Engineering Commons^™

Targeted Products From Fast-Hydropyrolysis And Hydrodeoxygenation Of Biomass, Ian Tad Smith

Open Access Theses

Previously, the H2Bioil process was proposed as a possible way to convert sustainably available intact biomass into liquid fuels. The optimization of this process and possible synergies with other biomass conversion processes are presented in this thesis.

The selectivity of the PtMo hydrodeoxygenation catalyst was tuned using two different hydrogen partial pressures: 25 bar, and 2.5 bar. This effect was studied on cellulose and intact biomass samples to determine the effect that hydrogen has upon the retention of aromatic compounds found in intact biomass. These experiments show that it is possible for the hydrogenation activity of the PtMo catalyst to …

Thermodynamic Analysis Of Phenylpropanoid Pathway In Arabidopsis Thanliana, Patrick J. Ioerger, Rohit Jaini, John A. Morgan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biofuels represent a renewable alternative to traditional fossil fuels. As dependence on fossil fuels rise so does the importance of improving the production of alternative fuels. Lignin poses one obstacle in the development of such alternative fuels. Its presence strengthens cell walls and hinders degradation of polysaccharides into monosaccharides, increasing cost and time while decreasing efficiency of the process. Lignin is composed of three monolignols, each of which is produced through the Phenylpropanoid pathway; a series of chemical reactions. This work aims to determine which reactions in the pathway are least thermodynamically favorable and thus most limiting. From metabolic mapping …

Analysis Of The Fabrication Conditions In Organic Field-Effect Transistors, Rachel M. Rahn, Yan Zhao, Jianguo Mei

The Summer Undergraduate Research Fellowship (SURF) Symposium

Polymer-based organic field-effect transistors have raised substantial awareness because they enable low-cost, solution processing techniques, and have the potential to be implemented in flexible, disposable organic electronic devices. The performance of these devices is highly dependent on the processing conditions, as well as the intrinsic properties of the polymer. Processing conditions play an important role in semiconductor film formation and device performance. These factors may provide an important link between structure and performance. In this study, an empirical analysis tool, Process Scout, was applied to assess processing factors such as polymer concentration and silicon modification. This sanctioned the creation of …

Development Of A Parallel Multiphase Lattice-Boltzmann Solver To Study Stokes Number Effects On Particle Trajectories, Lenan Zhang, Anand Samuel Jebakumar, John Abraham

The Summer Undergraduate Research Fellowship (SURF) Symposium

Particle-laden flows are important owing to their relevance to many engineering devices such as coal combustors, gasifiers and solar thermochemical reactors. In a recent experimental study by Lau and Nathan [1], it was found that particles in a turbulent pipe flow tend to migrate preferentially depending on their Stokes number (St). Particles with a high St (>10) are concentrated near the axis while those with low St (

Optimal Surfactant Selection For Chemical Enhanced Oil Recovery In Low Temperature, Low Salinity, High Hardness Reservoirs, Christian D. White, Ryan A. Mulvenna, Rituraj Borgohain, Cliff Johnston, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Based on the environmental properties of a crude oil reservoir, only 20-30 % of oil product can be recovered using primary and secondary extraction methods. The remaining stranded oil can only be recovered via various enhanced oil recovery methods. Chemical enhanced oil recovery (EOR) uses specialty chemicals to extract trapped oil in rock layers by generating in-situ microemulsion in the presence of reservoir brine and oil. In this case study, phase behavior tests are conducted for microemulsion formation between the surfactant solution and the oil. The phase behavior tests model reservoirs with low temperature and low salinity. In order to …

Determining Glucose Isomerization Mechanisms On Lewis Acidic Beta Zeolites Using Isotropic Tracer Studies And 1h Nmr, Jacklyn N. Hall, Michael J. Cordon, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biofuels synthesized from biomass sources are becoming necessary for sustainable production due to their significantly lower net CO₂ production than fuels synthesized from fossil-based carbon sources such as petroleum. Catalytic pathways for the primary biomass-to-biofuels reaction pathway include the isomerization of glucose to fructose, which can be catalyzed by either Lewis acids or bases. Isolated metal atoms and metal oxide particles on Beta zeolites serve as active sites that catalyze this reaction through a Lewis acid 1,2-intramolecular hydride shift or by a Lewis base proton transfer mechanism, respectively. The Lewis acid mechanism has proven to have higher fructose selectivity …

Mechanical Dispersion Of A Semi-Solid Binder In A Wet Granulation Process, Justin W. Perry, James D. Litster, Nathan J. Davis

The Summer Undergraduate Research Fellowship (SURF) Symposium

High viscosity surfactant pastes have recently gained popularity in the production of high efficiency laundry detergents due to their ability to increase surfactant loading in granules. When using high viscosity semi-solid binders a unique challenge is presented because it forces granules to be formed primarily by mechanical dispersion; a relatively poorly understood process. Developing mechanistic models of this process will enhance knowledge of mechanical dispersion processes and improve process development for granules produced using this method. Experiments to determine the effect of three process parameters; paste temperature, impeller RPM, and time were carried out in a lab-scale granulator. Binder temperature …

Dissolution Of Chalcogens In Amine Thiol Solvents For Use In Nanoparticles, Gaurav A. Mittal, Caleb K. Miskin, Rakesh Agrawal

The Summer Undergraduate Research Fellowship (SURF) Symposium

Lead chalcogenide quantum dots have been shown to be ideal materials for solar cells due to their tunable band gap. Developing a dissolution procedure for chalcogens will help lower the production cost of the solar cells produced by the associated nanoparticles. Dissolution was performed in both aqueous and nonaqueous solutions. Precursors for sulfur and selnium were dissolved in both the aqueous solution of ammonium thioglycolate and ammonium hydroxide and in combinations of amines and thiols. Precursors for tellurium were dissolved in ethylenediamine and different thiols. Lead telluride forms larger microparticles that can be suitable for thermoelectric devices. The optimum solutions …

Adsorption Mechanisms Of Palladium On The Tobacco Mosaic Virus Surface, Gloriia D. Novikova, Oluwamayowa Adigun, Erin Retzlaff-Roberts, Michael T. Harris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Organic-inorganic materials synthesis using biological templates has recently drawn immense attention of researchers. Biotemplating has shown to be an efficient and economic means of nanomaterials production. Naturally stable, readily available and genetically malleable, Tobacco Mosaic Virus (TMV) is one of the most extensively studied and characterized biotemplates. Particularly, templated synthesis using TMV has produced high quality nanorods and nanowires that have been applied to batteries, memory devices and catalysis. The fundamental mechanisms, governing the adsorption of palladium on the TMV Wild Type and genetically modified versions (TMV1Cys and TMV2Cys), are not fully understood; this knowledge, however, is essential for future …

Development Of A Novel Enzymatic Pre-Treatment For Lignocellulosic Biomass, Melissa Robins, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biofuels, fuels derived directly from living matter, present a renewable and environmentally friendly alternative to petroleum based fuels. Bioethanol produced from low input energy crops or agricultural waste is a promising fuel source because it does not interfere with the human food supply chain and the ethanol produced can be blended with gasoline. These potential sources of bioethanol are not yet commercially viable due to a polymer called lignin present in the plant’s cell wall which impedes the conversion of cellulose to glucose and the eventual fermentation of glucose to ethanol. Developing new methods for the pretreatment of lignocellulosic biomass …

Processing Methods And Storage Conditions On Chocolate And Coffee Powder Flow Properties, Sunland L. Gong, Andrea Della Bella, Teresa M. Carvajal

The Summer Undergraduate Research Fellowship (SURF) Symposium

Powders are widely used in a countless number of industries, and are crucial to the quality control of products in areas such as pharmaceuticals and food. Particle physicochemical properties (morphology, solid state – crystalline, amorphous or both) are important factors for powder flow, which in turn can have significant impact on the stability, performance, and presentation of powders. Different processing methods as well as storage conditions such as relative humidity (RH) can drastically affect powder flow. Due to the widespread use of chocolate and coffee powder around the world, and their importance to the food industry, this work investigates two …

The Identification Of Optimal Pathways In Synechocystis Sp. Pcc 6803 By Flux Balance Analysis, Ning Xuan Yip, John A. Morgan, Longyun Guo

The Summer Undergraduate Research Fellowship (SURF) Symposium

Cyanobacteria are microorganisms considered advantageous for producing valuable compounds because of their high growth rates compared to plants. They also can be grown at large scale in photobioreactors. This research aims to use metabolic engineering strategies to maximize the phenylalanine yield in Synechocystis sp. PCC 6803. Our hypothesis is flux balance analysis will give different flux distributions with different objective functions. The scope of the project is modeling photoautotrophic metabolism of cyanobacteria with a genome scale stoichiometric model, testing several alternative objective functions. We also examined the tradeoff between growth and L-phenylalanine production with flux balance analysis. A linear programming …

Molecular Precursors In Aqueous Solution For Cigse Solar Cells, Bethany L. Mcilrath, Rakesh Agrawal, Mark J. Koeper

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thin film solar cells are one of the most promising alternatives to traditional silicon based solar cells. Copper, indium, gallium, and sufur/selenium (CIGS) act as the absorber layer in one type of thin films. CIGS films are preferable to silicon because they can have wider applications, such as flexible solar cells. The highest efficiency CIGS solar cells have been made using either expensive vacuum equipment or highly toxic chemicals. This study investigates non-toxic molecular precursor solutions deposited by spray coating. Stoichiometric amounts of CIGS are dissolved in ammonium thioglycolate and ammonium hydroxide to create the molecular precursor solution. This solution …

Oil Recovery In Low Temperature And Salinity Reservoir Rock Using Anionic And Anionic/Cationic Surfactant Formulations, Alec D. Bokhart, Ryan Mulvenna, Bryan Boudouris, Rituraj Borgohain, Cliff Johnston

The Summer Undergraduate Research Fellowship (SURF) Symposium

As oil reserves are being depleted in the United States, there is an increasing need to recover the trapped oil in the reservoir rock which accounts for up to 60% of the total oil available. This oil may be recovered using chemical enhanced oil recovery (EOR) techniques. In our case study, we investigated viable EOR surfactant/polymer formulations for conditions conducive to high efficiency oil recovery in ultra-low salinity, low temperature, and high hardness reservoirs. Formulations were screened for Winsor Phase I (microemulsions) or Winsor Phase III (bicontinuous emulsions),: both of which are conducive to high efficiency oil recovery. Strong emulsion …

Synthesis, Characterization, And Thermoelectric Properties Of Radical Siloxanes, Arnold J. Eng, Bryan Boudouris, Edward P. Tomlinson, Martha Emily Hay

The Summer Undergraduate Research Fellowship (SURF) Symposium

More than half of the annual energy consumption in the United States is lost as waste heat. Polymer-based thermoelectric devices have the potential to utilize this waste heat both sustainably and cost-effectively. Although conjugated polymers currently dominate research in organic thermoelectrics, the potential of using polymers with radical pendant groups have yet to be realized. These polymers have been found to be as conductive as pristine (i.e., not doped) poly(3-hexylthiophene) (P3HT), a commonly-used charge-transporting conjugated polymer. This could yield promising avenues for thermoelectric material design as radical polymers are more synthetically tunable and are hypothesized to have a high Seebeck …

A Novel Synthetic Yeast For Enzymatic Biodigester Pretreatment, Tianyu Tan, Mark S. Aronson, Arren Liu, Jill H. Osterhus, Melissa Robins, Suraj Mohan, Erich Leazer, Bowman Clark, Alexa Petrucciani, Katherine Lowery, James Welch, Casey Martin, Helena Lysandrou, Michael E. Scharf, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Lignin, a complex organic polymer, is a major roadblock to the efficiency of biofuel conversion as it both physically blocks carbohydrate substrates and poisons biomass degrading enzymes, even if broken down to monomer units. A pretreatment process is often applied to separate the lignin from biomass prior to biofuel conversion. However, contemporary methods of pretreatment require large amounts of energy, which may be economically uncompelling or unfeasible. Taking inspiration from several genes that have been isolated from termites and fungi which translate to enzymes that degrade lignin, we want to establish a novel “enzymatic pretreatment” system where microbes secrete these …

Carbon Dioxide Sequestration To Form Calcium Carbonate Nanoparticles, Krista E. Stump, Michael T. Harris

The Summer Undergraduate Research Fellowship (SURF) Symposium

The emission of carbon dioxide caused by burning fossil fuels is one of the leading sources of global warming. Reducing the amount of CO₂ released into the atmosphere through carbon sequestration can mitigate this problem. One method of carbon sequestration is the use of a carbon dioxide scrubber. Once captured, CO₂ can be used to create a valuable chemical commodity such as calcium carbonate nanoparticles. To create CaCO₃ particles in the 50-100 nanometer range, a chemical additive is necessary to limit particle size. The study used a laboratory scale carbon dioxide scrubber to react CO₂ with …

Platinum-Bismuth Bimetallic Catalysts: Synthesis, Characterization And Applications, Jose A. Saucedo Jr, Yang Xiao, Arvind Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Bimetallic catalysts have been explored and shown to exhibit unique characteristics which are not present in monometallic catalysts. Platinum is well known as an effective catalyst for oxidation and reduction reactions, and it can be made more effective when bismuth is introduced as a promotor. Thus, the effectiveness of the Pt-Bi catalyst was demonstrated in prior work. What is not clear, however, is the mechanism behind the catalyst function; why addition of bismuth to platinum decreases deactivation and increases selectivity, and how effective would the Pt-Bi catalyst be in deoxygenation reactions? In this work, the effectiveness of different variations of …

Measuring The Effectiveness Of Photoresponsive Nanocomposite Coatings On Aircraft Windshields To Mitigate Laser Intensity, Ryan S. Phillips, Hubert K. Bilan, Zachary X. Widel, Randal J. Demik, Samantha J. Brain, Matthew Moy, Charles Crowder, Stanley L. Harriman, James T. O'Malley Iii, Joseph E. Burlas, Steven F. Emmert, Jason J. Keleher

Journal of Aviation Technology and Engineering

In 2004, pilots reported 46 laser illumination events to the Federal Aviation Administration (FAA), with the number increasing to approximately 3,600 in 2011. Since that time, the number of reported laser incidents has ranged from 3,500 to 4,000. Previous studies indicate the potential for flight crewmember distraction from bright laser light being introduced to the cockpit. Compositional variations of the photoresponsive nanocomposite coatings were applied to an aircraft windscreen using a modified liquid dispersion/heating curing process. The attenuating effects of the deposited films on laser light intensity were evaluated using an optical power meter and the resultant laser intensity data …

Mechanism And Kinetics Of Homogeneous Catalysis, Silei Xiong

Open Access Dissertations

A model-based approach using a diverse set of data including monomer consumption, evolution of molecular weight, and end-group analysis was employed to determine each of the reaction specific rate constants involved in 1-hexene polymerization process catalyzed by a family of group IV single-site catalysts. The primary set of elementary reaction steps included initiation, normal propagation, misinsertion, recovery from misinsertion, monomer independent and dependent chain transfer. Robust determination of kinetic constants and reaction mechanisms for a series of Group IV amine bis-phenolate complexes led to the development of several structure−activity relationships.^ For some of the catalysts of the bis-phenolate family the …

Effect Of Maleic Acid On The Selectivity Of Glucose And Fructose Dehydration And Degradation, Ximing Zhang

Open Access Dissertations

5-Hydroxymethyfurfural (HMF), a platform chemical can upgrade to a variety of fuels and polymers, can be manufactured from lignocellulose. This study focuses on the Lewis and Brønsted acid effect on hexose dehydration for HMF production. We report the positive effect of maleic acid, a dicarboxylic acid used as Brønsted acid, on the selectivity of hexose dehydration to 5-hydroxymethyfurfural (HMF), and subsequent hydrolysis to levulinic and formic acids. We also describe the kinetic analysis of a Lewis acid (AlCl ₃) alone and in combination with HCl or maleic acid to catalyze the isomerization of glucose to fructose, dehydration of fructose …

Experimental And Modeling Investigation Of Cellulose Nanocrystals Polymer Composite Fibers, Si Chen

Open Access Dissertations

Cellulose nanocrystals (CNCs) are a class of newly developed and sustainable nanomaterial derived from cellulose-based materials such as wood. There have been substantial research efforts to utilize these materials as reinforcing agents. However, in order to develop CNC nanocomposites with industrial applications, it is necessary to understand how addition of CNCs affect the properties of the polymer nanocomposite. In the present work, several approaches, experimental and theoretical, are presented in an effort to characterize and understand the effect of CNCs on the properties of polymer CNC fibers. ^ Two experimental methods were used to develop cellulose acetate (CA) and CNC …

Using Mixtures Of Fatty Acid Methyl Esters As Phase Change Materials For Concrete, Leah Christine Liston

Open Access Theses

Phase change materials (PCMs) are an effective way of storing/releasing thermal energy via phase transformations. Incorporating PCMs into concrete pavements at airports has been suggested as a means to reduce the accumulation of snow and ice on runways. This thesis reports on the development of two phase change materials composed of binary mixtures of fatty acid methyl esters (FAME) which provide a solid-liquid transition slightly above 0°C with a high enthalpy of fusion. Current findings of this study indicate that these mixtures have the necessary properties to be a high performance PCM with the potential to reduce the levels of …

Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer

Open Access Theses

The purpose of this research is to investigate the feasibility and advantageous outcomes of modeling a complicated non-linear hybrid dynamical process as an interconnected dynamical system for the purpose of solving a hybrid optimal control problem under the framework of nonlinear model predictive control. This work considers a hybrid model of the startup process of an evaporation system. In this evaporation system a liquid containing mixture of a non-volatile component A and volatile solvents B (water) and C (alcohol) is heated to evaporate the solvents and obtain component A at a higher concentration using a column that is temperature controlled …

Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder

Open Access Dissertations

We have investigated the simulation-based, steady-state optimization of a new type of crystallizer for the production of pharmaceuticals. The multi-segment, multi-addition plug-flow crystallizer (MSMA-PFC) offers better control over supersaturation in one dimension compared to a batch or stirred-tank crystallizer. Through use of a population balance framework, we have written the governing model equations of population balance and mass balance on the crystallizer segments. The solution of these equations was accomplished through either the method of moments or the finite volume method. The goal was to optimize the performance of the crystallizer with respect to certain quantities, such as maximizing the …

Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis

Open Access Dissertations

The Water-Gas Shift (WGS) reaction (CO + H₂O → CO₂ + H₂) is an important chemical process for industrial hydrogen production. The overall goal of this project is to use kinetic experiments and in situ characterization techniques in tandem, in order to derive structure-activity relationships for various catalytic systems. These relationships facilitate the rational catalyst design by identification of catalyst descriptors. In order to establish such relationships, various studies were undertaken, such as (i) effect of transition admetals on the WGS catalysis by molybdenum carbide (ii) effect of residual oxygen content on the performance of …

Kesterite Thin-Film Solar Cell Absorbers Derived Using Inhomogeneous Czts Nanoparticles, Wei-Chang D. Yang

Open Access Dissertations

My doctoral research focuses on understanding the structure-property-processing relationship of the kesterite materials to improve their device performance. It is recognized in both my own work and the recent literature that the structural and compositional integrities of CZTSSe are crucial to derive the solar cell grade kesterite thin-films. Analytical electron microscopy (AEM) allows me to demonstrate the structural and compositional inhomogeneity of the CZTS nanoparticles and CZTSSe thin-films at the nanoscale. For example, the observed forbidden reflections in TED patterns and FFT diffractograms corresponding to HRTEM images indicate that cation disorder leads to stacking faults in CZTS nanoparticles. Probe-corrected STEM …

Propane Dehydrogenation On Single Site Gallium On Silica Catalyst, Shankali U. Pradhan

Open Access Theses

Light alkane dehydrogenation is gaining increasing importance due to the discovery of shale gas. Gallium based catalysts such as Ga/HZSM-3 and Ga₂O₃ have been used to dehydrogenate propane to propylene. However, the exact nature of the active site for propane dehydrogenation on Gallium based catalysts is still debated in literature. This work is aimed at understanding the nature of active site in Ga/SiO₂ catalyst for propane dehydrogenation. The Ga/SiO₂ catalyst is active and selective for propane dehydrogenation reaction. It is shown that Ga ⁺³ site co-ordinated with four O atoms is the most active form …