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Design And Optimization Of 2.5 Dimension Porous Media Micromodel For Nanosensor Flow Experiments, Saade Alexis Bou-Mikael

LSU Master's Theses

Micromodels are used to visualize and study pore-scale phenomena such as immiscible displacements in porous media, foam flow behavior, and CO2 flooding. The understanding gained from these experiments can be used to develop models to predict future behavior of the reservoir. Most micromodels are constructed using lithography techniques that are restricted to 2D patterns that require artificial generation or manipulation of images to develop connected micromodels. Characteristics innate to the original rock structure are often lost or skewed in developing micromodels that bear little resemblance to the original media. Alternative microfabrication techniques using a micromilling tool have allowed us to …

Structural And Dynamical Properties Of Liquid And Solid Phases Of Ionic Liquids Confined Inside Nanoporous Materials, Ramesh Singh

LSU Doctoral Dissertations

The purpose of this research is to investigate the physical properties of ionic liquids (ILs) confined inside nanopores of different materials and morphologies. We are interested to study the effect of pore material, morphology and addition of organic solvents on the properties of confined ILs. Understanding the behavior of ILs inside nanopores is relevant to potential applications of these systems in electrochemical double layer capacitors (EDLCs) and dye sensitized solar cells (DSSCs). Such a fundamental understanding is also crucial to optimize the synthesis of hard-templated 1D nanostructures (nanorods, nanotubes, nanowires) based on organic salts, which may be imparted properties (e.g., …

A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski

LSU Doctoral Dissertations

Crystallization is a widely used chemical engineering separation unit operation process. Since this technique can produce high purity products it is used for the industrial production of many chemical compounds, such as pharmaceuticals, agrochemicals, and fine chemicals. The production of these products is a multi-million dollar industry. Any methods to improve the production of these products would be highly valued. Thus, the main objective of this work is to target model-based optimal strategies for crystallization operations specifically targeting crystal size and crystal size distribution (CSD). In particular, take the knowledge gained and translate it into an economically and practically feasible …

Boron Composite Nanoparticles For Enhancement Of Bio-Fuel Combustion, Neng Wang

LSU Master's Theses

Bio-fuels such as ethanol are good candidates to replace fossil fuels, which are being depleted, and whose combustion is associated with net production of greenhouse gases and other environmental issues. However, bio-fuels have low energy densities and can be subject to incomplete combustion. Boron is a promising additive for bio-fuels in combustion applications. It can increase their overall heat release and reduce ignition temperature, because boron itself is among the highest energy density materials. In this study, different B/rare earth oxide and B/Fe composite nanoparticles were produced by simple mechanical milling. Also, a new low temperature milling method was developed …

A Review Of Offshore Blowouts And Spills To Determine Desirable Capabilities Of A Subsea Capping Stack, Louise Matilde Smith

LSU Master's Theses

The events surrounding the Deepwater Horizon disaster have changed the face of deepwater operations. In order to continue drilling in the Gulf of Mexico, the regulatory body, the Bureau of Safety and Environmental Enforcement (BSEE), has required that applications to conduct work in the Gulf of Mexico (GOM) include a plan to stop, capture, or contain any uncontrolled release of fluids. The capping and containment systems built and implemented by BP during the event are an excellent starting point for minimizing pollution from deepwater subsea blowouts, but the system has limitations. The industry recognizes these limits but is currently focused …

A Modeling, Optimization, And Analysis Framework For Designing Multi-Product Lignocellulosic Biorefineries, Paritosh Kumar Sharma

LSU Doctoral Dissertations

The objective of this research is to propose a methodology to develop modular decision analysis frameworks to design value chains for enterprises in the renewable fuels and chemicals sector. The decision support framework focuses on providing strategic decision support to startup and new product ventures. The tasks that are embedded in the framework include process and systems design, technology and product selection, forecasting cost and market variables, designing network capacities, and analysis of risks. The Decision support system (DSS) proposed is based on optimization modeling; systems design are carried out using integer programming with multiple sets of process and network …

Computer Simulations Of Faceted Nanoparticles And Carbon Nanotubes In Liquid Crystals, Shivkumar Shankar Bale

LSU Doctoral Dissertations

The purpose of this research is to investigate the use of liquid crystals (LCs) to manipulate and organize faceted nanoparticles and carbon nanotubes (CNTs). Computer simulations at different levels of detail are used to study these systems. Results from this project will be relevant for potential applications of these systems in displays, nanoscale electronics, electro-optical switches, and in the development of composites with unique mechanical, thermal and/or electronic properties. In this research, two independent but directly related projects were carried out. In the first part of the research, we investigated the torque that develops when faceted nanoparticles, namely cubes and …

A Novel Rna Extraction Method For Cyanobacteria, Zenghui Zhang

LSU Master's Theses

Research on production of polyhydroxyalkanoates (PHA) by microorganisms has captured attention over the last two decades, since PHA have similar properties as petroleum-based thermoplastics, yet are close to carbon neutral and made from renewable sources. Cyanobacteria are considered to be good PHA producers because of their simple nutrient requirements (mainly water, sunlight and CO2) and fast cell growth. However, knowledge of metabolisms behind PHA production by cyanobacteria is limited. Therefore, gene expression analysis of cyanobacteria is required to get a thorough understanding at the molecular level, and gene expression analysis requires the extraction of high quality RNA. Extracting high quality …

Applications Of Cfd Simulations On Microfluidic Systems For Nanoparticle Synthesis, Yuehao Li

LSU Master's Theses

Microfluidics has been extensively investigated as a unique platform to synthesize nanoparticles with desired properties, e.g., size and morphology. Compared to the conventional batch reactors, wet-chemical synthesis using continuous flow microfluidics provides better control over addition of reagents, heat and mass transfer, and reproducibility. Recently, millifluidics has emerged as an alternative since it offers similar control as microfluidics. With its dimensions scaled up to millimeter size, millifluidics saves fabrication efforts and potentially paves the way for industrial applications. Good designs and manipulations of microfluidic and millifluidic devices rely on solid understanding of fluid dynamics. Fluid flow plays an important role …

Synthesis, Characterization, And Testing Of Atomically-Precise Au Clusters Supported On Tio₂ For Co Oxidation, Sarthak Gaur

LSU Doctoral Dissertations

Supported Au catalysts have been studied extensively for CO oxidation. These catalysts are known to catalyze this reaction even at sub-ambient temperatures. While recent literature demonstrates catalytic activity of gold nanoparticles <2 nm, the next stage in fine tuning this catalysis process is to develop gold clusters prepared with atomic precision. Such atomically precise gold catalysts supported on TiO2 hitherto have not been investigated for CO oxidation. The main objective of this work is to synthesize atomically-precise Au38 clusters in a flask-based method using principles of wet chemistry, to characterize these clusters using various advanced spectroscopic techniques, and to test these clusters as potential catalytic materials for CO oxidation. Furthermore, we have tested TiO2-supported Au38 clusters and a commercially purchased Au/TiO2 catalyst for CO oxidation at 30 °C and 60 °C, and used DRIFTS as a probe spectroscopic technique to correlate kinetics with the mechanism occurring on the surface of both catalysts in order to device the mechanistic pathways for CO oxidation. The work reported in this dissertation is the first spectroscopic observation of the phenomena where sulfur may have beneficial effect on the catalytic activity of Au/TiO2 catalysts. Such an interesting observation where sulfur has beneficial effect on catalytic activity of Au/TiO2 catalysts has never been observed in the past. We have also synthesized and tested Fe3O4@Au core-shell nanoparticles supported on TiO2 for CO oxidation. We show for the first time that, core-shell type nanogold catalysts are better suited compared to pure gold nanoparticles for heterogeneous gas phase catalysis of CO oxidation. By conducting comprehensive experiments towards understanding CO oxidation catalysis using X-ray photoelectron spectroscopy, infrared spectroscopy, and temperature programmed reduction, we show that the enhanced catalytic activity is due to a combination of factors ranging from synergistic interaction between Au and Fe, complete removal of organic capping ligands and the presence of metallic gold (Au0) in the active catalyst.

Differential Gene Expression In A Louisiana Strain Of Microalgae, John Joseph Tate

LSU Master's Theses

Considerable interest in alternative energy has stimulated research in biofuels, particularly microalgal biofuels. In particular, strains of algae that accumulate lipids to be used for biofuels must be adapted to outdoor growth and resistant to invasive species. Differential gene expression in a Louisiana algae/cyanobacteria co-culture consisting of approximately 97% Chlorella vulgaris and 3% Leptolyngbya sp. possessing these traits was examined. Possible reasons for the enhanced growth of the co-culture relative to a Chlorella monoculture were reviewed, including cyanobacterial symbiosis and chemicals produced by cyanobacteria or bacteria that could influence the growth of Chlorella. The co-culture and Chlorella monoculture were cultivated …

Double-Bond Isomerization Of Long Chain Olefins, James Edward Bruno

LSU Master's Theses

Bruno, James Edward, B.S., Western Michigan University, 2010 Master of Science, Fall Commencement, 2012 Major: Chemical Engineering Double-Bond Isomerization of Long Chain Olefins Thesis directed by Professor Kerry Dooley Pages in thesis, 54. Words in Abstract, 349. ABSTRACT Alkenyl Succinic Anhydride (ASA) is commonly used in the paper industry as a sizing agent. ASA is produced by reacting maleic anhydride with long-chain internal olefins. Such olefins are only available with the double bond in the terminal position, so an isomerization step is necessary. The isomerization can be catalyzed using solid strong acid catalysts, such as those containing sulfonic acid groups. …

An Experimental Investigation Of The Role Of Small Hydrocarbons And Combustion-Generated Nanoparticles On The Formation And Growth Reactions Of Polycyclic Aromatic Hydrocarbons During The Pyrolysis Of A Model-Fuel And Hydrocarbon Gases, Nimesh Bharat Poddar

LSU Doctoral Dissertations

Polycyclic aromatic hydrocarbons (PAH) are an important class of environmental pollutants formed during fuel combustion or pyrolysis. Therefore, an experimental study has been undertaken to better understand the formation and growth pathways of PAH.

To investigate the efficacy of C₃ species as PAH growth agents in the context of solid fuels, pyrolysis experiments have been performed in an isothermal quartz flow reactor in the temperature range of 700–1000 °C and a fixed residence time of 0.3 s. Experiments are performed with the C₃ hydrocarbon, propyne; with catechol (ortho-dihydroxybenzene), a model-fuel representative of aromatic moieties in coal …

Measurement Of Interfacial Tension In Hydrocarbon/Water/Dispersant Systems At Deepwater Conditions, Mohamed Abdelrahim

LSU Master's Theses

The events of the Deepwater Horizon oil spill in the Gulf of Mexico were associated with great water depths that made it difficult to understand the behavior of the spilled oil as it came in contact with the seawater. The remedial subsea application of chemical dispersants draws interest to evaluate the interfacial interactions between the oil and water at such great water depths. Most importantly, a quantification of the interfacial tension (IFT) between the spilled oil and seawater at deepwater conditions can provide insight into the effectiveness of the chemical dispersion of spilled oil. In this study, Macondo crude oil …

Strategies For Real Time Reservoir Management, Yuanyuan Shuai

LSU Doctoral Dissertations

Real–time reservoir management is developed to manage a shrinking labor force and rising demand on energy supply. This dissertation seeks good strategies for real–time reservoir management. First, two simulator–independent optimization algorithms are investigated: ensemble–based optimization (EnOpt) and bound optimization by quadratic approximation (BOBYQA). Multiscale regularization is applied to both to find appropriate frequencies for well control adjustment. Second, two gathered EnKF methods are proposed to save computational cost and reduce sampling error: gathered EnKF with a fixed gather size and adaptively gathered EnKF. Finally, oil price uncertainty is forecasted and quantified with three price forecasting models: conventional forecasting, bootstrap forecasting …

Copper-Cobalt Catalysts For Conversion Of Syngas To Ethanol And Higher Alcohols, Miranda Louise Smith

LSU Doctoral Dissertations

Higher alcohols produced by catalytic conversion of synthesis gas are potential octane enhancers for transportation fuels. Copper-cobalt catalysts have emerged as alternatives to the ethanol-selective, but expensive, rhodium-based ones. The reducibility of the catalyst and the CO adsorption mode are important factors in directing the selectivity of CO hydrogenation toward methanol, hydrocarbons, or higher alcohols. In this study, Cu/SiO2, Co/SiO2, and bimetallic CuCo/SiO2 catalysts, as well as their tin-promoted analogues, were synthesized and characterized by TPR, in situ XRD, in situ XANES, and in situ DRIFTS. Cobalt addition to Cu/SiO2 created an amorphous fraction of CuO that was more easily …

Efficacy Of Multifunctionalized Saccharide Constructs For The Attenuation Of Amyloid-Beta Toxicity, Dhruva Dilip Dhavale

LSU Doctoral Dissertations

There is evidence that amyloid-beta (Aβ) toxicity is mediated through interactions and binding with neuronal surface sialic acids in Alzheimer’s disease (AD). The binding affinity is higher if the sialic acids are clustered and toxicity of Aβ was attenuated by removal of neuronal sialic acids. Thus, interfering with cell membrane-Aβ binding using biomimetics that could reproduce the clustered sialic acid structure could present us with a potential target for therapeutic intervention in AD. Based on this hypothesis, we developed several multifunctionalized sialic acid labeled chitosan compounds of different valency, or number of sialic acid per chitosan molecule, to attenuate Aβ …

Lipid Production From A Louisiana Native Chlorella Vulgaris/Leptolyngbya Sp. Co-Culture For Biofuel Applications, Rong Bai

LSU Doctoral Dissertations

Over the last several decades, microalgae have garnered great interest for biofuel production mainly due to the high lipid productivity and minimum land competition with food crops. In this research, a Louisiana native Chlorella vulgaris/Leptolyngbya sp. co-culture was selected for lipid production. The goal of this work is to improve the lipid productivity and lipid composition of this co-culture via optimizing irradiance and nitrogen levels, lipid extraction method and modeling of pilot photobioreactor (HISTAR). Effects of irradiance and nitrate nitrogen levels on total lipid yield, neutral lipid portion, and fatty acid profile of non-aerated and aerated co-cultures were investigated in …

Experimental Investigations In Co2 Sequestration And Shale Caprock Integrity, Abiola Olukola Olabode

LSU Master's Theses

More than sixty percent (60%) of conventional hydrocarbon reservoirs which are potential CO2 repositories are sealed by tight shale caprock. The geochemical reactivity of shale caprock during CO2 diffusive transport needs to be included in the reservoir characterization of potential CO2 sequestration sites as slow reactive transport processes can either strengthen or degrade seal integrity over the long term. Several simulation results had predicted that influx-induced mineral dissolution/precipitation reactions within shale caprocks can continuously reduce micro-fracture networks, while pressure and effective-stress transformation first rapidly increase then progressively constrict them. This experimental work applied specific analytical techniques in investigating changes in …

Experimental Study Of The Effect Of Drilling Fluid Contamination On The Integrity Of Cement-Formation Interface, Nnamdi Charles Agbasimalo

LSU Master's Theses

Well cementing is one of the key processes performed during drilling and completion of wells. The main objective of primary cementing is to provide zonal isolation. Failure of cement to provide zonal isolation can lead to contamination of fresh water aquifers, sustained casing pressure, or blowout. For effective cementing, the cement slurry should completely displace the drilling fluid. In practice, this is hard to achieve and some mud is left in the wellbore where it contaminates the cement after cement placement.

This study investigates the effect of mud contamination of cement on the integrity of cement-formation interface. Flow-through experiments were …

Risk Of Well Integrity Failure Due Sustained Casing Pressure, Koray Kinik

LSU Master's Theses

Sustained casing pressure (SCP) is considered a well integrity problem. The approach of this study is to look at SCP as environmental risk due hydrocarbon release. Currently, the risk is qualified by the value of surface pressure (Pcsg) that may cause failure of casing head. However, the resulting rate of gas emission to the atmosphere is not considered. Also not considered is a possibility of breaching the casing shoe due transmission of Pcsg downhole. The objective of this study is to develop methods for maximum possible air emission rates (MER) and risk of subsurface well integrity failure due SCP. Mathematical …

Effect Of Surfactants And Brine Salinity And Composition On Spreading, Wettability And Flow Behavior In Gas-Condensate Reservoirs, Yu Zheng

LSU Doctoral Dissertations

The well-known condensate blockage problem causes severe impairment of gas productivity as the flowing bottom-hole pressure falls below the dew point in gas-condensate reservoirs. Hence, this study attempts to investigate the concept of modifying the spreading coefficient and wettability using low-cost surfactants in the near wellbore region, to prevent the gas flow problems associated with condensate buildup. This study also examines the effect of brine salinity and composition on wettability, spreading and adhesion in condensate buildup regions, to evaluate the ability of brine salinity/composition for enhanced gas productivity in gas-condensate reservoirs. In this study, experiments were performed at both ambient …

An Experimental And Theoretical Critique Of Flow Model Accuracy, Shannon Ray Chollett

LSU Master's Theses

In today’s exploration and production environment it is required that engineers must collect and use vast amounts of data for flow model construction and calibra- tion, as well as reservoir estimation and optimization. With modern technology, the data volume can be overwhelming. It is necessary that data monitoring and calibration are highly efficient. It is also essential that physical and mathematical models can be tested in repeatable, inexpensive experiments. The experiments described in this thesis will develop and perform verification of algorithms and can generate prior geomodels, collect and process seismic refraction data, collect and process production data, and calibrate …

Simulations Of The Primary Cement Placement In Annular Geometries During Well Completion Using Computational Fluid Dynamics (Cfd), Muhammad Zulqarnain

LSU Master's Theses

Effective zonal isolation during primary cementing is only possible when drilling mud in the annulus is completely displaced with cement, while the spacers aid in this process. During the displacement process the rheological properties of fluids used and the operating conditions control the motion of different fluids interfaces; desired stable interfacial displacement leads to piston like motion. Computational Fluid Dynamics (CFD) tool with the Volume-of-Fluid (VOF) has been validated against experimental and used to conduct numerical experiments in a virtual well model consisting of 50 ft vertical section of 8.765" x 12.5" annulus having initially mud and this mud is …

Numerical Study Of Downhole Heat Exchanger Concept In Geothermal Energy Extraction From Saturated And Fractured Reservoirs, Yin Feng

LSU Doctoral Dissertations

Geothermal energy has gained a lot of attention recently due to several favorable aspects such as ubiquitously distributed, renewable, low emission resources while leveraging the advances in the associated technologies such as directional drilling and low enthalpy power generation plant. However, there are still many challenges such as the high initial capital cost of drilling and surface facilities, environmental risk of seismicity due to the induced disequilibrium in the formation, and sustainability of project over designed operational life. Traditional downhole heat exchangers (DHE) could potentially reduce the capital cost and the risk of seismicity, but they are unable to maintain …

Catalytic Oxidative Desulfurization: A Comparison Of Reactors, Andrew Marshall Madrid

LSU Master's Theses

A novel technology, a pulsed oscillating monolith reactor (POMR), was compared to a standard autoclave reactor for oxidative desulfurization (ODS) of a model diesel fuel. Two classes of catalysts, mesoporous Ti-MCM-41 and Pd on carbon, were used for ODS. The oxidants used were O2 and peroxide. The model diesel compound was 75 wt% alkanes, 24 wt% alkylaromatic, 0.95 wt% sulfur heterocycles and 0.05% nitrogen heterocycles. ODS reactions were conducted from 343-423 K and pressures from 1.0-1.3 MPa O2. The only component that was not oxidized was the alkane. The POMR showed promise; there was up to a factor of 20 …