Efficient Removal Of Chemical Organic Demand And Total Organic Carbon From Leachate Using Heterogeneous Fenton Catalyst Based On Activated Carbon,
2024
Research Unit: Materials, Processes and Environment, Faculty of Technology, M’hamed Bougara University, Boumerdes 35000, Algeria
Efficient Removal Of Chemical Organic Demand And Total Organic Carbon From Leachate Using Heterogeneous Fenton Catalyst Based On Activated Carbon, Amar Idir, Mounir Ziati, Mohamed Bouzid
Emirates Journal for Engineering Research
Organic components contained in leachates resulting from decomposition of waste are difficult to degrade. Leachate volume and its composition vary depending on biogeochemistry of site type of deposited residues, and the age of sanitary landfill. The present study aims to develop efficient heterogeneous Fenton oxidation of organic matter, expressed in terms of chemical organic demand (COD) and total organic carbon (TOC) of leachate using the newly synthesized iron-modified activated carbon. The characterization of catalyst revealed that the Fe(II) was successfully introduced onto the original activated carbon (AC) and diversified the material’s surface morphology and elemental compounds. The heterogeneous Fenton oxidation …
Advanced Oxidation Of Tert-Butanol With Ultraviolet Light Emitting Diodes And Hydrogen Peroxide,
2024
Air Force Institute of Technology
Advanced Oxidation Of Tert-Butanol With Ultraviolet Light Emitting Diodes And Hydrogen Peroxide, Lauren R. Mainolfi
Theses and Dissertations
Tert-butanol (TBA), a versatile chemical widely used in industrial processes, poses exposure risks through inhalation, ingestion, and skin contact. Environmental contamination, often from industrial activities, emphasizes the importance of robust waste management and monitoring to protect water supplies from potential TBA migration and ensure drinking water safety. This study employed hydrogen peroxide (H2O2): TBA molar ratios of 100, 200, 400, and 500:1 in a Continuous Flow Stirred-Tank Reactor (CSTR) with UV-LED as the TBA degradation mechanism in an Advanced Oxidation Process (AOP). The UV-LEDs and H2O2 were synergistically employed to generate hydroxyl radicals in an advanced oxidation process. Gas chromatography–mass …
Advanced Oxidation Of Methyl Tert Butyl Ether With Ultraviolet Light Emitting Diodes,
2024
Air Force Institute of Technology
Advanced Oxidation Of Methyl Tert Butyl Ether With Ultraviolet Light Emitting Diodes, Aaron R. Neal
Theses and Dissertations
Methyl Tert-Butyl Ether (MTBE) is a volatile, soluble, organic compound introduced to gasoline within the United States as a fuel oxygenator in 1979. MTBE is a common groundwater pollutant due to its high water solubility and resistance to bio-degradation; it commonly infiltrates groundwater sources via leaking underground storage tanks or fuel spills. This research employed ultraviolet light emitting diodes (UV-LEDs) and hydrogen peroxide (H2O2) induced advanced oxidation process (AOP) to treat MTBE contaminated water at the bench scale. Using four H2O2:MTBE molar peroxide ratios (100:1, 200:1, 400:1, 500:1), MTBE degradation was induced …
Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models,
2024
Colorado State University - Fort Collins
Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …
Lotic-Sipco2: Adaptation Of An Open-Source Co2 Sensor System And Examination Of Associated Emission Uncertainties Across A Range Of Stream Sizes And Land Uses,
2024
Ecole Polytechnique Fédérale de Lausanne
Lotic-Sipco2: Adaptation Of An Open-Source Co2 Sensor System And Examination Of Associated Emission Uncertainties Across A Range Of Stream Sizes And Land Uses, Andrew L. Robison, Lauren E. Koenig, Jody D. Potter, Lisle E. Snyder, Christopher W. Hunt, William H. Mcdowell, Wilfred M. Wollheim
Faculty Publications
River networks play a crucial role in the global carbon cycle, as relevant sources of carbon dioxide (CO2) to the atmosphere. Advancements in high-frequency monitoring in aquatic environments have enabled measurement of dissolved CO2 concentration at temporal resolutions essential for studying carbon variability and evasion from these dynamic ecosystems. Here, we describe the adaptation, deployment, and validation of an open-source and relatively low-cost in situ pCO2 sensor system for lotic ecosystems, the lotic-SIPCO2. We tested the lotic-SIPCO2 in 10 streams that spanned a range of land cover and basin size. Key system adaptations for lotic environments included prevention of biofouling, …
Univariate Optimization Of Dispersive Liquid-Liquid Microextraction For Preconcentration Of Lead From Environmental Matrices, Samawah Region Prior To Quantification Using Flame Atomic Absorption Spectroscopy,
2024
Department of Chemistry, College of Science, University of Thi-Qar, Thi-Qar, 64001, Iraq.
Univariate Optimization Of Dispersive Liquid-Liquid Microextraction For Preconcentration Of Lead From Environmental Matrices, Samawah Region Prior To Quantification Using Flame Atomic Absorption Spectroscopy, Zaman Sahb Mehdi, Saher A. Ali Alshamkhawy
Al-Bahir
In this work, a procedure based on dispersive liquid₋liquid microextraction for lead (Pb) preconcentration and quantification in an environmental matrix by flame atomic absorption spectroscopy (FAAS) was applied. A case-study approach was chosen to obtain further in-depth information on the Pb levels. The green chemistry principles have been applied for the pretreatment and preparation of real samples by focusing on some features such as the volume of reagents/sample, employ of energy efficient equipment, and production of waste. A univariate strategy was utilized to achieve the optimum extraction conditions. 1750 µL of acetonitrile containing 100 µL of carbon tetrachloride, were rapid …
Sulfate Enhances The Adsorption And Retention Of Cu(Ii) And Zn(Ii) To Dispersed And Aggregated Iron Oxyhydroxide Nanoparticles,
2024
University of Pennsylvania
Sulfate Enhances The Adsorption And Retention Of Cu(Ii) And Zn(Ii) To Dispersed And Aggregated Iron Oxyhydroxide Nanoparticles, Emma M. Kocik, Abigail Kim, Miranda L. Aiken, Lauren Smith, Christopher S. Kim
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The adsorption and retention of metal ions to nanoscale iron (hydr)oxides in aqueous systems is significantly influenced by prevailing environmental conditions. We examined the influence of sulfate, the second most common anion in seawater that is present in many other natural aquatic systems, on the adsorption and retention of Cu(II) and Zn(II) to synthetic iron oxyhydroxide nanoparticles (NPs) and their aggregates. Batch uptake experiments with monodisperse NPs and NPs aggregated by changes in pH, ionic strength, and temperature were conducted over sulfate concentrations ranging from 0 to 0.30 M. The introduction of 0.03 M sulfate significantly increased the initial adsorption …
Simple Sars-Cov-2 Concentration Methods For Wastewater Surveillance In Low Resource Settings,
2024
University of Kentucky
Simple Sars-Cov-2 Concentration Methods For Wastewater Surveillance In Low Resource Settings, Mohammad Dehghan Banadaki, Soroosh Torabi, Alexus Lori Rockward, William Strike, Ann Noble, James W. Keck, Scott M. Berry
UK CARES Faculty Publications
Wastewater-based epidemiology (WBE) measures pathogens in wastewater to monitor infectious disease prevalence in communities. Due to the high dilution of pathogens in sewage, a concentration method is often required to achieve reliable biomarker signals. However, most of the current concentration methods rely on expensive equipment and labor-intensive processes, which limits the application of WBE in low-resource settings. Here, we compared the performance of four inexpensive and simple concentration methods to detect SARS-CoV-2 in wastewater samples: Solid Fraction, Porcine Gastric Mucin-conjugated Magnetic Beads, Calcium Flocculation- Citrate Dissolution (CFCD), and Nanotrap® Magnetic Beads (NMBs). The NMBs and CFCD methods yielded the highest …
Thin-Film Nanocomposite Membranes With Alumina Nanoparticles For Textile Wastewater Treatment Applications,
2024
American University in Cairo
Thin-Film Nanocomposite Membranes With Alumina Nanoparticles For Textile Wastewater Treatment Applications, Amr Mohamed Tayel
Theses and Dissertations
Thin-film nanocomposite (TFN) membranes are gaining great interest in industrial wastewater treatment due to their superior performance, especially for higher water flux and pollutants’ rejection, as well as improved chemical, thermal and mechanical stabilities, compared to other types of membranes. The performance of TFN membranes can be enhanced using different types of nanofillers, among which ceramic nanomaterials, such as Al2O3, offer a promising potential for applications involving treatment of industrial wastewater such as textile effluents, and this is due to their stability, hydrophilicity, and relative low cost. The study of the TFN membrane properties and structure allows the optimization and …
Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements,
2024
South Dakota State University
Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar
Electronic Theses and Dissertations
Perchlorate, which derives from both anthropogenic and natural sources in the current environment, poses a substantial health hazard to humans as it competes with iodine uptake in the thyroid gland. Consequently, there has been considerable concern about minimizing human exposure to environmental perchlorate by restricting its release from man-made sources. However, the absence of a clear understanding regarding the respective contributions of man-made and natural sources has hindered widespread regulation efforts. A 300-year (1700–2007) Summit, Greenland ice core record from a previous study showed relatively stable perchlorate concentrations in Greenland snow prior to 1980, with some elevated perchlorate levels associated …
Assessment Of The Extraction And Quantification Of Pfbs From Sprague Dawley Rat Adipose Tissues,
2024
Georgia Southern University
Assessment Of The Extraction And Quantification Of Pfbs From Sprague Dawley Rat Adipose Tissues, Joshua O. Osaghae
Honors College Theses
Per- and polyfluoroalkyl substances (PFAS) are a group of complex synthetic chemicals that have applications ranging from automotives to consumer products. PFAS have been found to bioaccumulate in the ecosystem as their carbon-fluorine bonds are among the strongest bonds in organic chemistry. Perfluorobutanesulfonic acid (PFBS) compounds are used as surfactants in water- and stain-repellent coatings for fabrics and carpets, cleaning agents, and paints. The persistence of PFAS has led to their accumulation in sources of groundwater, making them ubiquitous drinking water contaminants of concern with evidence linking PFAS exposure to adverse health effects, including reduced kidney function, thyroid disruption, and …
The Effect Of Ions On The Adsorption Of So2 On A Water Nanoparticle,
2024
Western Kentucky University
The Effect Of Ions On The Adsorption Of So2 On A Water Nanoparticle, Nathaniel W. Gillispie
Mahurin Honors College Capstone Experience/Thesis Projects
Secondary Organic Aerosols (SOAs) have been of interest to atmospheric chemists for their harmful effects on human health and implications for climate change. Here, we explore a likely system from the early stages of SOA formation. Using compu- tational methods, water nanoparticles with and without ions were simulated. We observe the effects of ions on the adsorption of SO2 on this system. SO2 in the at- mosphere is associated with greater production of SOAs, so its study is important to SOA formation. We find that the overall structure of water is the most important observable affecting the location of SO2 …
Permafrost Carbon: Progress On Understanding Stocks And Fluxes Across Northern Terrestrial Ecosystems,
2024
Alfred Wegener Institute Helmholtz Center for Polar and Marine Research
Permafrost Carbon: Progress On Understanding Stocks And Fluxes Across Northern Terrestrial Ecosystems, Claire C. Treat, Anna-Maria Virkkala, Eleanor Burke, Lori Bruhwiler, Abhishek Chatterjee, Joshua B. Fisher, Josh Hashemi, Frans-Jan W. Parmentier, Brendan M. Rogers, Sebastian Westermann, Jennifer D. Watts, Elena Blanc-Betes, Matthias Fuchs, Stefan Kruse, Avni Malhotra, Kimberley Miner, Jens Strauss, Amanda Armstrong, Howard E. Epstein, Bradley Gay, Mathias Goeckede, Aram Kalhori, Dan Kou, Charles E. Miller, Susan M. Natali, Youmi Oh, Sarah Shakil, Oliver Sonnentag, Ruth K. Varner, Scott Zolkos, Edward A.G. Schuur, Gustaf Hugelius
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Significant progress in permafrost carbon science made over the past decades include the identification of vast permafrost carbon stocks, the development of new pan-Arctic permafrost maps, an increase in terrestrial measurement sites for CO2 and methane fluxes, and important factors affecting carbon cycling, including vegetation changes, periods of soil freezing and thawing, wildfire, and other disturbance events. Process-based modeling studies now include key elements of permafrost carbon cycling and advances in statistical modeling and inverse modeling enhance understanding of permafrost region C budgets. By combining existing data syntheses and model outputs, the permafrost region is likely a wetland methane …
Geochemistry Of Rare Earth Elements In Simulated Natural Waters: Experiments And Modelling Of Precipitation, Complexation, And Bioavailability.,
2024
Wilfrid Laurier University
Geochemistry Of Rare Earth Elements In Simulated Natural Waters: Experiments And Modelling Of Precipitation, Complexation, And Bioavailability., Samantha Zulian
Theses and Dissertations (Comprehensive)
Rare earth elements (REEs) are an important part of modern technology and used for many applications. Mining, agriculture, improper recycling and medical applications can increase the concentration of these elements in surface waters. Metals in the environment including REEs can be found naturally but understanding the implications increase concentrations from anthropogenic inputs is important. REE mobility, persistence and toxicity is imperative to risk assessment as Canada begins to mine REE. Ultimately, as with other metals, the impacts of REEs in the environment should be dependent on the specific physical and chemical forms of the elements. Fractionation provides a practical method …
Mapping The Reaction Networks Of Cis Formed In The Ozone-Assisted Oxidation Of C₆ Acyclic And Endocyclic Alkenes,
2024
University of Central Florida
Mapping The Reaction Networks Of Cis Formed In The Ozone-Assisted Oxidation Of C₆ Acyclic And Endocyclic Alkenes, Zachary Clarke
Honors Undergraduate Theses
Criegee intermediates (CIs) are highly reactive species generated during the ozonolysis of alkenes, exerting a critical influence on atmospheric oxidation, combustion chemistry, and synthetic processes. Their reactivity, encompassing unimolecular and bimolecular pathways, shapes oxidation mechanisms and product distributions in these environments. A key determinant of CI behavior is the structural nature of the parent alkene. Acyclic alkenes typically yield intermediates with minimal steric hindrance, facilitating rapid reactions, whereas endocyclic alkenes produce geometrically constrained CIs with enhanced internal stabilization, redirecting reaction pathways and reducing overall reactivity. Despite their importance, mechanistic understanding remains limited due to experimental challenges in detecting CIs and …
Wildfire Effects On The Fate Of Deposited Nitrogen In A Boreal Larch Forest,
2024
Fujian Polytechnic Normal University
Wildfire Effects On The Fate Of Deposited Nitrogen In A Boreal Larch Forest, Weili Liu, Jiaxing Zu, B. Liu, Lin Qi, Wei Huang, Yunting Fang, Jian Yang
Earth and Environmental Sciences Faculty Publications
The effects of nitrogen (N) deposition on forests largely depend on the ecosystem N status and the fates of deposited N. Boreal forests are typically N-limited ecosystems and are considered to be more efficient in retaining deposited N relative to temper- ate and tropical forests. As a primary disturbance in boreal forests, wildfires may alleviate N limitation in the burned ecosystem and increase mineralization, resulting in the altered outcomes of the N deposition.
The Surface Chemistry And Binding Interactions Of Lignin With Polymer-Encapsulated Gold Nanoparticles Acting As Model Microplastics,
2024
Central Washington University
The Surface Chemistry And Binding Interactions Of Lignin With Polymer-Encapsulated Gold Nanoparticles Acting As Model Microplastics, Oluwaseun Ayodeji Akinsola
All Master's Theses
This study investigates the surface chemistry and molecular-level interactions between lignin, a special type of natural organic matter, and polymer-capped gold nanoparticles, shedding light on the strength of adsorption between lignin and nanoscale polymer surfaces. Specifically, the study presents a variety of nanoscale polymer surfaces displaying different charged functional groups, using layer-by-layer assembly of three polyelectrolytes (polyallylamine hydrochloride (PAH)), polyacrylic acid (PAA), and poly(diallyldimethylammonium chloride (PDADMAC)) on 90 nm citrate-stabilized gold nanoparticles (AuNPs). This approach provides a library of polymer-encapsulated AuNPs for investigating the binding interactions of lignin to nanoscale polymers via spectroscopic techniques. ζ-potential, dynamic light scattering (DLS), …
Stabilization Of Pfas-Contaminated Soil With Sewage Sludge- And Wood-Based Biochar Sorbents,
2024
Norwegian Geotechnical Institute
Stabilization Of Pfas-Contaminated Soil With Sewage Sludge- And Wood-Based Biochar Sorbents, Erlend Sørmo, Clara Benedikte Mader Lade, Julie Zhang, Alexandros G. Asimakopoulos, Geir Wold Åsli, Michel Hubert, Aleksandar I. Goranov, Hans Peter H. Arp, Gerard Cornelissen
Chemistry & Biochemistry Faculty Publications
Sustainable and effective remediation technologies for the treatment of soil contaminated with per- and polyfluoroalkyl substances (PFAS) are greatly needed. This study investigated the effects of waste-based biochars on the leaching of PFAS from a sandy soil with a low total organic carbon content (TOC) of 0.57 ± 0.04% impacted by PFAS from aqueous film forming foam (AFFF) dispersed at a former fire-fighting facility. Six different biochars (pyrolyzed at 700–900°C) were tested, made from clean wood chips (CWC), waste timber (WT), activated waste timber (aWT), two digested sewage sludges (DSS-1 and DSS-2) and de-watered raw sewage sludge (DWSS). Up-flow column …
Unraveling Sources Of Cyanate In The Marine Environment: Insights From Cyanate Distributions And Production During The Photochemical Degradation Of Dissolved Organic Matter,
2024
Shandong University
Unraveling Sources Of Cyanate In The Marine Environment: Insights From Cyanate Distributions And Production During The Photochemical Degradation Of Dissolved Organic Matter, Rui Wang, Jihua Liu, Yongle Xu, Li Liu, Kenneth Mopper
Chemistry & Biochemistry Faculty Publications
Cyanate is a nitrogen and energy source for diverse marine microorganisms, playing important roles in the nitrogen cycle. Despite the extensive research on cyanate utilization, the sources of this nitrogen compound remain largely enigmatic. To unravel the sources of cyanate, distributions and production of cyanate during photochemical degradation of natural dissolved organic matter (DOM) were investigated across various environments, including freshwater, estuarine, coastal areas in Florida, and the continental and slope regions of the North American mid-Atlantic Ocean (NATL). Cyanate production was also examined during the photochemical degradation of exudates from a typical strain of Synechococcus, an important phytoplankton …
Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation,
2024
Old Dominion University
Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher
Chemistry & Biochemistry Faculty Publications
With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC). Traditionally, wildfire research has assumed that condensed aromatic carbon (ConAC) is exclusively produced via combustion, and thus, ConAC is equated to BC. However, the lack of correlations between ConAC in soils or rivers and wildfire history suggests that ConAC may be produced non-pyrogenically. Here, we show quantitative evidence that this occurs during the oxidation of biomass with environmentally ubiquitous hydroxyl radicals. Pine wood boards exposed to iron nails and natural weather conditions for 12 years yielded a …
