHz) to nm ( THz), shorter than that of visible light but longer than radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the is also produced by electric arcs and specialized.
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Advanced oxidation processes (AOPs) are alternative techniques of destruction of harmful organic pollutants from contaminated water and air. These processes involve UV-based processes (UV/O 3 /H 2 O 2), chemical oxidation processes (O 3 /H 2 O 2), Fenton and photo-Fenton processes (Fe 2+ /H 2 O 2 /UV), photocatalytic redox processes (semiconductor/UV), supercritical water oxidation, sonolysis.
Advanced oxidation processes (AOP) combine ozone (O3), ultraviolet, hydrogen peroxide and/or catalyst to offer a powerful water treatment solution for the reduction (removal) of residual organic compounds as measured by COD, BOD or TOC. All AOP are designed to produce hydroxyl radicals.
ultra-violet enhanced oxidation such as UV/ozone, UV/hydrogen peroxide, UV/air wet air oxidation and catalytic wet air oxidation (where air is used as the oxidant) Advanced oxidation processes are particularly appropriate for effluents containing refractory, toxic or non-biodegradable materials.
(). Degradation of Refractory Organic Pollutants by Catalytic Ozonation—Activated Carbon and Mn-Loaded Activated Carbon as Catalysts. Ozone: Science & Cited by: Hydrogen peroxide (H2O2), Ozonation, Ultra-violet (UV) radiation, H2O2/UV process and Fenton’s reaction are extensively used for the removal of refractory organic compounds thus reducing Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), phenolic compounds, dyes etc.
to great by: 2. Achieving ozone destruction with UV electromagnetic radiation depends on the wavelength of the UV light source and the quantity of energy transmitted (Rodriguez and Gagnon,Hunter et al., ). Ozone residuals are destroyed at UV light wavelengths ranging from to nm.
Ironically, UV wavelengths of nm can be used to generate ozone. The oxidation potential of the hydroxyl radical (E 0 = V) is much larger than that of the ozone (E 0 = V), therefore, the combination of ozone and UV radiation and / or H 2 O 2 produce hydroxyl, superoxide and perhydroxyl radicals, generating processes which synergistically accelerate the removal of organic material .
Ozone Reaction with Various Compounds. Many organic and inorganic compounds react with ozone. These reactions can vary greatly depending upon the state of ozone (gaseous or aqueous), and the other chemicals involved in the reaction.
Below is an outline of basic chemical reactions between ozone and certain compounds. This secondary oxidant can cause the oxidation of most organic compounds until they are fully mineralized as carbon dioxide and water.
The hydroxyl radical has a much higher oxidation potential than ozone or hydrogen peroxide and usually reacts at least one million times faster, thus leading to a smaller contact time and footprint. The staged ozone reactor with UV light and/or heat is extremely effective in treating refractory compounds in wastewater, as demonstrated in the pilot scale runs with ferricyanide complex.
In such cases, based on its high oxidation potential, ozone is widely utilized in tertiary water treatment for the degradation of refractory and toxic organic pollutants (Peña et al., Description of the UV/O₃ oxidation of trichloroethylene Peyton et al.
First comprehensive reviews of advanced oxidation processes involving ozone, hydrogen peroxide, and ultraviolet light.
Introduction of the term advanced oxidation technologies (AOTs). Glaze et. Textile dyes are one of the most significant organic pollutants that are responsible for numerous environmental problems. This study was performed to determine the process efficiency of the greener silver nanoparticles/hydrogen peroxide/ozone combination to degrade, common dye, and reactive blue The removal efficiency for reactive blue 19 and chemical oxygen demand (COD) was.
Advanced oxidation processes (AOPs) were first proposed in the s for drinking water treatment and later were widely studied for treatment of different wastewaters. During the AOP treatment of wastewater, hydroxyl radicals (OH) or sulfate radicals (SO4 −) are generated in sufficient quantity to remove refractory organic matters, traceable organic contaminants, or certain inorganic.
The combination of ozonation with irradiation by ultraviolet light has been reported to overcome the latter difficulty by degrading even refractory organic compounds completely to carbon dioxide and water- In addition, the ozone/UV process has been reported to be considerably faster than ozone alone for the destruction of almost all organic.
OH radicals react and destroy any organic and inorganic contaminants in water and wastewater. The most popular AOPs are based on the combination of ozone or UV light with different chemicals, such as UV/H2O2, ozone/H2O2 and photoFenton (UV/H2O2/Fe). Advanced Oxidation Process (AOP) Ozone combined with: Hydrogen Peroxide H 2 O 2 decomposes in the presence of O 3 into Hydroxyl Radicals – highly reactive free radicals Ultraviolet UV provides energy to break chemical bonds, leaving fragments that are more susceptible to oxidation.
Converts H 2 O 2 to hydroxyl radicals. Converts O 3 to O 2. such as iron salts, and UV light can activate H2O2 to form hydroxyl radicals which are strong oxidants.
Oxidation processes utilizing activation of H2O2 by iron salts, termed Fenton's reagent, are discussed in the following section. Oxidation processes utilizing UV and/or ozone as. Ozone. Ozone is a powerful oxidizing agent with a high reduction potential (V) that can react with many organic substrates [18,19].
Using ozone, the oxidation of the organic matrix can occur via either direct or indirect routes [20,21]. In the direct oxidation route, ozone molecules can react directly with other organic or inorganic.
Recent techniques that achieve more complete oxidation have involved (1) combinations of ultraviolet radiation and oxidants (ozone, hydrogen peroxide) in homogeneous systems or (2) heterogeneous photocatalytic systems that combine near ultraviolet radiation ( to nm range) with light-activated oxidation catalysts such as titanium dioxide.
Advanced oxidation processes are defined as those which involve the generation of hydroxyl radicals in sufficient quantity to affect water purification. The theoretical and (practical yield of OH from O 3 at high pH, 0 3 /H 2 0 2, O 3 /UV and H 2 O 2 /UV systems is reviewed. The ozone decomposition quantum yield (Φ) in millimolar and higher-concentration aqueous tertiary butanol solution is ± (observed over a wavelength range from to nm) and rises toward lower tertiary butanol concentrations (Φ ≈ at M at pH 2) on account of the onset of the well-known •OH-radical-induced chain reaction.
The destruction of the organic is initiated.Advanced oxidation using ozone (O 3), ozone with hydrogen peroxide (O 3 /H 2 O 2), ozone with ultraviolet light (O 3 /UV), hydrogen peroxide with ultraviolet light (H 2 O 2 /UV), Fenton process (H 2 O 2 /Fe 2+), and photo-Fenton process (H 2 O 2 /Fe 2+ /UV) for the treatment of old or biologically treated landfill leachate has been intensively.