2017 Slatt Scholars
Santiago Calderon Novoa
Study on the Catalytic Conversion of Methane and Carbon Dioxide into Hydrogen Gas using Ni-SiO2 Catalysts, and its Impact on the Energy Field
Department of Chemical and Biomolecular Engineering
Faculty Advisor: Eduardo Wolf
The project’s focus is to study how the conversion of methane into hydrogen can be catalysed using low-cost catalysts. The importance of said study lies in the novelty of using nickel catalysts supported by SiO2 and in the current global necessity of finding other ways to obtain fuels not reliant upon fossil fuel deposits. As the reaction being studied makes use of methane and carbon dioxide (two greenhouse gases) to produce a mixture of gases (syngas) that can later be synthesized to longer hydrocarbons, the outcomes of this study could have positive implications: the discovery and refining of a pathway that can produce long hydrocarbon fuels such as gasoline or diesel, and the production of organic compounds usable by the polymer industry and other industries. The major objectives of this research are: understanding how transition metal catalysts can be improved using SiO2 to increase their activity, investigating how side reactions can inhibit the activity of the catalyst and find ways to prevent the deactivation of the catalyst, estimating the impact on the energy industry the catalyst can have, and finding different ways to synthesize the catalyst that could lead to greater conversion of methane to hydrogen.
Santiago Calderon Novoa Final Report
Lukas Cepkauskas
Segmented Copolymers of Triptycene-containing Hydrophobic Oligomers for Increased Mechanical Stability and Proton Conduction
Department of Chemical and Biomolecular Engineering
Faculty Advisor: Ruilan Guo
Proton exchange membrane fuel cells (PEMFCs) serve as a promising and upcoming source of electrical energy. Vital to these fuel cells are the proton conducting membranes, which are composed of polymer electrolytes, or polyelectrolytes. For years, Nafion served as the industry standard, offering good conductivity, low swelling, and solid mechanical properties and chemical resistance. Problems arise when Nafion is exposed to low relative humilities (RH<50%) and high temperatures (T> 80 °C). Under these conditions, Nafion experiences poor conductivity, decreased mechanical properties, and high methanol permeability in direct methanol fuel cells (DMFCs). Multiblock copolymer membranes with alternating hydrophilic and hydrophobic sequences have emerged as very promising alternatives to replace Nafion® in PEMFCs. Recent work in the Guo Lab has shown that incorporating triptycene units into the hydrophobic block of multiblock copolymers led to significant increase in the dimensional stability of the membrane while maintaining the desired proton conductivity, largely due to the unique supramolecular interactions induced by triptycene units. This research attempts to extend these benefits into segmented copolymers with triptycene-containing hydrophobic block of fixed length via a one-pot synthesis. This new approach would greatly simplify the synthesis of triptycene-containing polyelectrolytes, and the resulting segmented copolymers are expected to exhibit excellent membrane properties comparable to those of multiblock copolymers, which are prepared via multiple steps. Specifically, the segmented polymers will follow the same procedure as the random copolymer, except I will first synthesize an oligomer composed of triptycene-hydroquinone and the unsulfonated monomer (DCDPS) with predetermined molecular weight. I will then combine the synthesized oligomer with biphenol and the sulfonated monomer (SDCDPS) to form the final triptycene-containing segmented copolymers. By doing so, I hope to control the structure of the final polymer more effectively. In particular, I will systematically vary the degree of sulfonation and the length of hydrophobic segment in order to study the effect of the membrane ionic content on the water uptake/swelling as well as proton conductivity and thermal stability of the resulting membranes.
Luis Fernandez
Mapping Wind Flows in Perdigão
Department of Aerospace and Mechanical Engineering
Faculty Advisor: Harindra Fernando
Perdigão, Portugal is a small town located in a little valley (Vale Cobrão) between two ridges with wind flowing transverse to the valley, giving rise to unique wind flows that vary with the time and temperature of day. Often, winds flows at high, steady speeds - making Perdigão appear to be a good candidate for wind power generation. A drawback to these wind flows is that they are highly turbulent, which imparts vibrations on the wind turbines and can wear out their gear boxes at a quicker rate than normal. This research project aims to study wind flows in Perdigão in order to better understand their behaviour at various times of day, which may lead to a better understanding of turbulent systems. With this better understanding, wind power installations will be able to maximize energy generation while at the same time mitigating wear-and-tear on the turbines.
Sheridan Foy
Gas Solubility of Nonvolatile Separation Solvents
Department of Chemical and Biomolecular Engineering
Faculty Advisor: Edward Maginn
This project intends to predict the solubility properties of ionic liquids as solvents in the gas separation process. Separations are an integral part of many manufacturing processes and account for the use of 4500 trillion Btu per year, or 22% of all American in-plant energy use. The most widely used forms of separation technology include distillation and evaporation, which also require the most energy due to the thermal requirements of their components. There is, therefore, a need to find nonvolatile separation solvents that can reduce the need for high-energy separation processes and ultimately decrease energy usage. Recently, ionic liquids have been especially interesting to the research community for industrial and commercial purposes. They are organic salts that are liquids at less than 100. They have no measureable vapor pressure, and in a distillation process, they require no thermal regeneration. As a solvent extraction material, they appear to be a low-energy solution for gas separations. This project will use a Monte Carlo molecular simulation package called Cassandra, which is developed by Professor Maginn’s research group, to compare simulated solubility data of ionic liquid and gas systems to experimental data. Once the ability to match experimental data is confirmed, solubility data of many different ionic liquid and gas mixtures can be predicted in order to determine which ionic liquids work best for different gas separations.
John Higham
Throughput and Permeability Effects of PT-Spraying High Performance Copolymer Membranes for Water Treatment Applications
Department of Chemical and Biomolecular Engineering
Faculty Advisors: William Phillip and David Go
If the increasing global demand for clean water at low energy costs is to be met, higher performance and more efficient separation membranes must be designed and implemented in both desalination and water treatment. Previous work has demonstrated the extraordinary promise of self-assembled, copolymer membranes as part of the solution to the impending water crisis. Poly(acrylonitrile-oligo(ethylene glycol) methyl ether methacrylate-glycidyl methacrylate)-coated [P(AN-OEGMA-AHPMA)-coated] membranes are of particular note because they have proven to be amenable to both surface and inner-pore functionalization. After reacting with sodium azide, the copolymer nanopores that form following self-assembly can be functionalized and tailored to adsorb a broad range of micropollutants and heavy metals like bisphenol-A (BPA), lead (Pb2+), copper (Cu2+), and cadmium (Cd2+). However, initial studies on such membranes reveal that even though they bind large amounts of contaminants selectively, the pore sizes within the copolymer assembly are too small such that the water permeability is significantly reduced. To resolve this issue, a novel method of forming the P(AN-OEGMA-AHPMA) membrane assembly has been proposed. A piezoelectric transformer (PT), a device that converts electrical energy to mechanical force and vice versa, can be employed to generate electric currents that split P(AN-OEGMA-AHPMA) into charged droplets. Gravitational forces then drive the droplets toward a membrane situated below the transformer. This results in a “spray” composed of beads of self-assembled, porous copolymer. As the co-polymer pores formed in the PT-spray are larger than the pores examined in previous studies, it is proposed that PT-sprayed membranes will have greater throughput while retaining high rates of heavy metal and micro-pollutant adsorption.
Elisabeth Kerns
Perovskite Halide Exchange for Better Solar Cells
Department of Chemistry and Biochemistry
Faculty Advisor: Prashant Kamat
The research project will focus on the theoretical basis of the physical chemistry behind solar cells. The analysis of the perovskite materials using spectroscopy will further the scientific understanding of the materials, giving the project a direct relationship to improving alternative energy. The research into the mechanism and effect of halide exchange in perovskites will provide insight that may later be used to develop better solar cell technologies.
Brady McLaughlin
[Re]-Evaluating the Cost of Electricity due to Death at Hospitals with Unreliable Energy Systems-VSL/E Metric
Department of Physics
Faculty Advisor: Abigail Mechtenberg
My research project for the summer of 2017 would be a practical and more rigorous escalation of my current research, which I have done since last spring semester, including this summer, on energy shortages in primary level health care facilities For this project, I will be going to Uganda to take practical measurements of load and supply data at such facilities- it will be the first time that we will be collecting data ourselves as opposed to utilizing data taken from other papers, as I have done. This research will serve to enable us to practically corroborate research already established in an article that Dr. Mechtenberg and I have written with Ugandan co-authors promoting a metric called the value of an electricity based statistical life (VSL/E). This metric is based on the value of a statistical life and an electrical capacity shortage of a healthcare facility that could lead to loss of life due to inability to diagnose or treat a patient, or from sudden loss of power that leads to lifesaving machines shutting off, or even lights in surgery rooms going off mid-surgery. We argue that the VSL/E should be used to properly adjust the limits on how much should be spent on an electrical system in a situation where lives depend on the availability of electricity. While I have done simulations and theoretical analysis to determine the VSL/E for certain healthcare systems in different countries, to further understand the argument and have real world examples that support the analysis that leads to it, I need to go to countries such as Uganda that are affected by an unreliable national grid. If we can prove that it is this will allow me to see how the actual readings deviate from the simulations, so that I can run analysis with less uncertainty in it. I would also work with medical and engineering professionals to develop appropriate backup systems that are also reliable and can assist in electricity supply when the main grid or generation source goes out, so that the critical loads are still being met. The implementation of such a backup system might require more time than this project would provide for, but could be an extension of the research, with at least the groundwork being laid over this summer. Another part of this research will be defining critical loads from an engineering and a medical perspective. Understanding what a critical load is will be instrumental in defining load prioritization algorithms so that critical loads are the first ones served and the last ones to fail when supply is not sufficient, ensuring that potential life loss is minimized.
Hannah Naguib
Synthesis of Hyperbranched Polymers with Post-Functionalization Specificity
Department of Chemistry and Biochemistry
Faculty Advisor: Haifeng Gao
The applications for this research project involve the use of synthesized hyperbranched copolymers in light-harvesting mechanisms. By subjecting an AB2 monomer system to substances such as coumarin 343 dye, Copper-Catalyzed Azide-Alkyne Cycloaddition Polymerization (CuAACP) can trigger the production of a core complex which serves as a strong interior for further functionalization. Subsequent layers gained through post-functionalization contribute to the polymer’s specificity concerning light harvesting and absorption. Additionally, the core itself exhibits light-harvesting properties due to the incorporation of coumarin into the complex. The effects of stoichiometric ratios of AB2 monomer in the polymerization reaction will be examined in order to infer the optimal ratio for the fastest polymerization kinetics with the highest conversion. Upon synthesizing these polymers, post-functionalization reactions will be carried out such that they would mimic the outer shell created around the light-harvesting core complexes aforementioned.
John Salvadore
Perdigão Wind Energy Field Study
Department of Aerospace and Mechanical Engineering
Faculty Advisor: Harindra Fernando
Field data will be collected from a single wind turbine located at Perdigão, Portugal, the wake and downstream flow of wind studied in order to develop a more accurate windfarm micromodel for the unique valley terrain in Perdigão, as well as to develop methodologies that could be broadly applied to more effectively design windfarm micromodels in the future. To that end, the project will emphasize optimal sensor placement in the field, and accurate multi-scale flow simulations that account for topographic and atmospheric variables in the lab. Ultimately, the goal of the project is to better understand the downstream impact of land based wind turbines, expedite construction, and improve the overall facility efficiency through the development of more accurate wind farm micromodels for complex valley terrain, as seen in Perdigão. The major foci of the project include: 1) studying multi-scale flow interactions, i.e. turbulence and mixing throughout the valley over time; 2) understanding the influence of terrain heterogeneity on flow development, expanding the valley model from two shear parallel walls to ridges with natural variability; 3) observing the thermal transitions and cycles in the valley, 4) understanding the influence of surface inhomogeneity, expanding the valley model from a flat surface to a varied slope; and 5) studying the wake and impact region of the flow after interacting with the turbine to identify influences it may have on the environment downstream. All of which will be investigated and answered in some capacity through proper instrumentation of the site, taking measurements of the flow velocity, temperature and turbulence, and photographic imaging of the surface and ridges, and IR imaging of thermal phenomenon.
Miles Wood
Empowering Ugandans to Power Uganda: Exploring the Social Return on Investment (SROI) of the Business of Energy in Uganda
Department of Applied and Computational Mathematics and Statistics
Faculty Advisor: Abigail Mechtenberg
I am exploring the social return on investment (SROI) of the energy of business in Uganda by developing, conducting, and observing a business incubator focused on encouraging organic development of locally-sourced, sustainable energy systems. Ugandan Energy-Business teams from Mountains of the Moon University (MMU), Makerere University (MU), Ugandan Martyrs University (UMU), and Ugandan Small Scale Industries Association (USSIA) will co-design and build at least three devices, ultimately constructing a mini-grid in a given community. My research will focus on the social return on investment (SROI) of an organically-catalyzed reversal of traditional energy generation trends. I am assessing the impact of reliable energy on local businesses, schools, and hospitals, as well as the impact of heightened capital circulation in the Ugandan economy. Tasks to accomplish this will include observation of the incubator, focusing on the decisions made by participants, and interviews with local community members in management of businesses, schools, and hospitals. This work is crucial to understand better the value of economic independence in an international development context.
Anthony Zappia
Plasmonic Enhancement of Solar-thermal Water Desalination in a Functionalized Au-SiO2 Shell-core Nanoparticle-loaded Porous Membrane
Department of Aerospace and Mechanical Engineering
Faculty Advisor: Tengfei Luo
This project seeks to combine surface functionalization of gold nanoparticles with heat-focusing properties of a porous substrate in order to develop a relatively low-cost, efficient and practical solar desalination technology. The main research objective is to develop a hybrid hydrophilic-hydrophobic porous membrane structure loaded with thiol functionalized Au-SiO2 shellcore nanoparticles for plasmonically-enhanced solarthermal water desalination. The hypothesis is that thiolation of the nanoparticles improves interfacial heat transfer through hydrogen bonding. This will be accomplished by capitalizing on two routes to solarthermal desalination. First, incorporating a membrane with conical pores as the wicking element will both permit plasmonic heating of functionalized nanoparticles deposited inside the pores, which maximizes light absorption and thus maximizes the overall light to heat conversion, and promote efficient bubble detachment. Secondly, the addition of nanoparticles is expected to increase efficiency by forming vapor bubbles more rapidly and at lower surface temperatures than flat interfaces. Theoretical, numerical, and experimental study is needed to better understand how interactions between the thiolated nanoparticles, interfacial liquid, surface properties and dissolved salts can affect phase transition and heat transfer at the nanoparticle-liquid interface. This study will pave the way for further investigation with the aim of developing practical, cost-effective commercial solar desalination technology.
Aristotle Zervoudakis
Modeling Phase Behavior of Complex Coacervates to Engineer Smart, Responsive Materials
Department of Chemical and Biomolecular Engineering
Faculty Advisor: Jonathan Whitmer
Complex coacervates are a fascinating phase of matter formed when two oppositely charged species of polymer come together, forming a polymer-rich liquid phase that separates from a supernatant phase. What distinguishes this type of phase from others that form in aqueous solution is that, upon phase separation, both phases retain a significant fraction of water content; almost 90% in some cases. The extent of assembly, concentration of polymers, and indeed, the liquidity and viscosity of the phase can be altered through addition of salt, changes in acidity or basicity of solution, and the structure of the polymers used. Importantly, these liquid phases have much in common with solid coatings formed by so-called “layer-by-layer” deposition, with applications to battery electrolytes, protective coatings, and separation membranes. The proposed project is a fundamental study of the structure and thermodynamics of complex coacervates. In particular, while the general properties of these phases are known, and reasonably understood using mean-field Flory-Huggins type models augmented with Debye-Huckel electrolyte theory, both experiments and simulations have recently shown the actual phases to differ. In particular, the salt partition coefficient is different relative to how it appears in the simplest theories. Due to the increasing number of applications for layer-by-layer and coacervate materials in separations and encapsulation processing as well as in novel battery electrolytes, this project has extensive utility for the development of materials impacting energy efficiency and energy storage. In particular, this work serves as a fundamental study in support of collaborative work involving my group and the group of Dr. William Phillip to understand, control, and design new polyelectrolyte functionalized membranes for low energy ion separations. Importantly, by understanding the interplay of acidity and salinity that leads to the formation of liquid and solid associating phases, we may engineer a set of smart, responsive materials which can adapt specific properties to their use cases.