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Full-Text Articles in Engineering

Influence Of Photoreactor Design Parameters On The Performance Of Ultraviolet Light-Induced Degradation Of Per-And Polyfluoroalkyl Substances By Bismuth Oxy Hydroxy Phosphate And Hexagonal Boron Nitride Photocatalystsinfluence Of Photoreactor Design Parameters On The Performance Of Ultraviolet Light-Induced Degradation Of Per-And Polyfluoroalkyl Substances By Bismuth Oxy Hydroxy Phosphate And Hexagonal Boron Nitride Photocatalysts, Mojtaba Qanbarzadeh Dec 2023

Influence Of Photoreactor Design Parameters On The Performance Of Ultraviolet Light-Induced Degradation Of Per-And Polyfluoroalkyl Substances By Bismuth Oxy Hydroxy Phosphate And Hexagonal Boron Nitride Photocatalystsinfluence Of Photoreactor Design Parameters On The Performance Of Ultraviolet Light-Induced Degradation Of Per-And Polyfluoroalkyl Substances By Bismuth Oxy Hydroxy Phosphate And Hexagonal Boron Nitride Photocatalysts, Mojtaba Qanbarzadeh

All Dissertations

The main objective of this study is to evaluate the practical applicability of heterogeneous photocatalysis technology powered by ultraviolet (UV) photons for the degradation of per and -polyfluoroalkyl substances (PFAS) in contaminated groundwater samples. For this purpose, bismuth oxyhydroxy phosphate (BOHP) and hexagonal boron nitride (hBN) were utilized as the main photocatalysts in slurry photodegradation systems. BOHP (Bi3O(OH)(PO4)2) is a wide bandgap semiconductor with high activity for degrading long-chain perfluorocarboxylic acids (PFCAs) in mild operational conditions. Boron nitride (BN) is another wide bandgap semiconductor material that was used in this study due to its …


Nanobubble Technology For The Removal Of Mib And Geosmin From Drinking Water, Meryem Soyluoglu Dec 2023

Nanobubble Technology For The Removal Of Mib And Geosmin From Drinking Water, Meryem Soyluoglu

All Dissertations

The presence of taste and odor (T&O) compounds in drinking water has been historically a major challenge for water utilities. They are difficult to remove using conventional water treatment processes, a combination of coagulation, flocculation, sedimentation, filtration, and chlorination. However, activated carbon (AC) adsorption, advanced oxidation processes, and biofiltration can be effective. The seasonal nature of T&O events makes it difficult to justify installing dedicated treatment technologies. Additionally, incorporating these technologies into existing water treatment plants can be expensive and require significant upgrades. Therefore, water utilities are always interested in exploring new approaches to minimize the occurrence and removal of …


High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman Aug 2023

High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

All Dissertations

Atmospheric carbon dioxide (CO2) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO2 concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO2 concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …


Impact Of Granular Activated Carbon On In-Situ Reductive Dechlorination Of Chlorinated Solvents, Reagan Gregory Aug 2023

Impact Of Granular Activated Carbon On In-Situ Reductive Dechlorination Of Chlorinated Solvents, Reagan Gregory

All Theses

Treatment of chlorinated solvent-contaminated aquifers with in-situ activated carbon offers a simple yet cost-effective treatment opportunity, yet the interactions between activated carbon and the chlorinated solvents and their daughter products are not well understood.

The objective of this research is to demonstrate the impacts of in situ activated carbon on complete reductive dechlorination of chlorinated solvents in contaminated aquifer material with mixed dehalogenating cultures. This research seeks to characterize the sorption of trichloroethene and its daughter products cis-dichloroethene, vinyl chloride, and ethene to granular activated carbon and how that sorption relates to the removal of trichloroethene from contaminated material in …


The Potential Of Iron Electrodes In Electrochemical Cells For The Stabilization Of Synthetic Urine, Skyler Voisin Aug 2023

The Potential Of Iron Electrodes In Electrochemical Cells For The Stabilization Of Synthetic Urine, Skyler Voisin

All Theses

Source separation and urine treatment present the opportunity to significantly reduce influent concentrations of nitrogen and phosphorus in wastewater treatment plants and to capture those minerals for reuse. This study aims to use electrochemical cells with a sacrificial iron electrode to produce hydrogen peroxide in situ for the stabilization of urea while dissolving ferrous iron ions to promote the precipitation of phosphate into compounds such as vivianite (Fe3 (PO4)2 ∙ 8 H2O), a precipitate with potential uses in agriculture and manufacturing. Synthetic urine samples were treated as anolyte, then were given time to form …


Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling, Kaleb Boland Aug 2023

Investigation Into The Load Transfer Mechanism Of Trees To Develop An Innovative Foundation Configuration Using 3d Finite Element Modeling, Kaleb Boland

All Theses

This study was inspired by a tree’s reliance on its root system that enables it to withstand a natural disaster, such as an extreme hydroclimatic event or hurricane. This curiosity has led to an investigation into what makes this possible, developing a new and innovative foundation configuration for infrastructure systems, and a new possible construction material and method. This study provides results on a material that does not have conventional testing procedures or standards: a tree root. The trees studied are common to the upstate of South Carolina, which are Pine, Sweetgum, and White Oak. According to the results, on …


Improvement Of A Low-Cost Diy Wave Gauge, Matthew F. Virden, Nigel A. Temple, Bret M. Webb, Eric L. Sparks May 2023

Improvement Of A Low-Cost Diy Wave Gauge, Matthew F. Virden, Nigel A. Temple, Bret M. Webb, Eric L. Sparks

The Journal of Extension

The impacts of waves on shorelines and nearshore ecosystems has highlighted the need for extension and other environmental professionals to have access to accurate and affordable wave measurements. The development of a low-cost DIY wave gauge improved the accessibility of these measurements; however, the original design was limited in battery life. Here, an improved version of the low-cost DIY wave gauge, the DIY Feather Wave Gauge, is presented with the same performance, longer battery life, smaller design, and cheaper cost along with tutorials, parts lists, and other resources. This new gauge has been used to improve shoreline management recommendations.


Computational Modeling Of Patterned Membranes And Spacers For Improved Hydrodynamics And Fouling Reduction In Reverse Osmosis Water Treatment Processes, Zuo Zhou May 2023

Computational Modeling Of Patterned Membranes And Spacers For Improved Hydrodynamics And Fouling Reduction In Reverse Osmosis Water Treatment Processes, Zuo Zhou

All Dissertations

My research goal is to discover ways to improve the hydrodynamics of reverse osmosis (RO) membrane systems through creative membrane surface patterning and spacer designs. Since concentration polarization (CP) usually promotes membrane fouling, improving hydrodynamics would result in reduced fouling and better membrane performance. With computational fluid dynamics (CFD), we can explore dozens or even hundreds of models with different geometries and boundary conditions. Through plotting their velocity profile, streamlines, shear stress, pressure profile, concentration profile, and so on, we can determine which design would lead to the best performance.

At first, patterned membranes were evaluated and compared with flat …


Evaluating The Effect Of Palmitic Acid Concentration On Growth And Inhibition Of Syntrophomonas Sp., Clancy Kerr May 2023

Evaluating The Effect Of Palmitic Acid Concentration On Growth And Inhibition Of Syntrophomonas Sp., Clancy Kerr

All Theses

Various industries produce fats, oils, and greases (FOG). These hydrophobic compounds cause issues in municipal wastewater collection and treatment systems. Anaerobic co-digestion is an effective way to treat FOG and presents an opportunity to produce more significant quantities of biogas. However, many microorganisms are sensitive to the degradation products like long-chain fatty acids (LCFAs). Palmitic acid is the most prevalent LCFA in anaerobic co-digestion of FOG and wastewater. Sytrophomonas is a β-oxidizer able to break down palmitic acid. Palmitic acid is known to feed and inhibit Syntrophomonas growth and methanogenesis. The objectives of this investigation are: To determine if Syntrophomonas …


Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris May 2023

Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris

All Theses

Since the 1950s, the United States has produced approximately 90,000 metric tons of spent nuclear fuel (SNF) (Office of Nuclear Energy, 2022); however, no long-term storage solutions are available. Technecium-99 and neptunium-237, two fission products found in SNF, readily form highly mobile species in oxidizing conditions (Hu, 2008; Bondietti, 1979) and have respective half-lives of 2.13 x 105 and 2.14 x106 years (Hu, 2010). Considering these characteristics, 99Tc and 237Np are two risk-driving isotopes found in SNF storage. The process of macropore-facilitated preferential flow, transport through cracks within a soil matrix, has been recognized to increase …


Evaluating The Role Of Magnetic Materials In Mediating The Abiotic Degradation Of Chlorinated Ethenes At Tcaap-A Using A C14-Assay, Olivia Dunn May 2023

Evaluating The Role Of Magnetic Materials In Mediating The Abiotic Degradation Of Chlorinated Ethenes At Tcaap-A Using A C14-Assay, Olivia Dunn

All Theses

Among the most challenging sites to remediate are those where the groundwater is contaminated with large, dilute plumes of tetrachloroethene (PCE), trichloroethene (TCE), dichloroethene isomers (cDCE, tDCE, 1,1-DCE) and vinyl chloride (VC). Monitored Natural Attenuation (MNA) by abiotic processes may be a viable strategy, but it can be difficult to document. The overall objective of this project is to develop a deeper understanding of the role of magnetic materials in mediating abiotic degradation of low concentrations of chlorinated ethenes in aquifers. Authentic core aquifer sediment has been collected from Site A at the former Twin Cities Army Ammunition Plant (TCAAP) …


Ligand-Promoted Dissolution Of Uranyl Phosphate Across Scales, Brennan Ferguson Dec 2022

Ligand-Promoted Dissolution Of Uranyl Phosphate Across Scales, Brennan Ferguson

All Dissertations

The formation of uranyl phosphate precipitate is a remediation strategy because the low solubility of uranyl phosphate minerals, like chernikovite, limits the mobility of uranium in contaminated soils. However, organic ligands can complex with aqueous metal cations to form more soluble species. For example, citrate is a commonly occurring organic ligand produced by plants and microbes that increases the solubility of uranium and therefore the dissolution of uranyl phosphate minerals in the uranyl phosphate-citrate system. This effect is an important control on the mobility of uranium in organic-rich, and near-surface vegetated environments. Nevertheless, key aspects of the citrate-uranyl phosphate system …


Mysteerio: Multi-Regional Environmentally Extended Input-Output Model For United States, Yash Srivastava Dec 2022

Mysteerio: Multi-Regional Environmentally Extended Input-Output Model For United States, Yash Srivastava

All Theses

This research work titled My State Environmentally Extended Regional Input-Output (MYSTEERIO) is based on the concept of multi-regional environmentally extended input-output (MREEIO), which is a combination of lifecycle thinking and economics principles. Numerous studies have highlighted the advantages of using this methodology to determine the environmental impacts associated with economic activities for a region. However, no prior attempt has been made to conduct a state-level analysis for the US. This research work thus tries to estimate the impacts embodied due to the consumption of goods and services at the state level by using the MREEIO principles. Extensive coverage of the …


Microcosm Evaluation Of Natural And Biologically-Enhanced Abiotic Transformation Of Chlorinated Ethenes In Low Permeability Formations, Hao Wang Dec 2022

Microcosm Evaluation Of Natural And Biologically-Enhanced Abiotic Transformation Of Chlorinated Ethenes In Low Permeability Formations, Hao Wang

All Dissertations

Trichloroethene (TCE) is one of the most commonly found hazardous compounds at Superfund sites, especially in groundwater. Its volatility and toxicity pose a threat to drinking water safety and human health. In the past decades, research on the fate of TCE in the environment has shifted to contamination of low-permeability formations, for example fractured bedrock aquifers. TCE back-diffusion from low permeability zones and management of persistent TCE groundwater plumes caused by this long-term source zone pose major challenges for remediation.

Monitored natural attenuation (MNA) is a cost-effective remediation strategy that has gradually gained acceptance by regulators. Compared to extensive active …


Integration Of Techno-Economic Analysis (Tea) And Life Cycle Assessment (Lca) For Sustainable Process Design, Roksana Mahmud Aug 2022

Integration Of Techno-Economic Analysis (Tea) And Life Cycle Assessment (Lca) For Sustainable Process Design, Roksana Mahmud

All Dissertations

For sustainable design, technology developers need to consider not only technical and economic aspects but also potential environmental impacts while developing new technologies. Techno-economic analysis (TEA) evaluates the technical performance and economic feasibility of a technology. Life cycle assessment (LCA) evaluates the potential environmental impacts associated with a product system throughout its life cycle from raw material extraction to disposal. Generally, TEA and LCA are performed separately for technology assessment. Understanding of the trade-off between economic and environmental performances is crucial for sustainable process design, which is not fully available if TEA and LCA is performed separately. In contrast, integration …


Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome Aug 2022

Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome

All Theses

Current biological strategies for remediating trichloroethylene (TCE) in low pH aquifers (i.e., pH14C-TCE assay was developed to determine pseudo first-order rate constants for the degradation of TCE in microcosms containing soil and groundwater from the Boeing Michigan Aeronautical Research Center (BOMARC) superfund site, where the pH ranges from 4.1 to 4.9. The 14C-TCE assay was also adapted to calculate soil-normalized rate constants for data from this site, as well as data that Szwast21 collected from the Beltsville Agricultural Research Center (BARC). In addition to natural attenuation, biostimulation through amendments of methane and nutrients were also assessed. This treatment …


An Evaluation Of Energy Consumption Comparing Conventional Water Treatment Plants To Microfiltration And Ultrafiltration Water Treatment Plants, Danielle Larsen Aug 2022

An Evaluation Of Energy Consumption Comparing Conventional Water Treatment Plants To Microfiltration And Ultrafiltration Water Treatment Plants, Danielle Larsen

All Theses

The use of low-pressure, hollow fiber microfiltration (MF) and ultrafiltration (UF) membranes has become increasingly prominent in drinking water treatment plant configurations over the past 30 years. At the same time, the topics of energy efficiency and sustainability in industry are becoming progressively more important. Although MF and UF are highly successful in filtration, they are generally thought of as significant energy consumers; however, the data have not yet been available to compare multiple plants in various contexts to determine the factors that most affect energy use. This research compares the energy use of MF and UF treatment plants to …


Use Of A Trial Function Method To Semi-Analytically Simulate Matrix Diffusion In Heterogeneous And Fractured Media, Kien Trung Pham Aug 2022

Use Of A Trial Function Method To Semi-Analytically Simulate Matrix Diffusion In Heterogeneous And Fractured Media, Kien Trung Pham

All Dissertations

A semi-analytic trial function model is applied to simulate matrix diffusion in systems of parallel fractures, 2-D/3-D discrete fracture networks, and in 3-D heterogeneous media. The trial function model gives low normalized root mean square error (NRMSE) when compared to the parallel fracture analytical solution over a range of fracture spacing, with considerations for retardation and decay. The semi-analytic trial function model is efficient in time and maintains less than 6% NRMSE when it simulates matrix diffusive transport in 2-D/3-D discrete fracture networks (DFN). The model can predict DFN plume within a few meters of accuracy compared to fine-grid DFN …


Characterization Of Water Flow And Solute Transport Driven By Preferential Flow In Soil Vadose Zone, Abdullah Al Mamun May 2022

Characterization Of Water Flow And Solute Transport Driven By Preferential Flow In Soil Vadose Zone, Abdullah Al Mamun

All Dissertations

The vadose zone acts as a buffer zone between the ground surface and the aquifers underneath and controls the transmission of infiltrating water and contaminants, for example, pesticides and chemical spills. Therefore, understanding the flow and transport processes that dominate the vadose zone is important. Macropores are ubiquitous and particularly found in abundance in the vadose zone. These macropores facilitate preferential flow, through which water travels rapidly deep into the soil, bypassing most of the porous matrix. Preferential flow and transport have environmental significance as their processes impact hydrology, ecology, agriculture, subsurface contamination, and waste management sectors. Thus, the overall …


The Control Strategies Of Brominated Organic Disinfection By-Products: Adsorption With Pre-Chlorination And Photodegradation, Cagri Utku Erdem May 2022

The Control Strategies Of Brominated Organic Disinfection By-Products: Adsorption With Pre-Chlorination And Photodegradation, Cagri Utku Erdem

All Dissertations

Increasing water pollution, scarcity, and seasonal events force water treatment plants to improve existing treatment techniques and/or implement new methods to enhance drinking water treatment and comply with disinfection by-product (DBP) regulations. A limited number of studies examine the pre-chlorination prior to activated carbon (AC) adsorption for the removal of DBP precursors, and there are no comprehensive and representative treatment conditions in current literature. Although many studies investigated photodegradation of individual DBPs by low pressure ultraviolet (UV254) light, there is still lack of information and limited understanding of photodegradation of total organic halogens and practical implications of UV …


Floating Treatment Wetlands For Brackish Waters: Plant Selection And Nutrient Uptake Potential., Andrea Landaverde May 2022

Floating Treatment Wetlands For Brackish Waters: Plant Selection And Nutrient Uptake Potential., Andrea Landaverde

All Theses

Brackish water bodies in coastal regions provide critical ecosystem services that support human and environmental health. Anthropogenic activities such as agricultural and industrial activities, construction, urban settlements, and tourism contribute to increased inputs of nitrogen (N) and phosphorus (P) in brackish coastal ecosystems. Excess nutrients can lead to impaired water quality and affect marine organisms. Floating treatment wetlands (FTWs) are a vegetated-base technology used to remove contaminants from water column, that has been mainly studied and applied in freshwater systems. Application of FTWs in brackish systems requires further investigation, as high salinity in brackish waters could result in toxicity to …


Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano May 2022

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …


Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker May 2022

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

All Dissertations

Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …


Effect Of Long And Short Chain Fatty Acids On Methane Yield And Microbial Community Composition In Anaerobic Co-Digestion, Emmaline Spier Camposano Dec 2021

Effect Of Long And Short Chain Fatty Acids On Methane Yield And Microbial Community Composition In Anaerobic Co-Digestion, Emmaline Spier Camposano

All Theses

Fats, oils and greases are produced from a variety of industries, including animal rendering operations, vegetable oil processing plants and the hospitality industry. These hydrophobic, COD-rich compounds are known to cause issues in municipal wastewater collection and treatment systems. Anaerobic co-digestion has been shown to be an effective way to treat FOG and presents an opportunity to produce greater quantities of biogas. However, many microorganisms are sensitive to the degradation products of FOG, including long and short chain fatty acids. Two studies were performed to address potential inhibitory effects of both.

The first study co-digested various percentages of FOG with …


Development And Validation Of An Analytical Modeling Tool For Solar Borehole Heat Exchangers, Adam Ornelles Dec 2021

Development And Validation Of An Analytical Modeling Tool For Solar Borehole Heat Exchangers, Adam Ornelles

All Theses

Current numerical modeling solutions used for subsurface heat flow, such as the Berkeley TOUGH codes, are often difficult to use and time-consuming compared to analytical modeling methods. However, current analytical modeling methods for subsurface heat flow and groundwater cannot accurately model the subsurface in 3 dimensions, a feature paramount to the planning and installation of thermal borehole heat exchangers used in environmental remediation.

This research developed a novel 3-dimensional analytical modeling tool for solar-powered borehole heat exchangers. The analytical modeling tool can plan thermal remediation systems while being more straightforward to operate than current numerical modeling software. By creating a …


The Effect Of Using Palm Oil As An Electron Donor For The Reductive Dechlorination Of Trichloroethylene (Tce), Shivani Swamy Dec 2021

The Effect Of Using Palm Oil As An Electron Donor For The Reductive Dechlorination Of Trichloroethylene (Tce), Shivani Swamy

All Theses

TCE is currently remediated using physical methods like air stripping and granular activated carbon adsorption. While physical and chemical processes work on a site-specific basis, biological strategies have been favored as they are economical and reliable. The objective of this work was to determine the feasibility of using palm oil as an electron donor in the reductive dechlorination of TCE to ethene. Palm oil was considered for the study because it is locally grown in many parts of the world. The palm oil that does not meet the industry standards is discarded. Despite the environmental impacts caused by the palm …


Increase In The Reduction Potential Of Uranyl Upon Interaction With Graphene Oxide Surfaces, V. N. Bliznyuk, N. Conroy, Y. Xie, R. Podila, A. Rao, Brian A. Powell Dec 2017

Increase In The Reduction Potential Of Uranyl Upon Interaction With Graphene Oxide Surfaces, V. N. Bliznyuk, N. Conroy, Y. Xie, R. Podila, A. Rao, Brian A. Powell

Publications

Coordination of uranyl (U(VI)) with carboxylate groups on functionalized graphene oxide (GO) surfaces has been shown to alter the reduction potential of the sorbed uranium ion. A quantitative measure of the reduction potential and qualitative estimation of sorption/desorption processes were conducted using cyclic voltammetry, and the proposed coordination environment was determined using the surface sensitive attenuated total reflection mode of infrared spectroscopy (ATR-FTIR). GO is a nanostructured material possessing a large amount of oxygen-containing functional groups both on basal planes and at the edges, which can form strong surface complexes with radionuclides. The presence of these functional groups on the …


Electrochemical Enhancement Of Butanol Production And Xylose Consumption In Pure And Mixed Culture Fermentations, Jovan Popovic Dec 2015

Electrochemical Enhancement Of Butanol Production And Xylose Consumption In Pure And Mixed Culture Fermentations, Jovan Popovic

All Dissertations

The volatility of foreign and domestic petroleum markets has prompted initiatives for the development of alternative liquid energy carriers which have the capacity to accommodate our current transportation infrastructure. Butanol, which has an energy density similar to that of gasoline and can be produced through the fermentation of carbohydrates by solventogenic Clostridia, has been investigated as a supplement or direct replacement to gasoline. However, most butanol fermentations rely on glucose as a feedstock which is in direct competition with our food supply, and this requires the exploration of alternative fermentable substrates. This study investigates the use of electrochemical fermentation modifications …


Bromide Removal From Surface Waters By Silver Impregnated Activated Carbon, Chen Chen Jan 2015

Bromide Removal From Surface Waters By Silver Impregnated Activated Carbon, Chen Chen

All Theses

Bromide is a precursor of disinfection by-products (DBPs) during potable water treatment, because it causes the formation of brominated DBPs that are more cyto- and geno-toxic than their chlorinated analogues. Due to the potential health risks of DBPs, the United States Environmental Protection Agency (USEPA) has been imposing increasingly stringent regulations for controlling the DBPs. Therefore, removal of bromide ions from source waters becomes critical for controlling the DBPs formation. In my study, it was hypothesized that silver impregnated activated carbon (SIAC) can be a promising adsorbent for bromide removal from water. The main research objectives of this study were …


Optimizing Light Collection From Extractive Scintillating Resin In Flow-Cell Detectors, Amy Meldrum Dec 2014

Optimizing Light Collection From Extractive Scintillating Resin In Flow-Cell Detectors, Amy Meldrum

All Theses

The objectives of this study were to investigate the changes in light collection efficiency for flow cell detector as various parameters are altered to find the optimum flow cell configuration. Columns with inner diameters of 0.16 cm, 0.48 cm, 0.79 cm, and 1.11 cm were packed with synthesized nonporous, un-functionalized beads to measure their detection efficiencies for solutions containing 210Po, 14C, or 90Sr/90Y. The average diameter of the beads used in the experiments was 147 µm ± 33 µm. The highest detection efficiency for 210Po was 15.3 ± 3.9% with the 1.11 cm diameter column. The 1.11 cm diameter column …