Interaction of Ozone and Hydrogen Peroxide in Water Implications For
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Ozonedisinfection.Pdf
ETI - Environmental Technology Initiative Project funded by the U.S. Environmental Protection Agency under Assistance Agreement No. CX824652 What is disinfection? Human exposure to wastewater discharged into the environment has increased in the last 15 to 20 years with the rise in population and the greater demand for water resources for recreation and other purposes. Disinfection of wastewater is done to prevent infectious diseases from being spread and to ensure that water is safe for human contact and the environment. There is no perfect disinfectant. However, there are certain characteristics to look for when choosing the most suitable disinfectant: • Ability to penetrate and destroy infectious agents under normal operating conditions; • Lack of characteristics that could be harmful to people and the environment; • Safe and easy handling, shipping, and storage; • Absence of toxic residuals, such as cancer-causing compounds, after disinfection; and • Affordable capital and operation and maintenance (O&M) costs. What is ozone disinfection? One common method of disinfecting wastewater is ozonation (also known as ozone disinfection). Ozone is an unstable gas that can destroy bacteria and viruses. It is formed when oxygen molecules (O2) collide with oxygen atoms to produce ozone (O3). Ozone is generated by an electrical discharge through dry air or pure oxygen and is generated onsite because it decomposes to elemental oxygen in a short amount of time. After generation, ozone is fed into a down-flow contact chamber containing the wastewater to be disinfected. From the bottom of the contact chamber, ozone is diffused into fine bubbles that mix with the downward flowing wastewater. See Figure 1 on page 2 for a schematic of the ozonation process. -
The Decomposition Kinetics of Peracetic Acid and Hydrogen Peroxide in Municipal Wastewaters
Disinfection Forum No 10, October 2015 The Decomposition Kinetics of Peracetic Acid and Hydrogen Peroxide in Municipal Wastewaters INTRODUCTION Efficient control of microbial populations in municipal wastewater using peracetic acid (PAA) requires an understanding of the PAA decomposition kinetics. This knowledge is critical to ensure the proper dosing of PAA needed to achieve an adequate concentration within the contact time of the disinfection chamber. In addition, the impact of PAA on the environment, post-discharge into the receiving water body, also is dependent upon the longevity of the PAA in the environment, before decomposing to acetic acid, oxygen and water. As a result, the decomposition kinetics of PAA may have a significant impact on aquatic and environmental toxicity. PAA is not manufactured as a pure compound. The solution exists as an equilibrium mixture of PAA, hydrogen peroxide, acetic acid, and water: ↔ + + Acetic Acid Hydrogen Peroxide Peracetic Acid Water PeroxyChem’s VigorOx® WWT II Wastewater Disinfection Technology contains 15% peracetic acid by weight and 23% hydrogen peroxide as delivered. Although hydrogen peroxide is present in the formulation, peracetic acid is considered to be the active component for disinfection1 in wastewater. There have been several published studies investigating the decomposition kinetics of PAA in different water matrices, including municipal wastewater2-7. Yuan7 states that PAA may be consumed in the following three competitive reactions: 1. Spontaneous decomposition 2 CH3CO3H à 2 CH3CO2H + O2 Eq (1) 2. Hydrolysis CH3CO3H + H2O à CH3CO2H + H2O2 Eq (2) 3. Transition metal catalyzed decomposition + CH3CO3H + M à CH3CO2H + O2 + other products Eq (3) At neutral pH’s, both peracetic acid and hydrogen peroxide can be rapidly consumed by these reactions7 (hydrogen peroxide will decompose to water and oxygen via 2H2O2 à 2H2O + O2). -
University of Groningen Discovery of a Eugenol Oxidase From
University of Groningen Discovery of a eugenol oxidase from Rhodococcus sp strain RHA1 Jin, J.F.; Mazon, H.; van den Heuvel, R.H.H.; Janssen, D.B.; Fraaije, M.W. Published in: Febs Journal DOI: 10.1111/j.1742-4658.2007.05767.x IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 2007 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Jin, J. F., Mazon, H., van den Heuvel, R. H. H., Janssen, D. B., & Fraaije, M. W. (2007). Discovery of a eugenol oxidase from Rhodococcus sp strain RHA1. Febs Journal, 274(9), 2311 - 2321. https://doi.org/10.1111/j.1742-4658.2007.05767.x Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 23-09-2021 Discovery of a eugenol oxidase from Rhodococcus sp. -
Algorithmic Analysis of Chemical Dynamics of the Autoignition of NH3–H2O2/Air Mixtures
energies Article Algorithmic Analysis of Chemical Dynamics of the Autoignition of NH3–H2O2/Air Mixtures Ahmed T. Khalil 1,2, Dimitris M. Manias 3, Efstathios-Al. Tingas 4, Dimitrios C. Kyritsis 1,2,* and Dimitris A. Goussis 1,2 1 Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, UAE; [email protected] (A.T.K.); [email protected] (D.A.G.) 2 Research and Innovation Center on CO2 and H2 (RICH), Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, UAE 3 Department of Mechanics, School of Applied Mathematics and Physical Sciences, National Technical University of Athens, 157 73 Athens, Greece; [email protected] 4 Perth College, University of the Highlands and Islands, (UHI), Perth PH1 2NX, UK; [email protected] * Correspondence: [email protected] Received: 8 September 2019; Accepted: 7 October 2019; Published: 21 November 2019 Abstract: The dynamics of a homogeneous adiabatic autoignition of an ammonia/air mixture at constant volume was studied, using the algorithmic tools of Computational Singular Perturbation. Since ammonia combustion is characterized by both unrealistically long ignition delays and elevated NOx emissions, the time frame of action of the modes that are responsible for ignition was analyzed by calculating the developing time scales throughout the process and by studying their possible relation to NOx emissions. The reactions that support or oppose the explosive time scale were identified, along with the variables that are related the most to the dynamics that drive the system to an explosion. -
Ethanol Purification with Ozonation, Activated Carbon Adsorption, and Gas Stripping Shinnosuke Onuki Iowa State University
Agricultural and Biosystems Engineering Agricultural and Biosystems Engineering Publications 9-4-2015 Ethanol purification with ozonation, activated carbon adsorption, and gas stripping Shinnosuke Onuki Iowa State University Jacek A. Koziel Iowa State University, [email protected] William S. Jenks Iowa State University, [email protected] Lingshuang Cai Iowa State University Somchai Rice Iowa State University SeFoe nelloxtw pa thige fors aaddndition addal aitutionhorsal works at: https://lib.dr.iastate.edu/abe_eng_pubs Part of the Agriculture Commons, Bioresource and Agricultural Engineering Commons, and the Organic Chemistry Commons The ompc lete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ abe_eng_pubs/909. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Agricultural and Biosystems Engineering at Iowa State University Digital Repository. It has been accepted for inclusion in Agricultural and Biosystems Engineering Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Ethanol purification with ozonation, activated carbon adsorption, and gas stripping Abstract Fermentation of sugar to produce ethanol also produces volatile byproducts. This study was aimed at purifying corn-based ethanol for industrial and pharmaceutical use. The er search was on treatment for 10 impurities removal after distillation. The the anol headspace was sampled with solid-phase microextraction and analyzed with gas chromatography–mass spectrometry. A 40 mg/L ozone treatment resulted in >56% and >36% removal of styrene and 2-pentylfuran, respectively, without significant generation of byproducts. -
Publication No. 17: Ozone Treatment of Private Drinking Water Systems
PRIVATE DRINKING WATER IN CONNECTICUT Publication Date: April 2009 Publication No. 17: Ozone Treatment of Private Drinking Water Systems Effective Against: Pathogenic (disease-causing) organisms including bacteria and viruses, phenols (aromatic organic compounds), some color, taste and odor problems, iron, manganese, and turbidity. Not Effective Against: Large cysts and some other large organisms resulting from possible or probable sewage contamination, inorganic chemicals, and heavy metals. How Ozone (O3) Treatment Works Ozone is a chemical form of pure oxygen. Like chlorine, ozone is a strong oxidizing agent and is used in much the same way to kill disease-causing bacteria and viruses. It is effective against most amoebic cysts, and destroys bacteria and some aromatic organic compounds (such as phenols). Ozone may not kill large cysts and some other large organisms, so these should be eliminated by filtration or other procedures prior to ozone treatment. Ozone is effective in eliminating or controlling color, taste, and odor problems. It also oxidizes iron and manganese. Ozone treatment units are installed as point-of-use treatment systems. Raw water enters one opening and treated water emerges from another. Inside the treatment unit, ozone is produced by an electrical corona discharge or ultraviolet irradiation of dry air or oxygen. The ozone is mixed with the water whenever the water pump is running. Ozone generation units require a system to clean and remove the humidity from the air. For proper disinfection the water to be treated must have negligible color and turbidity levels. The system requires routine maintenance and an ozone treatment system can be very energy consumptive. -
Ozone: Good up High, Bad Nearby
actions you can take High-Altitude “Good” Ozone Ground-Level “Bad” Ozone •Protect yourself against sunburn. When the UV Index is •Check the air quality forecast in your area. At times when the Air “high” or “very high”: Limit outdoor activities between 10 Quality Index (AQI) is forecast to be unhealthy, limit physical exertion am and 4 pm, when the sun is most intense. Twenty minutes outdoors. In many places, ozone peaks in mid-afternoon to early before going outside, liberally apply a broad-spectrum evening. Change the time of day of strenuous outdoor activity to avoid sunscreen with a Sun Protection Factor (SPF) of at least 15. these hours, or reduce the intensity of the activity. For AQI forecasts, Reapply every two hours or after swimming or sweating. For check your local media reports or visit: www.epa.gov/airnow UV Index forecasts, check local media reports or visit: www.epa.gov/sunwise/uvindex.html •Help your local electric utilities reduce ozone air pollution by conserving energy at home and the office. Consider setting your •Use approved refrigerants in air conditioning and thermostat a little higher in the summer. Participate in your local refrigeration equipment. Make sure technicians that work on utilities’ load-sharing and energy conservation programs. your car or home air conditioners or refrigerator are certified to recover the refrigerant. Repair leaky air conditioning units •Reduce air pollution from cars, trucks, gas-powered lawn and garden before refilling them. equipment, boats and other engines by keeping equipment properly tuned and maintained. During the summer, fill your gas tank during the cooler evening hours and be careful not to spill gasoline. -
Toxicological Profile for Acetone Draft for Public Comment
ACETONE 1 Toxicological Profile for Acetone Draft for Public Comment July 2021 ***DRAFT FOR PUBLIC COMMENT*** ACETONE ii DISCLAIMER Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services. This information is distributed solely for the purpose of pre dissemination public comment under applicable information quality guidelines. It has not been formally disseminated by the Agency for Toxic Substances and Disease Registry. It does not represent and should not be construed to represent any agency determination or policy. ***DRAFT FOR PUBLIC COMMENT*** ACETONE iii FOREWORD This toxicological profile is prepared in accordance with guidelines developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The original guidelines were published in the Federal Register on April 17, 1987. Each profile will be revised and republished as necessary. The ATSDR toxicological profile succinctly characterizes the toxicologic and adverse health effects information for these toxic substances described therein. Each peer-reviewed profile identifies and reviews the key literature that describes a substance's toxicologic properties. Other pertinent literature is also presented, but is described in less detail than the key studies. The profile is not intended to be an exhaustive document; however, more comprehensive sources of specialty information are referenced. The focus of the profiles is on health and toxicologic information; therefore, each toxicological profile begins with a relevance to public health discussion which would allow a public health professional to make a real-time determination of whether the presence of a particular substance in the environment poses a potential threat to human health. -
Hydrogen Peroxide Cas #7722-84-1
HYDROGEN PEROXIDE CAS #7722-84-1 Division of Toxicology ToxFAQsTM April 2002 This fact sheet answers the most frequently asked health questions (FAQs) about hydrogen peroxicde. For more information, call the ATSDR Information Center at 1-888-422-8737. This fact sheet is one in a series of summaries about hazardous substances and their health effects. It is important you understand this information because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present. HIGHLIGHTS: Hydrogen peroxide is a manufactured chemical, although small amounts of hydrogen peroxide gas may occur naturally in the air. Low exposure may occur from use at home; higher exposures may occur from industrial use. Exposure to hydrogen peroxide can cause irritation of the eyes, throat, respiratory airway, and skin. Drinking concentrated liquid can cause mild to severe gastrointestinal effects. This substance has been found in at least 18 of the 1,585 National Priorities List sites identified by the Environmental Protection Agency (EPA). What is hydrogen peroxide? ‘ If released to soil, hydrogen peroxide will be broken down Hydrogen peroxide is a colorless liquid at room temperature by reacting with other compounds. with a bitter taste. Small amounts of gaseous hydrogen peroxide occur naturally in the air. Hydrogen peroxide is ‘ Hydrogen peroxide does not accumulate in the food chain. unstable, decomposing readily to oxygen and water with release of heat. Although nonflammable, it is a powerful How might I be exposed to hydrogen peroxide? oxidizing agent that can cause spontaneous combustion when it comes in contact with organic material. -
Production of Hydrogen Peroxide from Carbon Monoxide, Water and Oxygen Over Alumina-Supported Ni Catalysts
_______________________________________________________________________________www.paper.edu.cn Journal of Molecular Catalysis A: Chemical 210 (2004) 157–163 Production of hydrogen peroxide from carbon monoxide, water and oxygen over alumina-supported Ni catalysts Zhong-Long Ma, Rong-Li Jia, Chang-Jun Liu∗ Key Laboratory of Green Synthesis and Transformation of Ministry of Education, School of Chemical Engineering and Technologies, Tianjin University, Tianjin 300072, PR China Received 23 April 2003; accepted 11 September 2003 Abstract Novel amorphous Ni–B catalysts supported on alumina have been developed for the production of hydrogen peroxide from carbon monoxide, water and oxygen. The experimental investigation confirmed that the promoter/Ni ratio and the preparation conditions have a significant effect on the activity and lifetime of the catalyst. Among all the catalysts tested, the Ni–La–B/␥-Al2O3 catalyst with a 1:15 atomic ratio of La/Ni, dried at 120 ◦C, shows the best activity and lifetime for the production of hydrogen peroxide. The deactivation of the alumina-supported Ni–B amorphous catalyst was also studied. According to the characterizations of the fresh and used catalysts by SEM, XRD and XPS, no sintering of the active component and crystallization of the amorphous species were observed. However, it is water poisoning that leads to the deactivation of the catalyst. The catalyst characterization demonstrated that the active component had changed (i.e., amorphous NiO to amorphous Ni(OH)2) and then salt was formed in the reaction conditions. Water promoted the deactivation because the surface transformation of the active Ni species was accelerated by forming Ni(OH)2 in the presence of water. -
Focus on Sulfur Dioxide (SO2)
The information presented here reflects EPA's modeling of the Clear Skies Act of 2002. The Agency is in the process of updating this information to reflect modifications included in the Clear Skies Act of 2003. The revised information will be posted on the Agency's Clear Skies Web site (www.epa.gov/clearskies) as soon as possible. Overview of the Human Health and Environmental Effects of Power Generation: Focus on Sulfur Dioxide (SO2), Nitrogen Oxides (NOX) and Mercury (Hg) June 2002 Contents The Clear Skies Initiative is intended to reduce the health and environmental impacts of power generation. This document briefly summarizes the health and environmental effects of power generation, specifically those associated with sulfur dioxide (SO2), nitrogen oxides (NOX), and mercury (Hg). This document does not address the specific impacts of the Clear Skies Initiative. • Overview -- Emissions and transport • Fine Particles • Ozone (Smog) • Visibility • Acid Rain • Nitrogen Deposition • Mercury Photo Credits: 1: USDA; EPA; EPA; VTWeb.com 2: NADP 6: EPA 7: ?? 10: EPA 2 Electric Power Generation: Major Source of Emissions 2000 Sulfur Dioxide 2000 Nitrogen Oxides 1999 Mercury Fuel Combustion- Industrial Processing electric utilities Transportation Other stationary combustion * Miscellaneous * Other stationary combustion includes residential and commercial sources. • Power generation continues to be an important source of these major pollutants. • Power generation contributes 63% of SO2, 22% of NOX, and 37% of man-made mercury to the environment. 3 Overview of SO2, NOX, and Mercury Emissions, Transport, and Transformation • When emitted into the atmosphere, sulfur dioxide, nitrogen oxides, and mercury undergo chemical reactions to form compounds that can travel long distances. -
Hydrogen Peroxide Oxidation of Aromatic Hydrocarbons by Immobilized Iron(III)
Journal of Molecular Catalysis A: Chemical 217 (2004) 161–164 Hydrogen peroxide oxidation of aromatic hydrocarbons by immobilized iron(III) Hassan Hosseini Monfared∗, Zahra Amouei Department of Chemistry, School of Sciences, Zanjan University, Zanjan 45195-313, Iran Received 30 October 2003; received in revised form 16 March 2004; accepted 16 March 2004 Available online 27 April 2004 Abstract Supported iron(III) ions on neutral ␥-alumina are an efficient catalyst for the oxidation of aromatic hydrocarbons with hydrogen peroxide in acetonitrile at 60 ◦C. The catalyst is active in the low temperatue liquid phase oxidation of benzene, toluene, chlorobenzene, p-xylene, mesitylene, benzaldehyde with hydrogen peroxide. Conversions of 31–88% with respect to starting substrate were obtained within 6 h. Oxidation on both the side chain and the aromatic ring of hydrocarbons occurred. © 2004 Elsevier B.V. All rights reserved. Keywords: Aromatic hydrocarbons; Hydrogen peroxide; Heterogeneous catalyst; Oxidation 1. Introduction ions on silica [4] or alumina [5], considerably retards the non-productive decomposition of H2O2. Here, we report that The selective catalytic oxidation of organic molecules supported iron ions on ␥-alumina show remarkable catalytic continues to be a very important method for the prepara- properties in activation of H2O2 for aromatic hydrocarbons tion of primary and specialty chemicals in the chemical oxidation. industry worldwide. Catalytic oxidation reactions using metal complexes are valuable for facilitation the devel- opment