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Full-Text Articles in Catalysis and Reaction Engineering

Functionalized Loblolly Pine Derived Ultraporous Activated Hydrochars For Efficient Carbon Capture, Swarna Saha Aug 2026

Functionalized Loblolly Pine Derived Ultraporous Activated Hydrochars For Efficient Carbon Capture, Swarna Saha

Theses and Dissertations

The increasing concentration of anthropogenic carbon dioxide (CO₂) emissions has intensified the demand for efficient and sustainable carbon capture technologies. This dissertation investigates the development of functionalized ultraporous activated hydrochars derived from loblolly pine through hydrothermal carbonization (HTC) followed by chemical activation for enhanced CO₂ capture applications. Different functionalization strategies, including deep eutectic solvent (DES) modification, zeolite-assisted HTC, palladium-assisted HTC, and CO₂-assisted HTC, were systematically explored to evaluate the influence of pore structure, surface chemistry, and adsorption energetics on CO₂ capture performance. The synthesized materials were characterized using BET, FTIR, XRD, TGA, SEM, and adsorption isotherm modeling to establish the …


Techno-Economic Assessment And Life Cycle Analysis Of Electrocatalytic Reduction Of Co2 To Ethanol., Omotolani Elizabeth Oduyebo May 2026

Techno-Economic Assessment And Life Cycle Analysis Of Electrocatalytic Reduction Of Co2 To Ethanol., Omotolani Elizabeth Oduyebo

LSU Master's Theses

This study presents a techno-economic analysis (TEA) and life cycle assessment (LCA) of the electrocatalytic reduction of CO₂ to ethanol, a multi-carbon (C2) product with significant market value. Prior TEA studies have relied on simplified lump-sum separation cost estimates, and prior LCA studies have rarely examined the combined effect of CO₂ source and electricity supply on carbon intensity gaps that this work addresses through process-simulation-grounded analysis. An Aspen Plus process simulation was developed for an anion-exchange membrane (AEM) electrolyzer system coupled with an extractive distillation separation train using ethylene glycol as the entrainer, achieving 99.9 wt.% ethanol purity …


Applications For The Quasi-Atomic Orbital And Constrained Density Functional Theory Methods On Catalytic Reactions, Alvaro David Loaiza Orduz Jan 2026

Applications For The Quasi-Atomic Orbital And Constrained Density Functional Theory Methods On Catalytic Reactions, Alvaro David Loaiza Orduz

LSU Doctoral Dissertations

Selective activation of C–O, C–H, and C–C bonds underpins biomass upgrading, alkane functionalization, and CO₂ conversion. Despite their importance, the electronic factors governing catalytic performance remain incompletely understood, and many industrial processes still rely on empirical trends or material-specific observations. This dissertation addresses this gap by applying density functional theory (DFT), thermodynamic decomposition, and electronic-structure analysis to identify unifying principles of reactivity across transition-metal phosphides, vanadate oxides, copper-based electrocatalysts, and mixed IrO₂–RuO₂ layers. This work examines how charge transfer, orbital localization, and ligand-induced perturbations control reaction pathways in diverse catalytic systems. C–O bond scission in 2-methyltetrahydrofuran (MTHF) and methanol was …


Elucidating Structure–Reactivity Relationships In Ni-Catalyzed Co2 Methanation, Majed Alam Abir Jan 2026

Elucidating Structure–Reactivity Relationships In Ni-Catalyzed Co2 Methanation, Majed Alam Abir

Graduate Theses, Dissertations, and Problem Reports (ETD)

The catalytic hydrogenation of carbon dioxide (CO2) to methane represents a promising strategy for carbon utilization and renewable energy storage within power-to-gas systems. When coupled with hydrogen derived from renewable electricity, CO2 methanation enables the conversion of intermittent energy sources into storable and transportable chemical fuels compatible with existing natural gas infrastructure. Nickel-based catalysts have emerged as leading candidates for this reaction due to their high activity towards CO2 methanation, abundance, and cost. However, the performance and long-term stability of Ni catalysts are strongly influenced by catalyst support properties, Ni nanoparticle size, and promoter effect, and …


Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran Jan 2026

Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran

Electronic Theses & Dissertations (2024 - present)

Anion exchange membrane water electrolysis (AEMWE) presents a promising pathway toward cost-effective and sustainable hydrogen production by integrating the chemical robustness of alkaline systems with the compact, zero-gap design of proton exchange membrane electrolyzers. However, the widespread implementation of AEMWE is limited by the availability of highly active and durable platinum-group-metal (PGM)-free catalysts and by an incomplete understanding of their degradation behavior under realistic operating conditions.

This dissertation focuses on the development, characterization, and mechanistic investigation of nanostructured MoNi4–MoO2-based electrodes for efficient and stable hydrogen generation under alkaline and membrane-integrated environments. MoNi4–MoO2 nanorods …


Material Degradation And Analysis Of N-Doped Graphene/Mof Nanocatalysts For Orr In Electrochemical Energy Systems, Niladri Talukder Dec 2025

Material Degradation And Analysis Of N-Doped Graphene/Mof Nanocatalysts For Orr In Electrochemical Energy Systems, Niladri Talukder

Dissertations

The development of advanced electrochemical energy conversion and storage systems is crucial for achieving sustainable energy security. As alternatives to precious metal-based catalysts in electrochemical systems, especially for the oxygen reduction reaction (ORR), Nitrogen-doped Graphene with Metal-organic Frameworks (N-G/MOF) nanocatalysts have shown exceptional promise in recent years. This research advances the understanding of N-G/MOF nanocatalysts by systematically examining their structural features, degradation traits, correlated performance losses, and other aspects related to catalytic activities.

First, nitrogen-doped graphene (N-G) nanocatalysts were thoroughly investigated, resolving their physical properties, the influence of synthesis parameters, molecular-level material structures, and chemical and electronic structural details of …


Cultivation Of Botryococcus Braunii For The Production Of Hydrocarbons Suitable For Fuel Use, Bryan C. Carroll Aug 2025

Cultivation Of Botryococcus Braunii For The Production Of Hydrocarbons Suitable For Fuel Use, Bryan C. Carroll

All Theses

Energy security, rural poverty, and climate change are pressing issues of our time. Biofuels provide a solution to these issues, with a focus on sustainable aviation fuel, SAF, due to compatibility with aircraft infrastructure and energy density. This research aims to review and produce knowledge about a specific microalga, Botryococcus braunii, for its potential for SAF. First a literature review on the process was conducted followed by an experimental study on the impact of aqueous media and inorganic carbon its growth and hydrocarbon content. The literature review found the process consists of cultivation followed by lipid extraction or hydrothermal …


Anion Exchange Membrane Transport And Accelerated Testing Methods For Co2 Electrolyzers With Cu-Based Electrocatalyst, John C. Hendershot Jul 2025

Anion Exchange Membrane Transport And Accelerated Testing Methods For Co2 Electrolyzers With Cu-Based Electrocatalyst, John C. Hendershot

LSU Doctoral Dissertations

Electrocatalytic carbon dioxide (CO2) reduction to C2+ products holds promise for low carbon intensity fuels, chemicals, and food; however, durability challenges, particularly bicarbonate (HCO3-)and carbonate (CO32-) salt precipitation, hinder their commercialization. This report considers water (H2O) and ion transport properties of conventional anion exchange membranes (AEMs) in zero-gap membrane electrode assembly (MEA) configurations using Cu electrocatalysts. Transport characterization includes H2O diffusion, permeability, potassium (K+) diffusion, and transference numbers using three commercial AEMs, including piperidinium-based (Versogen), quaternary ammonium-based (Fumasep), and imidazolium-based (Dioxide Materials) membranes. Accelerated lifetime …


Pd-Based Hydrogen Separation Membranes Synthesized Via A Liquid-Phase Route, Chase W. Thompson Jul 2025

Pd-Based Hydrogen Separation Membranes Synthesized Via A Liquid-Phase Route, Chase W. Thompson

Chemical and Biological Engineering ETDs

Palladium (Pd) membranes have gained significant attention for their ability to selectively separate hydrogen, a critical process for clean energy applications such as fuel cells and hydrogen storage. However, challenges such as grain growth, sintering, hydrogen embrittlement, and film uniformity limit their scalability and long-term stability. This thesis focuses on the controlled synthesis, deposition, and stability of Pd nanoparticles to optimize membrane performance for hydrogen separation. This work investigates solution-phase synthesis of Pd nanoparticles, focusing on temperature, precursor concentration, and solvent composition as key variables influencing particle growth and dispersion. Pd membranes were fabricated using nanoparticle deposition onto porous supports, …


Low Temperature Methane Coupling With Co And Co2, A K M Kazi F.M. Aurnob Jul 2025

Low Temperature Methane Coupling With Co And Co2, A K M Kazi F.M. Aurnob

LSU Doctoral Dissertations

Methane is the smallest hydrocarbon and the most abundant component in natural gas. Despite its availability, its chemical utilization has remained limited due to the challenges associated with direct methane activation and conversion. Most of the methane oxidation and oxidative carbonylation reactions in literature have been carried out at high-pressure using batch reactors or at ambient pressure using flow reactors. While batch reactors have been shown to have higher product yields, they are limited in their capability to provide real-time kinetic insights and comprehensive mechanistic understanding of the reactions involved due to the long residence time. This limits rationalization of …


Anion Exchange Membrane Durability For Electrochemical Co2 Reduction In Membrane Electrode Assembly Cells, Soundarzo Tasnim Jul 2025

Anion Exchange Membrane Durability For Electrochemical Co2 Reduction In Membrane Electrode Assembly Cells, Soundarzo Tasnim

LSU Master's Theses

The electrochemical reduction of CO₂ using membrane electrode assembly (MEA) cells has emerged as a promising approach for carbon capture and conversion into valuable products. This study investigates the degradation mechanisms of anion exchange membranes (AEMs) in CO₂ reduction applications, focusing on Sustainion X37-50, PiperION, and FAA-3-50. The research analyzes the impact of chemical and mechanical degradation on membrane performance, highlighting key stability challenges in long-term operation. Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS) were employed to monitor functional group stability and ionic conductivity loss over extended operation. The results indicate that hydroxide-induced degradation leads to nucleophilic …


Chemical Recycling Of Pet Plastic Waste, Charlie Parker, Benjamin Puga, Jake Verschoor Jun 2025

Chemical Recycling Of Pet Plastic Waste, Charlie Parker, Benjamin Puga, Jake Verschoor

Materials Engineering

The growing accumulation of plastic waste, specifically polyethylene terephthalate (PET), has driven the need for more efficient and scalable chemical recycling methods. This study investigated the methanolysis of PET using zinc oxide (ZnO) nanoparticles as a catalyst and tetrabutylammonium chloride (NBu₄Cl) as an ionic liquid, aiming to reduce methanol consumption while achieving high PET conversion efficiency. ZnO nanoparticles were synthesized via wet chemistry and characterized using Dynamic Light Scattering (DLS), which showed an average particle size of 13.5 nm with a polydispersity index of 0.1556, indicating a moderately-high monodisperse distribution of particles sufficient for reactions. The main conversion product, dimethyl …


Effect Of Household Oil Contamination And Agricultural Soil Contamination On Phyllosilicate Nanocatalyst Performance During Pyrolysis Of Polyolefins, Joey Velasquez Jun 2025

Effect Of Household Oil Contamination And Agricultural Soil Contamination On Phyllosilicate Nanocatalyst Performance During Pyrolysis Of Polyolefins, Joey Velasquez

Master's Theses

The effect of household oil and agricultural soil contamination on catalyst performance during polyolefin pyrolysis was simulated on mixed virgin plastic pellets by evaluating contamination influence on mixed plastic degradation temperatures. Three phyllosilicate nanocatalysts including Fulcat435, Fulcat22F and Y-Zeolite were evaluated in this work based on a literature review of catalyzed plastic pyrolysis and these catalysts’ ability to lower plastic decomposition temperature by 50 °C – 100 °C. These findings were confirmed in this research through thermogravimetric analysis of a polyolefin mixture and further developed in furnace experiments containing household oil and agricultural contamination. Household oil contamination deactivated each of …


Interaction Of Liquid Phase Diisopropyl Methyl Phosphonate (Dimp) With Material Surrogates For Components Of Soil And Combustion Products Of Metal Fuels, Khushi Sunil Patel May 2025

Interaction Of Liquid Phase Diisopropyl Methyl Phosphonate (Dimp) With Material Surrogates For Components Of Soil And Combustion Products Of Metal Fuels, Khushi Sunil Patel

Theses

Combustion products of three different Al-based materials, Al-CaCO3, Al-SiO2, and Al-Fe2O3 , have been produced to understand their interaction with liquid diisopropyl methyl phosphonate (DIMP), a surrogate for chemical weapon agents. The purpose of this is to see which materials were more effective at DIMP adsorption and decomposition at different temperatures. Prepared materials were characterized using electron microscopy, x-ray powder diffraction, and nitrogen adsorption. Prepared powders were submerged in DIMP and heated in a thermal analyzer, tracking the mass changes as a function of temperature. Surfaces of the recovered materials were studied using …


Zn–Assisted Synthesis Of M (Mn/Fe/Co/Ni)-N-C Catalysts For Multifunctional Electrochemical Activity, Kemila A. Chaudhary May 2025

Zn–Assisted Synthesis Of M (Mn/Fe/Co/Ni)-N-C Catalysts For Multifunctional Electrochemical Activity, Kemila A. Chaudhary

Electronic Theses & Dissertations

The design and development of atomically dispersed M-N-C catalysts (metal (M) supported on an nitrogen-carbon (NC) matrix with high multifunctional electrocatalytic performance is desirable but proved to be very challenging. Herein, we synthesized M-N-C catalysts (M = Fe, Co, Mn, and Ni) using Zn-assisted high temperature treatment and characterized using various techniques. The prepared catalysts were tested for their electrocatalytic performance towards oxygen and hydrogen evolution reaction (OER and HER) as well as oxygen reduction reaction (ORR) in alkaline media. The results indicated that Mn-N-C catalyst showed higher performance towards both the ORR (E1/2 = 0.90 V) and …


Ultrafast Laser Surface Structuring For Wettability Control On Copper, Akshay Arvind Nagvenkar May 2025

Ultrafast Laser Surface Structuring For Wettability Control On Copper, Akshay Arvind Nagvenkar

All Theses

Wettability is a crucial surface property influencing various phenomena, including heat transfer, cell adhesion, and corrosion. Engineering devices can achieve superior performance by precisely manipulating surface wettability. As a result, extensive research has focused on developing surfaces that exhibit either extreme water attraction (superhydrophilic) or strong water repellency (superhydrophobic). Tailoring surface wettability paves the way for numerous applications, such as drag reduction in marine vessels, controlled drug delivery, efficient water collection, advanced liquid transport systems, oil-water separation, anti-corrosion coatings, friction reduction, and self-cleaning materials. Ultrafast laser surface structuring is a promising approach for engineering multifunctional surfaces, effectively modifying material properties …


The Effect Of Catalyst Choice On Biodiesel Yield And Quality Using Waste Cooking Oil As A Feedstock, Neka Long May 2025

The Effect Of Catalyst Choice On Biodiesel Yield And Quality Using Waste Cooking Oil As A Feedstock, Neka Long

Honors Theses

Biodiesel is one current area of interest as a replacement for traditional diesel fuel. Benefits of biodiesel include that it can be derived from renewable resources, and it possesses properties similar to that of traditional diesel fuel. Biodiesel is often produced through a catalyzed transesterification process, which involves the use of a catalyst to aid in the conversion of triglycerides into alkyl esters. A method called the transesterification double step process (TDSP) was researched and used in this project due to the success seen using this method for the conversion of waste cooking oil to biodiesel. In this project, four …


Mg And Fe Co-Doped Perovskites For The Electrochemical Oxidative Coupling Of Methane In Solid Oxide Electrolyzers, Luke H. Denoyer Mar 2025

Mg And Fe Co-Doped Perovskites For The Electrochemical Oxidative Coupling Of Methane In Solid Oxide Electrolyzers, Luke H. Denoyer

Chemical and Biological Engineering ETDs

More efficient usage of shale gas reserves and natural gas resources will allow for higher olefin yields and lower greenhouse gas emissions. The oxidative coupling of methane (OCM) is a direct pathway for converting methane to ethylene at temperatures >700 °C. The OCM process is typically regulated via the choice of catalyst, reactor conditions, temperature range and gas mixing. The electrochemical oxidative coupling of methane (E-OCM) is a modification to the OCM reaction by controlling the oxygen content via externally applied potentials to an SOEC. Perovskite oxide catalysts are useful for E-OCM due to their flexible bond networks and desired …


Sustainable Aviation Fuel Production From Plastic Waste On Bifunctional Catalysts, Kamryn Culp Jan 2025

Sustainable Aviation Fuel Production From Plastic Waste On Bifunctional Catalysts, Kamryn Culp

Williams Honors College, Honors Research Projects

Catalytic hydrocracking was studied as a chemical recycling method for converting mixed plastic polypropylene (PP) and polyvinyl chloride (PVC) waste into sustainable aviation fuel-range hydrocarbons. Addressing both plastic pollution and aviation-related CO₂ emissions, bifunctional Ni- and Pt-based catalysts supported on Al₂O₃ and TiO₂ were evaluated under 30 bar hydrogen pressure at 250 °C. The inclusion of PVC, often regarded as a catalyst poison due to chlorine content, was examined at 1 wt% and 5 wt% to assess catalyst tolerance to it and resulted performance. Reaction rates and product selectivity were analyzed using gas chromatography. Results show that Ni/TiO₂ outperformed other …


Valorization Of Biomass Derivatives To Monomers By M-Mox Catalytic Hydrogenation & Hydrodeoxygenation, William Steere, Samir Castilla-Acevedo, Ben Auer, John Styers, Alan Allgeier Jan 2025

Valorization Of Biomass Derivatives To Monomers By M-Mox Catalytic Hydrogenation & Hydrodeoxygenation, William Steere, Samir Castilla-Acevedo, Ben Auer, John Styers, Alan Allgeier

UNH URC Open (2026 and after)

With increasing concern regarding global warming contributions by fossil fuels in petrochemical production, the potential use of biomass-derived molecules to serve as a more eco-friendly feedstock has grown in popularity. Specifically, sebacic acid, a versatile chemical used to produce nylons, plasticizers, and lubricants, has the potential to be obtained from bio-renewable feedstocks and alleviate environmental drawbacks from fossil fuel petrochemical production. Our research validates the catalytic conversion of the biomass-derived 2,2’-bifuran 5,5’-dicarboxylate (BFDCM) to sebacic acid (SA), through M-MOx catalyzed hydrogenation and hydrodeoxygenation. Catalytic activity tests were conducted for four different Pd-supported catalysts (C, Al2O3, …


Modeling And Simulation Of A Process For Upcycling Of Low-Density Polyethylene Plastic Waste To Ethylene, Xiaoyan Wang Jan 2025

Modeling And Simulation Of A Process For Upcycling Of Low-Density Polyethylene Plastic Waste To Ethylene, Xiaoyan Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethylene is one of the most widely produced petrochemicals, with an estimated global output of 180 million metric tons in 2022. Approximately 82 million metric tons of ethylene are used annually for plastic production, primarily for polyethylene (PE), as well as polypropylene (PP) and polyvinyl chloride (PVC). The CO₂ emissions associated with PE production were approximately 14 million metric tons in 2022. Globally, an estimated 70 million metric tons of PE are produced and consumed each year, with the majority (~79%) ending up in landfills or the environment.

This project proposes a novel process in which waste low-density polyethylene (LDPE) …


Effects Of Polyolefin Types On Catalytic Hydrocracking, Kenneth Jackson Seeber Jan 2025

Effects Of Polyolefin Types On Catalytic Hydrocracking, Kenneth Jackson Seeber

Williams Honors College, Honors Research Projects

Plastic waste recycling has become an important conversation in the last couple of decades with pollution on the rise. One of the few ways to recycle plastics is by breaking these long-chained polymers down via catalytic processes. Due to many plastic products being a blend, it is imperative that any chosen catalyst that could be used for recycling should be able to handle different types of polymers. This paper discusses how tungsten carbide over silica (WxC/SiO2) catalyzes the degradation of a few selected polymers and polymer blends. From this research it was determined that Wx …


Polystyrene Plastic Waste As An Organic Hydrogen Carrier, Alaina Bachmann Jan 2025

Polystyrene Plastic Waste As An Organic Hydrogen Carrier, Alaina Bachmann

Williams Honors College, Honors Research Projects

The proposed research develops and studies catalytic chemical processes that enables using polystyrene (PS) plastic waste as solid “organic hydrogen carriers” (OHC). Demands for OHCs are driven by desire to alleviate climate change, by replacing carbon-based energy sources with hydrogen. However, hydrogen is highly flammable and difficult to store and transport so OHCs are needed to facilitate its transportation. Common OHCs are liquid petroleum chemicals with unsaturated chemical structures. They can be hydrogenated to store hydrogen and dehydronated to release hydrogen at desired application sites. The proposed research aims to investigate the following cycle: hydrogen storage by hydrogenation of PS …


Catalytic Deoxygenation Of Oleaginous Biomass To Renewable Diesel And Sustainable Aviation Fuel Via Decarboxylation/Decarbonylation, Chukwudalu Great Umenweke Jan 2025

Catalytic Deoxygenation Of Oleaginous Biomass To Renewable Diesel And Sustainable Aviation Fuel Via Decarboxylation/Decarbonylation, Chukwudalu Great Umenweke

Theses and Dissertations--Chemistry

Several technologies have been developed to produce hydrocarbon biofuels – renewable diesel (RD) and sustainable aviation fuel (SAF) – from fats, oils, and greases (FOG), with the hydroprocessing of esters and fatty acids (HEFA) representing one of the most mature pathways. In its current form, HEFA is mainly reliant on the hydrodeoxygenation (HDO) reaction, which has several drawbacks since HDO requires large amounts and pressures of hydrogen, feedstocks of high purity and cost, as well as problematic sulfided catalysts that risk contaminating the biofuel product with sulfur. A process based on decarboxylation/decarbonylation (deCOx) offers an attractive alternative to …


Engineering Nanomaterials From Phase-Change Biological Materials Reacting With Carbon Dioxide, Qingyang Li Jan 2025

Engineering Nanomaterials From Phase-Change Biological Materials Reacting With Carbon Dioxide, Qingyang Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

The current global situation concerning CO2 emissions is increasingly alarming, with rising concentrations of CO2 significantly worsening climate change and global warming. Atmospheric CO2 levels are now at their highest in millions of years, driving a host of catastrophic effects, including but not limited to extreme weather events, rising sea levels, ocean acidification, disrupted ecosystems, deteriorating air quality, respiratory health issues, heat-related illnesses, threats to food and water security, and escalating social and geopolitical tensions. To keep global warming to no more than 1.5°C higher than that of pre-industry – as called for in the Paris Agreement – emissions need …


Microwave-Assisted Reduction Of Critical Metal Oxides From E-Waste Mixture, Kurundu Shavinka Jayasekera Jan 2025

Microwave-Assisted Reduction Of Critical Metal Oxides From E-Waste Mixture, Kurundu Shavinka Jayasekera

Graduate Theses, Dissertations, and Problem Reports (ETD)

The efficient recovery of critical metals such as tantalum (Ta), manganese (Mn), gallium (Ga), and indium (In) from electronic waste (e-waste) is essential for resource sustainability and environmental protection. This research uses microwave-assisted treatment to investigate the carbothermal reduction of these four specific metals from their oxides in a simulated e-waste mixture, with carbon black serving as both a microwave coupling and reduction agent. Microwave processing is used specifically because it offers a rapid and energy-efficient alternative to conventional thermal methods, with the benefits of intrinsic heating and selective heating of materials. The first experiments centered on understanding the effects …


Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola Jan 2025

Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola

Graduate Theses, Dissertations, and Problem Reports (ETD)

There has been an ongoing trend toward cleaner fuels for more environmentally benign forms of energy generation. Recently, hydrogen has been identified as a clean fuel for energy generation. However, the most established, efficient, and widely utilized technique for producing hydrogen remains the steam methane reforming (SMR) in the presence of catalyst. Unlike other fossil fuels, utilizing methane from natural gas in an SMR process to produce hydrogen emits less, but yet a notable sum of carbon dioxide. Furthermore, the endothermic nature of SMR reactions imply that there is a high energy requirement to obtain a substantial amount of hydrogen …


Decomposition Of Diisopropyl Methylphosphonate (Dimp) Exposed To Elevated Temperatures And Combustion Products Of Reactive Materials, Elif Irem Senyurt Dec 2024

Decomposition Of Diisopropyl Methylphosphonate (Dimp) Exposed To Elevated Temperatures And Combustion Products Of Reactive Materials, Elif Irem Senyurt

Dissertations

The safe and efficient destruction of chemical weapon agents (CWAs) stockpiles remains a critical global challenge. Understanding the thermophysical properties, decomposition mechanisms, and interactions of CWAs with their environment is crucial for developing effective strategies to mitigate their threats. Diisopropyl methylphosphonate (DIMP) and Dimethyl methylphosphonate are commonly used nerve agent surrogates. This dissertation focuses on DIMP and DMMP, investigates their properties and behavior under conditions relevant to prompt defeat scenarios.

The thermophysical properties of DIMP and DMMP were experimentally characterized, including vapor-liquid surface tension (3-60 °C) and viscosities of neat and aqueous solutions. Results revealed significant non-ideal behavior in aqueous …


Predictive Modeling And Sustainability Assessment Of Hydrothermal Liquefaction Of Seaweeds: A Techno-Economic And Life Cycle Analysis Approach, Micheal O. Asama Dec 2024

Predictive Modeling And Sustainability Assessment Of Hydrothermal Liquefaction Of Seaweeds: A Techno-Economic And Life Cycle Analysis Approach, Micheal O. Asama

Mechanical Engineering Theses

This study presents comprehensive predictive models and an economic and environmental assessment of HTL for converting macroalgae into biofuels and valuable co-products. Predictive models were developed based on experimental kinetic data to simulate batch HTL of brown seaweed, capturing the yields of biocrude, gas, biochar, and water-soluble compounds as functions of key process variables, including temperature, time, pressure, and water-to-biomass ratio. Analysis of Variance (ANOVA) confirmed that temperature and residence time significantly affect biocrude yield, with an optimal yield of 23% achieved at 283°C, 200 bar, 54 minutes, and a 10:1 water-to-biomass ratio. The model’s predictive accuracy was validated with …


Nickel Electrocatalysts On Carbon Supports For The Hydrogen Evolution Reaction., Mohan Paudel Dec 2024

Nickel Electrocatalysts On Carbon Supports For The Hydrogen Evolution Reaction., Mohan Paudel

Electronic Theses and Dissertations

Hydrogen is an important energy storage alternative to fossil fuels due to its high energy density. Currently, most hydrogen is produced through petroleum feedstocks, which produce large amounts of carbon dioxide. However, a more eco-friendly method is the electrocatalytic splitting of water into hydrogen and oxygen. Efficient catalysts for the hydrogen evolution reaction (HER) are typically platinum group metals, which are rare and expensive. There is growing interest in developing HER electrocatalysts with earth-abundant metals for water electrolysis. Nickel, which lies in the same group in the periodic table as Pt and has similar chemical properties, is explored extensively for …