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Impact of Growth Conditions, pH, and Suspension Time on Toxin Release from Microcystis Aeruginosa Upon Exposure to Potassium PermanganateRoland, David January 2018 (has links)
No description available.
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Optimization and Analysis of a Slow-Release Permanganate Gel for TCE Plume Treatment in GroundwaterOgundare, Ojo Oluwaseun 02 June 2021 (has links)
No description available.
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Geochemical Impacts From Permanganate Oxidation Based on Field Scale Assessments.Moore, Kelly Ann 13 December 2008 (has links) (PDF)
In situ chemical oxidation (ISCO) using permanganate is a technology for treatment of organic hazardous wastes. This research is a review of 30 permanganate (MnO4-) ISCO sites to determine whether there are long term impacts on groundwater quality due to the introduction of the oxidant into the subsurface. A second objective is to determine if manganese concentration can be predicted by trends in specific pre and postoxidation monitored parameters (i.e., pH and oxidation reduction potential (ORP)). The final objective is to identify the effects of site and design conditions on groundwater conditions postoxidation. Results indicate that (1) there are limited long term groundwater impacts due to oxidant introduction (i.e., water quality indicators begin to approach preoxidation levels by 2 years postoxidation), (2) manganese concentrations can be predicted and (3) site and design conditions have pronounced short term impacts on geochemical parameters (i.e., especially site media type, mass of oxidant injected, and initial ORP).
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Study of the Formation and Control of Disinfection By-Products Originating from a Surface Water Supply on the Volcanic Island of GuamLaBerge, Erica 01 January 2014 (has links)
Three oxidants have been evaluated for use as alternative chemical pretreatments for Fena Lake, a surface water that supplies the U.S. Navy's Public Water System (PWS) on the volcanic island of Guam. The study consisted of two investigative components. The first and primary component included a bench-scale evaluation to study the effects of different pre-oxidant chemicals on the formation of chlorinated disinfection by-products (DBPs). The second and ancillary component included a series of water treatment and distribution system management studies that analyzed DBP formation within the treatment plant and water distribution system. The goal of this research was to reduce total trihalomethane (TTHM) and the five haloacetic acid (HAA5) formations in the PWS. In the primary component of the research, raw surface water from Fena Lake was collected by U.S. Navy personnel and shipped to University of Central Florida (UCF) laboratories for experimentation. Bench-scale tests that simulated the coagulation, flocculation, sedimentation and filtration (CSF) that comprises the Navy Water Treatment Plant (NWTP) were used to evaluate the use of two alternative pre-oxidants, potassium permanganate (KMnO4) and chlorine dioxide (ClO2) in lieu of gaseous chlorine (Cl2). The research assessed DBP formation by comparing several pretreatment scenarios, namely: (1) no pretreatment, (2) chlorine pretreatment, and (3) alternative oxidant pretreatment. KMnO4 pretreatment resulted in the lowest percent reduction of TTHMs and HAA5 relative to chlorine pretreatment, at 5.7% and 22.7%, respectively; however, this amount was still a reduction from the results demonstrated for the chlorine pretreatment condition. Without using a pre-oxidant, TTHM and HAA5 formation were reduced by 22.8% and 37.3%, respectively, relative to chlorine pretreatment. Chlorine dioxide demonstrated the greatest TTHM and HAA5 reduction relative to chlorine pretreatment at 34.4% and 53.3%, respectively. The second component of research consisted of a series of studies that evaluated distribution system operations and management alternatives to identify opportunities that could achieve DBP reduction within the PWS. Three concerns that were addressed were the NWTP's compliance with the U.S. Environmental Protection Agency's (USEPA's) Stage 2 Disinfectants/Disinfection By-Products (D/DBP) Rule, variable hydraulic detention times within a small subdivision in the distribution system, and severe weather. It was determined that: (1) A decision based on in-plant studies to cease prechlorination at the NWTP resulted in a decrease in TTHMs and HAA5s throughout the distribution system by 62% and 75%, respectively; (2) A fluoride tracer study led to the discovery of a valved pipeline responsible for elevated DBPs because of excessive water age that when exercised and managed resolved intermittent DBP spikes in the PWS; and (3) when the NWTP's ballasted floc clarifier (BFC) was operated in-series prior to the conventional CSF process during severe weather conditions the TTHM and HAA5 were below 39 ug/L and 29 ug/L, respectively, proving BFC in-series is a practical option for the plant during severe weather.
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Novel Remediation Schemes for Groundwater and Urban RunoffOlson, Pamela Renee 26 July 2011 (has links)
No description available.
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Design of new activated carbon based adsorbents for improved desulfurization of heavy gas oil: Experiments and kinetic modelingNawaf, A.T., Jarullah, A.T., Hameed, S.A., Mujtaba, Iqbal M. 31 March 2022 (has links)
Yes / In this work, adsorption desulfurization is considered for making cleaner fuel. New efficient adsorbents have been designed by using two active metal oxides mainly potassium permanganate (KMnO4) and potassium phosphate (KPO4·3H2O) on Activated Carbon (AC). Ultrasonic assisted impregnation method (IWI) is used in designing the adsorbents offering high pore volume, pore size, surface chemistry, and high surface area. Use of ultrasonic method increases the dispersion of the active material (groups) on AC leading to increased number of collisions between O-atom on AC-support resulting in high sulfur removal from fuel. KMnO4 on AC shows higher adsorption capacity towards sulfur than KPO4·3H2O at the same operating conditions. New results with respect to sulfur removal has obtained compared with those obtained by previous studies. Finally, the adsorption kinetic parameters of such process are developed. Thomas and Yoon-Nelson models and the experimental data are used for this purpose using linear and non-linear regression analysis. Yoon-Nelson kinetic model fits well with the experiments data better than Thomas kinetic model in the entire adsorption column system.
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An investigation of the oxidative potential of potassium permanganate and chlorine dioxide during the oxidation of reduced manganeseHair, David Hayne 17 November 2012 (has links)
This project determined the thermodynamic potentials for various reactions between reduced manganese (Mn²), manganese oxide (MnO₂(s)), chlorine dioxide (Cl0₂), and potassium permanganate (KMnO₄). Based on these findings, laboratory analyses were performed to determine if these reactions would occur under simulated water treatment plant conditions. In addition, a speciation procedure was developed to quantify the various species of manganese and chlorine dioxide present in a single sample. The reactions and the speciation procedure were evaluated at TOC concentrations ranging from < 1.0 mg/L to 5.0 mg/L and at pH 6.0 and 8.0. The speciation procedure yielded a reliable measure of Mn², insoluble manganese, and Mn⁺⁷; however, the Mn⁺⁷ evaluation could be disrupted by the presence of free chlorine. The determination of Cl0₂ and Cl0₂- concentrations was also possible; however, the C10₂- concentration was subject to error.
The laboratory analyses revealed that Cl0₂ was unable to oxidize either Mn² or MnO₂(s) to Mn⁺⁷ under any of the thermodynamically favored conditions. Both KMn0₄ and Cl0₂ selectively oxidized reduced organic material before reducing the concentration of Mn². When C10₂ and KMnO₄ were added simultaneously, the ClO2 reacted preferentially with the reduced materials. Only after the Cl0₂ concentration was exhausted did the MnO₂⁻ begin to oxidize the reduced species. / Master of Science
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Treatment of algae-induced tastes and odors by chlorine, chlorine dioxide and permanganateBuffin, Lisa Webster 11 May 2010 (has links)
Chlorine (Cl₂(sq»' chlorine dioxide (ClO₂ ) and potassium permanganate (KMnO₄) were evaluated as oxidants for the removal of grassy and cucumber odors associated with the pure compounds, cis-3-hexenol and trans-2, cis-6-nonadienal, respectively, and for the removal of fishy odors associated with a culture of an alga, Synura petersenii. The effects of the oxidants on the pure compounds were assessed both by Flavor Profile Analysis (FPA) and gas chromatography/mass spectrometry (GC/MS). The effects of the oxidants on the algae culture were evaluated by FPA only. In addition, an unoxidized sample of Synura petersenii was analyzed by gas chromatography coupled with mass spectrometry (GC/MS) for possible identification of fishy-smelling compounds.
Chlorine (1-6 mg/L) and KMn04 (0.25-4 mg/L) markedly reduced grassy and cucumber odors associated with the two compounds. Gas chromatography/mass spectrometry confirmed that these compounds were reduced to below method detection limits. Levels of Cl₂(&q) required (up to 6 mg/L) to reduce the grassy odors associated with cis-3-hexenol were higher than those of KMnO₄ â ¢ The high Cl₂(&q) doses may have contributed to the formation of chemical odors observed by panelists. Two isomers of chlorohexenol were confidently identified as byproducts of cis-3-hexenol chlorination and may have contributed to the chemical odors that developed after CI2(aq) treatment. Chlorine and KMnO₄ (both at 10 mg/L) either reduced or destroyed the fishy odor associated with the culture of Synura petersenii; however, oxidation caused either the development or unmasking of fruity, cucumber, melon and grassy odors.
Chlorine dioxide (3 mg/L) did not reduce the grassy and cucumber odors associated with cis-3-hexenol and trans-2, cis-6-nonadienal , respectively. Gas chromatography and mass spectrometry confirmed that concentrations of these compounds were not reduced to below method detection limits. Furthermore, at a concentration of 10 mg/L, Cl₂ did not effectively reduce either the fishy or other objectionable odors associated with Synura petersenii culture.
Hexanal, with an odor described as "green" or "like lettuce heart," and trans-2, cis-6-nonadienal (cucumber odor) were confirmed as algal products in a two-week-old culture of Synura petersenii. In addition, decatrienal was confidently identified as a product of Synura and may have contributed to the fishy odor associated with this alga. / Master of Science
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Reactivity studies of arene-cis-diols in cycloadditions and potassium permanganate oxidations: synthesis of the corresponding arene-trans-diols and an approach to the synthesis of (+)-pancratistatinMcKibben, Bryan P. 06 June 2008 (has links)
Potassium permanganate oxidations and novel cycloaddition chemistry of the arene-cis-diols (7) were investigated. It was found that permanganate oxidation of arene-cis-diols yielded a mixture of 2 products, (157a) and (157b) in low yield. The influence of the C1-substituent on the outcome of the reaction was found to be a complex mixture of steric and electronic effects. In the area of cycloaddition chemistry of protected (7), this thesis describes novel [4+2] cycloadditions with quinones along with the first published report of benzyne and nitrile oxide cycloadditions of these homochiral molecules. The structure of the cycloadducts were elucidated by nOe as well as 2D-NMR analysis and were supported by Frontier Molecular Orbital theory. Finally, arene-trans-diols (200) were synthesized from (7) by a multistep stereoselective protection/deprotection sequence utilizing the Diels-Alder reaction. These compounds serve as intermediates in an approach to the amaryllidaceae alkaloid (+)-pancratistatin (12). / Ph. D.
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Analyse par spectrométrie de masse d’hormones stéroïdiennes dans les eaux usées et abattement par oxydation chimiqueFayad, Paul B. 12 1900 (has links)
No description available.
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