Chemical Engineering Commons^™

Fundamental Studies Of Surfactant Templated Metal Oxide Materials Synthesis And Transformation For Adsorption And Energy Applications, Saikat Das

Theses and Dissertations--Chemical and Materials Engineering

This work addresses fundamental aspects of designing templates and curing conditions for the synthesis of mesoporous metal oxide thin films. The first section addresses selection of cationic-carbohydrate surfactant mixtures to synthesize templated silica thin films for selective adsorption of simple carbohydrates based on molecular imprinting. Nuclear magnetic resonance and fluorescence spectroscopy results suggest a novel structure for mixtures of alkyl glucopyranosides or xylopyranosides with cationic (trimethylammonium) surfactants. Despite thermodynamically favorable mixing, the carbohydrate headgroups in the mixed micelle adopt an inverted configuration with their headgroups in the micelle core, and therefore are inaccessible for molecular imprinting. This orientation occurs even …

Interfacial Engineering Of Biomass Hydrolysis By Cellulase Enzymes And Mechanistic Modeling Of Hydrolysis Of Cellulose Substrates, Ravinder Kumar Garlapalli

Theses and Dissertations--Chemical and Materials Engineering

Lignocellulosic biomass is a sustainable and renewable energy resource that can be converted to fuels and other commodity chemicals, but this conversion is currently limited by its recalcitrance to enzymatic degradation. Because of this recalcitrance, the major challenges in the commercialization of enzymatic hydrolysis processes are the relatively low hydrolysis rates, limited cellulose conversion under some conditions, and high cost of enzymes.

Enzymatic hydrolysis is influenced by the structure of the biomass after pretreatment and the mode of enzyme action, but has also been shown to be enhanced by surfactant additives. The objective of this work was to elucidate the …

Evaporation-Induced Formation Of Well-Ordered Surface Patterns On Polymer Films, Wei Sun

Theses and Dissertations--Chemical and Materials Engineering

Various techniques of fabricating surface patterns of small scales have been widely studied due to the potential applications of surface patterns in a variety of areas. It is a challenge to fabricate well-ordered surface area efficiently and economically. Evaporation-induced surface patterning is a promising approach to fabricate well-ordered surface patterns over a large area at low cost. In this study, the evaporation-induced surface patterns with controllable geometrical characteristics have been constructed. The dewetting kinetics on deformable substrate is also investigated.

Using simple templates to control the geometry and the evaporation behavior of a droplet of volatile solvent, various gradient surface …

Determining The Effects Of Cd151 And Β1 On Tumor Cell Adhesion And Migration, Rachel R. Essex

Theses and Dissertations--Chemical and Materials Engineering

Previous studies have shown that the upregulation of CD151 and β₁ is associated with poor prognosis in many cancers such as breast cancer. Studies have provided evidence that these proteins are associated with the adhesion and migration of tumor cells. In this study, a microfluidic flow chamber was utilized to determine how CD151 and β₁ affected the firm and initial adhesion of metastatic breast cancer cells to a planar endothelial monolayer under shear stress. This system mimicked the adhesion of metastatic breast cancer cells to the endothelial cells of the circulatory system. CD151 and β₁ increased the …

Delivery Of A Fatty Acid Signal Via Rtil For Biofilm Dispersion, Rachaud M. Keyes

Honors Theses

A number of proposed applications for ionic liquids involve ionic liquid/water interfaces, such as, chemical separations or drug delivery systems. Therefore, an understanding of the solubility and micellar behavior of ionic liquids in an aqueous environment is critical fundamental knowledge. The long term goal of our study was ionic liquids for delivery of biological active agents; therefore, we chose the anion, bis(trifluoromethanesulfonyl)imide (Tf2N) since it promotes water stability and forms water immiscible RTILs. The study then paired the Tf2N-anion with three different classes of cations. By adding apolar substituents (-CH2-) to the cation, the size of the molecule increases in …

Design And Synthesis Of Sigma-1 Probe For Positron Emission Tomography (Pet) Imaging, May Ly

Honors Theses

Sigma-1 receptor radioligands have the potential to detect and monitor various neurological diseases. Because sigma-1 receptors are believed to be associated with numerous psychiatric conditions and neurodegenerative diseases, radioligands for sigma-1 receptors have the potential to serve as novel diagnostic tools and may be useful in assessing treatment effectiveness. A benzothiazolone 18F-labeled sigma-1 receptor ligand, CM304, has demonstrated promise as a specific positron emission tomography radiotracer for visualizing sigma-1 receptors in living subjects. Based on CM304, backup molecules were created to improve the overall drug profile, including half- life and bioavailability.

Optimization Of A Chemical Production Facility: A Study Of Operating Conditions, Equipment Sizing, And Economics Of An Ethylbenzene Production Plant., Xi Peng

Honors Theses

Economics of a chemical plant depend on multiple factors: grade of a feed, types of catalyst, operating temperature and pressure, cost of equipment, and many other factors could have influences on economics of the plant. In a previous study about an ethylbenzene facility, our team scrutinize two proposed changes. An optimization plan is recommended by our team in order to maximize the net present value (NPV) of the plant. This report focuses on demonstrating rationales of setting certain operating conditions, showcasing the details of optimization, and elucidating the reasons behind applying these modifications. The team used simulating software PRO/-II to …

Optimization: A Perspective On Improving An Ethylbenzene Production Design, Derrick C. Marchant

Honors Theses

The goal of optimization in a chemical process or system involves improving an existing design or a combination of devices. In the case of an established process such as the ethylbenzene production process investigated here, the optimization involves improving an established process and choosing the best available case within a set of constraints that also considers maximizing the economic bottom line. An objective function must be selected for an optimization problem which defines the achievable goal. The objective function of the optimization process presented here is to minimize the estimated annual operating cost (EAOC). An EAOC takes in to account …

Optimization Of An Ethylbenzene Process, Garrison Padgett Morgan

Honors Theses

In industry, chemical plants should be running at optimal performance in order to maximize profit. However, this is frequently not the case. Optimization is the process of improving an existing situation, device, or, in the case of chemical engineers, a chemical process. Furthermore, there are numerous strategies to optimize a chemical process, and it is up to the engineer to decide what to change in order to make the optimization worthwhile. Last semester, I was able to show my knowledge of optimization by applying changes to an existing ethylbenzene producing plant. I simulated the base case for this plant and …

Application Of Discrete Element Method And Computational Fluid Dynamics To Selected Dispersed Phase Flow Problems, Oladapo Olanrewaju Ayeni

LSU Doctoral Dissertations

A parallel discrete particle modelling framework (PAR_DPM3D) is applied to study three fundamental multiphase flow problems: The sedimentation of a cluster of particles in a viscous ambient fluid, multiphase flow in a bench-scale fluidized bed and granular segregation and mixing dynamics in a rotating drum. Various phenomena including torus formation and particle cluster breakup are reproduced. We provide new insights into the volume fraction dependence of the dynamic characteristics of a settling particle cluster and find a similar dependence in the simulations as in the theoretical predictions of Nitsche and Batchelor 1. Similarities in the interaction between a system of …

A Comprehensive Optimization Framework For Designing Sustainable Renewable Energy Production Systems, Aryan Geraili Nejadfomeshi

LSU Doctoral Dissertations

As the world has recognized the importance of diversifying its energy resource portfolio away from fossil resources and more towards renewable resources such as biomass, there arises a need for developing strategies which can design renewable sustainable value chains that can be scaled up efficiently and provide tangible net environmental benefits from energy utilization. The objective of this research is to develop and implement a novel decision-making framework for the optimal design of renewable energy systems. The proposed optimization framework is based on a distributed, systematic approach which is composed of different layers including systems-based strategic optimization, detailed mechanistic modeling …

Deepwater Gulf Of Mexico Oil Spill Scenarios Development And Their Associated Risk Assessment, Muhammad Zulqarnain

LSU Doctoral Dissertations

World’s growing energy demand has pushed oil companies to explore and produce hydrocarbons in complex and technologically challenging deepwater environments. These difficult and complex operations involve the risk of major accidents as well, demonstrated by disasters such as the explosion and fire on the UK production platform Piper Alpha and capsizing of the Deepwater Horizon rig in the Gulf of Mexico (GoM). Accidents cause death, suffering, pollution of the environment, disruption of business and bad reputation to oil industry. A quantitative risk analysis technique has been used in this study to identify and categorize risk associated with different life phases …

Bioplastic Production In Cyanobacteria And Consensus Degenerate Pcr Probe Design, Courtney Edward Lane

LSU Doctoral Dissertations

Cyanobacteria show much promise in reducing biodegradable thermoplastic production costs; however, most currently characterized strains are ill-equipped to do so. The result of Objective I produced a high-throughput assay designed to discover existing cyanobacterial strains and rapidly characterize them as PHA-producers or potential PHA-producers. This assay will play an instrumental role in the attainment of a novel cyanobacteria environmental isolate capable of accumulating high levels of PHA naturally. Objective II produced an open source computer program which dramatically speeds the design of similar assays for any arbitrary genetic screening purpose. The program is not limited to this implementation alone. In …

Laboratory Experimental Demonstration Of The Effect Of Oceanic Whitecaps In The Transport Of Oil And Dispersant Components To The Atmosphere, Paria Avij

LSU Doctoral Dissertations

During the DWH oil spill, vast quantities of crude oil were released into the sea-surface environment of the Gulf of Mexico. There has been ample research focused on the transport of oil into the different environmental sections. Evaporation has been considered to be the only transport pathway of oil spill matter into the atmosphere. However, the aerosolization of oil and dispersant via bursting bubbles as they occur in whitecaps and breaking waves has not been considered in the oil and dispersant budget calculation. This transport vector is significant as it is the dominant source of particulate matter production in the …

Electrospinning Of S-B-S Triblock And S-I-S Triblock Copolymers For Use In Fuel Filtration, Kevin Houser

Williams Honors College, Honors Research Projects

The following research project looked into the potential of using nanofibers of syrene-isoprene-styrene triblock copolymer produced through the electrospinning process for the filtration of water out of fuel as well as a comparison of styrene-isoprene-styrene triblock to the styrene-butadiene-styrene triblock nanofibers produced at equivalent operating parameters. Based on the work completed, it is concluded that the styrene-isoprene-styrene triblock is not suitable for use in filtration with the current electrospinning conditions. On average, the styrene-isoprene-styrene triblock produced nanofibers of lower average diameter and lower standard deviation in diameter when compared to styene-butadiene-styrene triblock.

Formation Of Polymer Micro-Tubes, Daniel Peters

Williams Honors College, Honors Research Projects

Abstract

Current demand for organs is greater than the supply of donated organs, which means that a new method of obtaining replacement organs needs to be found. The objective of the research is to evaluate the use of thermo-triggered self-rolling polymer tubes that can be used for scaffolds in tissue engineering. Additionally, the research also includes a method for forming polymer tubes through the removal of a sugar fiber, coated with a thin film of polymer, by dissolving it in deionized water. For the first approach, the effect of the aqueous environment and temperature on a polymer bilayer was observed …

Determining The Critical Micelle Concentration Of Polymer Matrix For Drug Delivery Purposes, Katie Emmert

Williams Honors College, Honors Research Projects

Targeted oral release systems have been a large topic within drug delivery systems. There are several benefits to an oral delivery including patient convenience and lower chance of infection. The colon specifically has been researched as the release media. The colon is an ideal location for a release because the pH is stable with high levels of microorganisms. Like any type of drug delivery research, there are several hurdles to overcome. In order for a drug to be released in the colon, the drug must survive the stomach and be biocompatible. This biocompatibility and pH sensitivity was created using a …

The Impact Of Shrinkage Reducing Admixtures On The Corrosion Of Steel Rebar In Concrete, Carlee C. Mccowin, Donald P. Visco Jr.

Williams Honors College, Honors Research Projects

Chemical admixtures are prepared in modern concrete to control certain performance properties, such as strength, setting-time, and workability. In this research, the corrosion inhibition properties of various shrinkage reducing admixtures in a synthetic concrete pore solution are examined. These compounds can inhibit or promote corrosion of the carbon steel rebar in concrete structures. The corrosive effects were tested by modeling the environment of concrete in a cathodic cell with a similar pH (12-13). Each shrinkage-reducing admixture (SRA) was compared to a standard reference cell. Tafel curves were used to determine the corrosion current and potential.

New Multiphase Reactor Design Using Electrospun Nanofibers, Victoria Smith

Williams Honors College, Honors Research Projects

No abstract provided.

Biosurfactants In Electrospinning, Jonathan Russell

Williams Honors College, Honors Research Projects

Surfactants are useful in electrospinning to help improve the fiber morphology. Crocin is a naturally occurring biosurfactant from saffron that is highly soluble in water. By electrospinning a biocompatible polymer, such as polyethylene oxide (PEO) and Crocin, one can improve the fiber morphology. A systematic study of PEO was conducted by varying the voltage, flow rate, and gap distance. The viscosity of the solution was determined using a viscometer and the surface tension was determined using the pendant drop method. Fiber morphology was examined using SEM and fiber diameters were determined using ImageJ to measure the fibers in the SEM …

Temperature Control Of An Emulsion Polymerization Process, Evan M. Arnold

Williams Honors College, Honors Research Projects

The project premise was to create a new temperature control scheme for an emulsion polymerization process at the pilot scale with intentions of implementing the system into a production facility in the near future. The data was collected using electronic instrumentation at a current emulsion polymerization pilot plant facility in real-time and saved in a Microsoft Excel format. The control scheme was based on three parameters: the rate of change, temperature dead band around the set point to determine heating or cooling, and a jacket fluid clamp temperature. After research and experimentation on actual emulsion polymerization batches it was determined …

Ambit Of Multiphase Cfd In Modelling Transport Processes Related To Oil Spill Scenario And Microfluidics, Abhijit Rao

LSU Doctoral Dissertations

During the ‘Deepwater Horizon’ accident in the deep sea in 2010, about 4.9 million barrels of oil was released into the Gulf of Mexico, making the spill one of the worst ocean spills in recent times. To mitigate the ill effects of the event on the environment, subsea injection of dispersants was carried out. Dispersant addition lowers the interfacial tension at oil/water interface and presence of local turbulence enhances the droplet disintegration process. The oil droplets contain a plethora of hydrocarbons which are soluble in water. In deep spill scenarios, droplets spend large amounts of time in water column; hence, …

Analyses Of The Mec1 Dna Damage Pathway In Saccharomyces Cerevisiae, William Barrett Ainsworth

LSU Doctoral Dissertations

Eukaryotic organisms implement conserved surveillance machinery to sense and respond to DNA damage. Fundamental to the repair process is coordinated regulation of repair genes and initiation of cell cycle arrest protocols. Failure to preserve these checkpoints results in accumulation of mutated DNA and aberrant cell phenotypes that are characteristic of human disease. The yeast, Saccharomyces cerevisiae, utilizes the MEC1 checkpoint pathway to regulate the DNA damage response. This study addressed two overarching themes of transcriptional and post-translational regulation within the MEC1 pathway. We first applied our understanding of the MEC1 DNA damage transcriptional response to develop advanced luciferase whole cell …

Molecular Dynamics Simulation Of The Structure, Dynamics And Crystallization Of Ionic Liquids Under Confinement And Low Temperature, Xiaoxia He

LSU Doctoral Dissertations

Ionic liquids (ILs) have sparked widespread interest due to their peculiar properties and the resulting possibility of manifold applications. In this dissertation, molecular dynamics (MD) simulations have been used to elucidate the dynamics, structure and crystallization of ionic liquids in the bulk and confinement. First we studied the properties of the ILs [dmim+][Cl-] and [emim+][NTf2-] when they are confined inside nanomaterials such as CMK-3, CMK-5 and an isolated amorphous carbon nanopipe (ACNP). The results indicate that the ions of the ILs form different layers inside these nanomaterials and their dynamics are slower due to the confinement. We also found significant …

Electrochemical Study Of Ammonium Interaction With Au,Sn And Cu Electrodes In Nonaqueous Electrolytes, Guoying Qu

LSU Doctoral Dissertations

Nonaqueous electrolytes play an important role in electrochemical devices such as flip chip and lithium-air batteries. In this work, we examine ammonium-Cu, Sn and Li interactions in nonaqueous electrolytes to optimize the future flip chip flux and electrolyte additive of lithium-air battery. The activity of halogen-free carboxylic acid flux is considered one of the most important aspects in controlling flip chip joint quality recently. CuOx removal effectiveness of carboxylic acid solutions at Cu substrates using electrochemical methods at elevated temperatures from 100ºC to 180ºC is studied thoroughly by chronopotentiometry and gravimetric analysis. Carboxylic acid-based solutions with ethanolamine show oxide removal …

Multi-Platform Arabinoxylan Scaffolds As Potential Wound Dressing Materials, Donald C. Aduba Jr

Theses and Dissertations

Biopolymers are becoming more attractive as advanced wound dressings because of their naturally derived origin, abundance, low cost and high compatibility with the wound environment. Arabinoxylan (AX) is a class of polysaccharide polymers derived from cereal grains that are primarily used in food products and cosmetic additives. Its application as a wound dressing material has yet to be realized. In this two-pronged project, arabinoxylan ferulate (AXF) was fabricated into electrospun fibers and gel foams to be evaluated as platforms for wound dressing materials. In the first study, AXF was electrospun with varying amounts of gelatin. In the second study, AXF …

The Synthesis Of Solid Supported Palladium Nanoparticles: Effective Catalysts For Batch And Continuous Cross Coupling Reactions, Kendra W. Brinkley

Theses and Dissertations

Catalysis is one of the pillars of the chemical industry. While the use of catalyst is typically recognized in the automobile industry, their impact is more widespread as; catalysts are used in the synthesis of 80% of the US commercial chemicals. Despite the improved selectivity provided by catalyst, process inefficiencies still threaten the sustainability of a number of synthesis methods, especially in the pharmaceutical industry. Recyclable solid supported catalysts offer a unique opportunity to address these inefficiencies. Such systems coupled with continuous synthesis techniques, have the potential to significantly reduce the waste to desired product ratio (E-factor) of the production …

Measurements And Modeling Of Hydrocarbon Mixture Fluid Properties Under Extreme Temperature And Pressure Conditions, Babatunde A. Bamgbade

Theses and Dissertations

Knowledge of thermodynamic fluid properties, such as density and phase behavior, is important for the design, operation, and safety of several processes including drilling, extraction, transportation, and separation that are required in the petroleum. The knowledge is even more critical at extreme temperature and pressure conditions as the search for more crude oil reserves lead to harsher conditions. Currently, there is dearth of experimental data at these conditions and as such, the predictive capability of the existing modeling tools are unproven. The objective of this research is to develop a fundamental understanding of the impact of molecular architecture on fluid …

Polysaccharide-Based Shear Thinning Hydrogels For Three-Dimensional Cell Culture, Vasudha Surampudi

Theses and Dissertations

The recreation of the complicated tissue microenvironment is essential to reduce the gap between in vitro and in vivo research. Polysaccharide-based hydrogels form excellent scaffolds to allow for three-dimensional cell culture owing to the favorable properties such as capability to absorb large amount of water when immersed in biological fluids, ability to form “smart hydrogels” by being shear-thinning and thixotropic, and eliciting minimum immunological response from the host. In this study, the biodegradable shear-thinning polysaccharide, gellan-gum based hydrogel was investigated for the conditions and concentrations in which it can be applied for the adhesion, propagation and assembly of different mammalian …

Fabrication Of Tissue Precursors Induced By Shape-Changing Hydrogels, Olukemi O. Akintewe

USF Tampa Graduate Theses and Dissertations

Scaffold based tissue reconstruction inherently limits regenerative capacity due to inflammatory response and limited cell migration. In contrast, scaffold-free methods promise formation of functional tissues with both reduced adverse host reactions and enhanced integration. Cell-sheet engineering is a well-known bottom-up tissue engineering approach that allows the release of intact cell sheet from a temperature responsive polymer such as poly-N-isopropylacrylamide (pNIPAAm). pNIPAAm is an ideal template for culturing cell sheets because it undergoes a sharp volume-phase transition owing to the hydrophilic and hydrophobic interaction around its lower critical solution temperature (LCST) of 32°C, a temperature close to physiological temperature. Compared to …