Chemical Engineering Commons^™

Supercritical Pyrolysis Of Toluene, Khue Dang Nguyen

LSU Master's Theses

The development of future high-speed aircrafts will required the jet fuel to act as the primary engine coolant to absorb excess heat produced by the engine components. To aid in removing the excess heat and reducing the aircraft’s weight, future jet fuels used for high-speed aircrafts will act as both coolant and fuel; however, by exposing the fuels to temperatures and pressures above their critical point, they undergo pyrolysis to form larger and/or more abundant polycyclic aromatic hydrocarbons (PAH) and eventually carbonaceous solid deposits in the pre-combustion environment. The formation of solid deposits in the pre-combustion environment results in clogging …

Developing A Tool To Characterize The Ultradian Rhythm In Diploid Saccharomyces Cervisiae Using The Reporter Gene Green Fluorescent Protein, Imran Chiragh

LSU Master's Theses

Biological rhythms control many temporal behaviors of organism, such as the sleep cycle, hearts rhythms, seasonal animal migrations etc. Understanding these rhythms would provide insight into the temporal process of living organisms. Saccharomyces cerevisiae, a budding yeast, is an ideal model organism to study biological rhythms in eukaryotic cells because of its sequenced genome and discerned processes. By characterizing the biological rhythm in budding yeast, insight can be gained into more complex organisms. Previous studies have exhibited oscillatory behavior of oxygen consumption and determined that deletion of the GTS1 gene dissipates this rhythm. However, to further understand the specific behavior …

Numerical Studies Of Flow In Porous Media Using An Unstructured Approach, Nathan Matthew Lane

LSU Doctoral Dissertations

Flow and transport in porous media is relevant to many areas of engineering and science including groundwater hydrology and the recovery of oil and gas. Porous materials are characterized by the unique shape and connectivity of the internal void structures which give rise to a large range in macroscopic transport properties. Historically an inability to accurately describe the internal pore-structure has prevented detailed study of the role of pore structure on transport. In recent decades however, the combination of high resolution imaging technologies with computational modeling has seen the development of fundamental pore-scale techniques for studying flow in porous media. …

Simulation Study Of Sweep Improvement In Heavy Oil Co2 Floods, Venu Gopal Rao Nagineni

LSU Master's Theses

Enhanced oil recovery by CO2 injection is a common application used for light oil reservoirs since CO2 is relatively easily miscible with light oils. CO2 flooding in heavy oil reservoirs is often uneconomic due to unfavorable mobility ratios. Reservoir heterogeneity further complicates the process as CO2 channels through high permeability layers leading to premature breakthrough. However, this can be controlled by choosing a suitable modification to the CO2 injection process enabling better sweep efficiencies, and making the process economic. The current work focuses on two such methods; water-alternating-gas injection (WAG) and profile modification by blocking gas flow in the high …

Catalytic Process For The Conversion Of Synthesis Gas To Ethanol For Use As An Alternative Fuel, Nitin Kumar

LSU Doctoral Dissertations

Higher alcohols are increasing as a proportion of the transportation fuel market, and can be used as neat fuels, or as blends with conventional fuels. For a number of reasons, these C2+-alcohols will be of interest in the foreseeable future. Large-scale production of higher alcohols will likely be carried out via syngas, which can be produced from a number of feedstocks, including coal, natural gas and biomass. Rhodium-based catalysts have been found to be the most active/selective for higher alcohols. However, the literature shows that the yields of C2+-alcohols that can be achieved with current catalysts, even the most active/selective, …

Surface Functionalization Of Crystalline Silicon Substrates, Sri Sai Vegunta

LSU Doctoral Dissertations

In this work, various chemical and electrochemical methods were demonstrated to attach application-specific organic monolayers to crystalline silicon substrates. In one study, alkyl monolayers were anodically electrografted or thermally grafted onto planar (100) silicon substrates using Grignard precursors. The results show electrografted methyl monolayers provide a stable Si-C termination, resisting oxidation on (100) surfaces for approximately 55 days in air. The alkyl termination could provide a potential alternative to defective native oxides and kinetically unstable hydride surfaces. A mechanism involving two electron transfers per grafting event was established for both the thermal and electrochemical routes. In another study, unsaturated organic …

Characterization Of Foam Flow In Pipes Using Two Flow Regime Concept, Rahul Narayanrao Gajbhiye

LSU Doctoral Dissertations

The objective of this study is to investigate the characteristics of foam flow behavior in pipes in a wide range of experimental conditions, including two pipe materials (stainless steel and nylon pipes with about 0.36 - 0.38 inch in inner diameter and 12 ft in length), three surfactant formulations (Cedepal FA-406, Stepanform-1050, and Aquet-944), and three surfactant concentrations (0.1, 0.5, and 5 wt%). The concept of “two foam-flow regimes”, consisting of high-quality regime and low-quality regime, is at the heart of interpreting the experimental data. The experimental results in horizontal pipes showed the presence of two distinct high-quality and low-quality …

Dry Reforming Of Methane On Rhodium And Nickel Substituted Pyrochlore Catalysts, Sarthak Gaur

LSU Master's Theses

Dry reforming of methane (DRM) has been widely investigated, with most studies showing rapid deactivation due to carbon deposition. This suggests a need to develop catalysts that limit carbon formation while avoiding structural changes at the elevated temperatures typical of this reaction. Here, we report CO2 reforming of methane on four pyrochlore catalysts. First, Rh was partially substituted for Zr in lanthanum zirconate (La2Zr2O7) to give La2Zr2-xRhxO7.5 (LRZ, x=0.112, 2 wt% Rh) pyrochlore. A second pyrochlore catalyst was synthesized in which Ca was further substituted into the La-site to give La1.95Ca0.05Zr2-xRhxO7 (LCRZ, x=0.055, 1 wt% Rh). A third catalyst was …

Studies Related To Coulombic Fissions Of Charged Droplets And Hygroscopic Behavior Of Mixed Particles, Harry Cook Hunter Iii

University of Kentucky Doctoral Dissertations

This dissertation describes two independent studies related to charged aerosols. The first study examines the role of electrical conductivity on the amounts of charge and mass emitted during the break-up of charged droplets via Coulombic fission. The second study examines the hygroscopic behavior of mixed particles. The results from both studies are presented here in detail along with an in-depth discussion of pertinent literature and applications in modern technologies.

Charged droplets break-up via a process termed Coulombic fission when their charge density reaches a certain level during which they emit a portion of their charge and mass in the form …

Solution Phase And Membrane Immobilized Iron-Based Free Radical Reactions: Fundamentals And Applications For Water Treatment, Scott Romak Lewis

University of Kentucky Doctoral Dissertations

Membrane-based separation processes have been used extensively for drinking water purification, wastewater treatment, and numerous other applications. Reactive membranes synthesized through functionalization of the membrane pores offer enhanced reactivity due to increased surface area at the polymer-solution interface and low diffusion limitations. Oxidative techniques utilizing free radicals have proven effective for both the destruction of toxic organics and non-environmental applications. Most previous work focuses on reactions in the homogeneous phase; however, the immobilization of reactants in membrane pores offers several advantages. The use of polyanions immobilized in a membrane or chelates in solution prevents ferric hydroxide precipitation at near-neutral pH, …

Studies On Silicon Nmr Characterization And Kinetic Modeling Of The Structural Evolution Of Siloxane-Based Materials And Their Applications In Drug Delivery And Adsorption, Jyotrhirmai Ambati

University of Kentucky Doctoral Dissertations

This dissertation presents studies of the synthetic processes and applications of siloxane-based materials. Kinetic investigations of bridged organoalkoxysilanes that are precursors to organic-inorganic hybrid polysilsesquioxanes are a primary focus. Quick gelation despite extensive cyclization is found during the polymerization of bridged silane precursors except for silanes with certain short bridges. This work is an attempt to characterize and understand some of the distinct features of bridged silanes using experimental characterization, kinetic modeling and simulation. In addition to this, the dissertation shows how the properties of siloxane- materials can be engineered for drug delivery and adsorption.

The phase behavior of polymerizing …

Synthesis And Energy Applications Of Oriented Metal Oxide Nanoporous Films, Qingliu Wu

University of Kentucky Doctoral Dissertations

This dissertation mainly addresses the synthesis of well-ordered mesoporous titania thin films by dip coating with PEO-PPO-PEO triblock copolymer surfactant template P123. Because P123 is composed of poly(ethylene oxide) [PEO] and poly(propylene oxide) [PPO] blocks, concentrations of ingredients are adjusted to tune the films’ wall thickness, pore size and mesophase. Structural changes are consistent with partitioning of species among PEO blocks, PPO blocks, and the PEO/PPO interface. Titanates localize near PEO and increase wall thickness (by 5 nm to 7 nm). Depending on aging temperature, PPG either swells the PPO cores (when it is hydrophobic) or introduces large (>200 …

Catalytic Hydrogenation Of Co To Higher Alcohols, Nachal Devi Subramanian

LSU Doctoral Dissertations

The interest in converting synthesis gas to alcohols and oxygenated fuel additives via CO hydrogenation is growing rapidly due to the increasing rise in oil prices. Among the potential end products, ethanol is desirable since it serves as a clean alternative fuel, a gasoline blend, and a hydrogen carrier to supply fuel cells. The high cost and limited availability of the most active/selective Rh-based catalysts has led to the development of base metal catalysts such as modified Cu-based catalysts. Literature suggests that a combination of Co (or Mn) with Cu can facilitate higher alcohol formation by a non-dissociative adsorption of …

Investigation Of An Iron-Based Additive On Coal Pyrolysis And Char Oxidation At High Heating Rates, John M. Sowa, Thomas H. Fletcher

Faculty Publications

Iron-based catalysts have been shown to enhance coal pyrolysis and char oxidation at low to moderate temperatures and heating rates (b1250 K and 1–1000 K/s). Such catalytic activity has not been demonstrated at high heating rates and temperatures approaching pulverized coal combustion applications. The effect of an iron-based additive on coal pyrolysis and char combustion was studied in a flat-flame burner system at high particle heating rates using a Kentucky bituminous coal. Pyrolysis and char reactivity of two treated coals with different catalyst loadings were studied and compared with the untreated coal. The total volatiles yield for the treated coals …

The Effects Of Wind On The Flame Characteristics Of Individual Leaves, Wesley J. Cole, Mckaye H. Dennis, Thomas H. Fletcher, David R. Weise

Faculty Publications

Individual cuttings from five shrub species were burned over a flat-flame burner under wind conditions of 0.75–2.80m s^-1. Both live and dead cuttings were used. These included single leaves from broadleaf species as well as 3 to 5 cm-long branches from coniferous and small broadleaf species. Flame angles and flame lengths were determined by semi-automated measurements of video images. Additional data, such as times and temperatures corresponding to ignition, maximum flame height and burnout were determined using video and infrared images. Flame angles correlated linearly with wind velocity. They also correlated with the Froude number when either the …

Investigation Of Solid-State Shear Pulverization Processing Parameters For Polyethylene-Clay Nanocomposites , Ben Aldrich

Honors Theses

Investigates multiple processing parameters, includingpolymer type, filler type, processing technique, severity of SSSP (Solid-state shear pulverization)processing, and postprocessing, of SSSP. HDPE and LLDPE polymers with pristine clay and organo-clay samples are explored. Effects on crystallization, high-temperature behavior, mechanicalproperties, and gas barrier properties are examined. Thermal, mechanical, and morphological characterization is conducted to determine polymer/filler compatibility and superior processing methods for the polymer-clay nanocomposites.

Shale Gas Rock Characterization And 3d Submicron Pore Network Reconstruction, Malek Elgmati

Masters Theses

"Determining shale gas petrophysical properties is the cornerstone to any reservoir-management practice. Hitherto, conventional core analyses are inadequate to attain the petrophysical properties of shale gas at submicron-scale. This study combines interdisciplinary techniques from material science, petrophysics, and geochemistry to characterize different shale gas samples from North America including Utica, Haynesville and Fayetteville shale gas plays. Submicron pore structure, clay mineralogy, wettability and organic matter maturation were investigated to evaluate the petrophysical properties of shale gas rocks and to determine the impact of organic and inorganic matters on wettability alteration for different fracturing fluids on shale gas rocks.

High pressure …

Effects Of A Nickel Reactor Liner And Other Reaction Variables During Supercritical Water Reformation Of Glycerin, Michael S. Stever

Masters Theses

"The non-catalytic reformation of glycerin using supercritical water was conducted in a 400-mL tubular reactor constructed of Haynesʼ Alloy 230. The evaluated parameters for this thesis include water-to-glycerin molar ratios ranging from 3 to 24 and reactor temperatures ranging from 500⁰C to 700⁰C. In addition, experiments were performed using the Haynes' Alloy 230 reactor both without a liner and with a Nickel 201 liner. Space time was maintained at approximately 100 seconds and the reactor pressure was kept constant at 24.1 MPa. The resultant effect on product gas composition and carbon gasification was determined. The product gases consisted of a …

Numerical Simulation Of Relative Permeability Modifier Effect On Oil And Water Production, Murad Mohammedahmed Abdulfarraj

Masters Theses

"Excess water production is one of the most prevalent operational problems that oil companies are facing. Polymers and polymer gels have been used widely to control excess water production for mature oilfields. It is well known that polymers/gels can reduce the permeability to water (Krw) much more than that to oil (Kro). This phenomenon is called disproportionate permeability reduction (DPR) and the polymers or gels that exhibit this behavior are called relative permeability modifier (RPM). When RPMs are placed in reservoir, reduced permeability to water can lead to decreased water production, and sometimes increased hydrocarbon production, therefore prolonging the useful …

New Catalysts For The Photocatalytic Reduction Of Carbon Dioxide To C1 Organic Compounds, Anna Hailey

Honors Theses

Photocatalytic reduction of carbon dioxide (CO2) has recently been identified as one of the five notable research areas in catalysis because it simultaneously reduces carbon emissions while storing clean, green solar energy in organic compounds. The development of efficient photocatalysts that take advantage of solar radiation is therefore an important area of research. Titanium dioxide (TiO2) is a commonly-used photocatalyst for this reaction, but it requires ultraviolet (UV) radiation to excite its electrons. Carbon-doping (C-doping) has been shown to reduce the intensity of energy required, thus allowing the photocatalyst to take advantage of the visible light spectrum. Copper (Cu), added …