Chemical Engineering Commons^™

Molecular Understanding And Design Of Deep Eutectic Solvents And Proteins Using Computer Simulations And Machine Learning, Usman Lame Abbas

Theses and Dissertations--Chemical and Materials Engineering

Hydrophobic deep eutectic solvents (DESs) have emerged as excellent extractants. A major challenge is the lack of an efficient tool to discover DES candidates. Currently, the search relies heavily on the researchers’ intuition or a trial-and-error process, which leads to a low success rate or bypassing of promising candidates. DES performance depends on the heterogeneous hydrogen bond environment formed by multiple hydrogen bond donors and acceptors. Understanding this heterogeneous hydrogen bond environment can help develop principles for designing high performance DESs for extraction and other separation applications. This work investigates the structure and dynamics of hydrogen bonds in hydrophobic DESs …

Molecular Understanding Of Zwitterions And Quantum Computing For Sustainability, Manh Tien Nguyen

Theses and Dissertations--Chemical and Materials Engineering

The sustainable development of society needs sustainable energy solutions and the mitigation of greenhouse gas emissions. One key subject in this area is the development of safe and efficient ion-based batteries. Moreover, CO₂ capture is a crucial pathway in mitigating emissions from the combustion of fossil fuels. Ongoing efforts are to improve both technologies' safety and efficiency. This thesis presents our efforts to conduct computational research on understanding advanced zwitterionic electrolytes and CO₂ capture. Chapters 2-4 illustrate the computational research to understand ionic solvation in zwitterionic electrolytes. Solid-state electrolytes are essential for safer batteries. While solid polymer electrolytes …

Effects Of Confinement On Ionic Liquids And Deep Eutectic Solvents For The Design Of Catalytic Systems, Electrochemical Devices, And Separations, Andrew Drake

Theses and Dissertations--Chemical and Materials Engineering

Confinement of ionic liquids (ILs) and deep eutectic solvents (DESs) within mesoporous materials such as silica helps to control the local environment within the pores for applications such as catalysis, electrochemistry, and absorption. Silica thin films with 2.5 and 8 nm pores and micron-sized silica particles with pore diameters of 5.4 and 9 nm were synthesized to study the effect of nanoconfinement on ILs 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), and DESs reline and ethaline (choline chloride and urea or ethylene glycol). Silica thin films with vertically aligned, well ordered, and accessible pores were synthesized via the evaporation-induced …

Development Of Soluble Bioactive Poly(Beta Amino Esters) (Pβaes) For Post-Synthesis Processing, Kelley Wiegman

Theses and Dissertations--Chemical and Materials Engineering

Polymers have proven to be a viable platform to facilitate the controlled and targeted release for a variety of therapeutic agents. Polymeric prodrugs are a growing area of drug delivery in which active pharmaceutical ingredients are covalently linked to a polymeric form in an effort to enhance stability, delivery, and pharmacology. One naturally occurring class of active ingredients, known as polyphenols, can potentially offer a vast array of beneficial therapeutic properties. However, the therapeutic efficacy of these compounds is severely limited due to poor solubility and bioavailability as well as an oxidative and thermal instability. To improve the efficacy of …

Versatile Functionalization Strategy For The Capture Of Antibodies Using Silica Nanoparticles, Sayma Afrin

Theses and Dissertations--Chemical and Materials Engineering

In this work, the synthesis of protein-functionalized nonporous silica nanoparticles and their application to capture antibodies was demonstrated. Silica nanoparticles were chosen as they offered particle and pore size tunability, low toxicity, thermal stability, ease of synthesis and ease of surface functionalization. A biotin-streptavidin-biotin bridge was constructed on the surface of the particles and used to attach biotinylated Protein A/G (PAG), which has high affinity for antibodies. The biotin-streptavidin-biotin bridge is hypothesized to orient the PAG in a favorable manner for efficient antibody capture. Nonporous silica nanoparticles (approximately 270 nm in diameter) were synthesized via the Stöber method. Following amine …

Photocatalytic Degradation Of Lignin By Supported Silver Nanoparticles, Ning Wei

Theses and Dissertations--Chemical and Materials Engineering

Lignin is the second most abundant form of biomass on earth. The phenolic structure and high carbon to oxygen ratio make lignin an attractive renewable source of fuel and chemicals. However, its recalcitrance and heterogeneous nature prove difficult for decomposing lignin’s polymer structure and separation of the products. This work has focused on the use of low-energy catalytic approaches to overcome these barriers. A mimic of the lignin degrading enzyme laccase, consisting of a copper cluster Cu4Py4I4 modified with AgNO3, was developed to function similarly to the laccase active site. The prepared copper complex solution was found to be active …

Development Of Novel Polymeric Materials For Their Application In Monitoring And Remediation Of Environmental Pollutants, Rishabh Shah

Theses and Dissertations--Chemical and Materials Engineering

Remediation of environmental pollutants from water is one of the major challenges in the 21st century. Utilizing novel polymeric materials to accomplish this challenge has garnered a lot of interest in recent times. Flexibility in synthesizing as well as functionalizing makes them attractive for their application in pollutant remediation. This work is based on development and characterization of novel crosslinked polymeric as well as linear polymeric materials from biphenyl-based monomers, biphenyl based crosslinker and a temperature responsive monomer (Nisopropylacrylamide (NIPAAm)) for their application in remediation of toxic pollutants such as polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) and iron oxide nanoparticle …

Optimization Of Gelatin-Based Cellular Coating Of Msc For Myocardial Infarction Therapy, Kara Amelle Davis

Theses and Dissertations--Chemical and Materials Engineering

Cardiovascular disease remains the number one threat to American lives. During an acute myocardial infarction (AMI), blood flow is blocked and results in the formation of scar tissue. As the body’s immune system responds, inflammatory signaling causes an increase in both scar tissue size and the patient’s risk for further chronic heart failure. In order to reduce the risk of continued heart disease inflammatory signaling must be reduced. Stem cell therapies have the ability to alter the immune system’s pro-inflammatory signal. However, stem cell retention is limited due to blood flow shear. Gelatin methacrylate (GelMA) based coatings have been shown …

Tailoring Thermoresponsive Poly(N-Isopropylacrylamide) Toward Sensing Perfluoroalkyl Acids, Dustin Thomas Savage

Theses and Dissertations--Chemical and Materials Engineering

Widespread distribution of poly- and perfluoroalkyl substances (PFAS) in the environment combined with concerns for their potentially negative health effects has motivated regulators to establish strict standards for their surveillance. The United States Environmental Protection Agency issued a cumulative domestic threshold of 70 ppt for water supplies, and this bar is even lower in some local districts and other countries. Monitoring PFAS consequently requires sensitive analytical equipment to meet regulatory specifications, and liquid chromatography with tandem mass spectroscopy (LC/MS/MS) is the most common technique used to satisfy these requirements. Though extremely sensitive, the instrument is often burdened by pretreatment regimens, …

Assessment Of A Decentralized Solution For Waste Plastic Management In Developing Regions, Chandniben Ashishkumar Joshi

Theses and Dissertations--Chemical and Materials Engineering

Rapid population growth, urbanization and availability of pre-packaged consumer goods have led to increased generation and consumption of plastic – so much so that it has become ubiquitous in the environment. An affordable, durable, and lightweight material of construction, plastic is used in innumerable products in every country on earth. However, this explosion of consumption coupled with the material’s significantly low degradability have led to serious plastic accumulation challenges, which are now an imminent threat to terrestrial and marine species globally. These challenges are especially acute in developing countries, where capital and infrastructure constraints, poor governmental regulation and lack of …

Interactions Of Lignin Dimers With Engineered Surfaces And Model Cell Membranes For Design Of Lignin-Based Materials, Mahsa Moradipour

Theses and Dissertations--Chemical and Materials Engineering

Capitalizing on byproducts of industrial and agricultural economies is among the utmost goals of sustainability. Of particular interest for commercial upgrading is lignin, a phenolic biopolymer found in the cell walls of plants which is the second most abundant biopolymer on Earth after cellulose. Due to its heterogeneous structure, deconstructing lignin to selected small molecules for use as chemicals or advanced materials has been elusive. This work capitalizes on a “bottom up” approach to the synthesis of lignin oligomers of known bond chemistry to better understand their interfacial interactions.

The potential pharmacological mechanism of lignin deconstruction components and their toxicological …

Microfiltration Membrane Pore Functionalization Approaches For Chloro-Organic Remediation To Heavy Metal Sorption, Mohammad Saiful Islam

Theses and Dissertations--Chemical and Materials Engineering

Microfiltration polyvinylidene fluoride (PVDF) membranes have distinct advantage for open structure in terms of high internal surface area and ease of access in the pore domain. Functionalization of PVDF membranes with different functional groups (-COOH, -OH, -SH) enables responsive (pH, temperature) properties to membrane, tuning of effective pore size, controlling permeate flux. PVDF microfiltration membrane functionalization with suitable responsive polymer such as poly acrylic acid (PAA) to incorporate carboxyl (-COOH) group enables further modification of functionalized PAA-PVDF membranes for different application ranging from catalysis, bio reactor to heavy metal sorption platform. As a catalytic reactor bed, this PAA-PVDF membranes are …

A Framework For Heterologous Biosynthesis Of Natural Products In Mammalian Cells Via Polymer-Mediated Transfections, Logan Warriner

Theses and Dissertations--Chemical and Materials Engineering

With the promise to treat a multi-faceted list of serious inherited and acquired diseases, such as cancer, neurodegenerative and infectious diseases, and inherited genetic indications, gene therapy has continued to push the boundaries of traditional medicine since its earliest implementation. While much progress has been made, clinical success has largely remained elusive. Immunogenicity, difficulty producing commercially relevant quantities, and having a limited genetic payload still limits the ability of viruses to act as directed delivery agents for genetic material. As such, researchers have turned to cationic synthetic materials as a means of delivering nucleic acids, which can circumvent the immune …

Polymeric Nanocomposite Membranes With Phosphorene Based Pore Fillers For Fouling Control, Joyner Eke

Theses and Dissertations--Chemical and Materials Engineering

Phosphorene is a two-dimensional material exfoliated from bulk phosphorus. Specifically, relevant to the field of membrane science, the band gap of phosphorene provides it with potential photocatalytic properties, which could be explored in making reactive membranes able to control the accumulation of compounds on the surface during filtration, or fouling. Another reason phosphorene is a promising candidate as a membrane material additive is due to its catalytic properties which can potentially destroy foulants on the membrane surface.

The first goal of this study was to develop an innovative and robust membrane able to control and reverse fouling with minimal changes …

Bimetallic Nanoparticles Integrated Membranes For Groundwater Remediation: Synthesis, Characterization And Applications, Hongyi Wan

Theses and Dissertations--Chemical and Materials Engineering

The detoxification of chlorinated organics from groundwater, such as trichloroethylene (TCE), tetrachloroethylene (PCE), polychlorinated biphenyl (PCB) and carbon tetrachloride (CTC), is a challenging area. Reductive dechlorination has been investigated using iron and iron-based nanoparticles, such as bare Fe, sulfidized Fe (S-Fe) and palladized Fe (Pd-Fe). However, issues including particle agglomeration, difficulties in recycling and particle leaching have been reported to hinder the application and wide usage of these techniques. The integration of nanoparticles and membranes can address these issues because of the large surface area, stability, and the potential for versatile functionalities. In this study, commercial polyvinylidene difluoride (PVDF) microfiltration …

Characterization And Electrochemical Performance Of Dopamine-Sensitized Titania Thin Films, Joshua Garay

Theses and Dissertations--Chemical and Materials Engineering

Sensitization of mesoporous titania films with dopamine and polydopamine for visible light photoelectrochemical activity is investigated. Sensitization effectiveness is compared with 8 mM dopamine solutions of varying pH (acidic, basic, and neutral), as well as with a basic polydopamine solution. Vibrational changes due to dopamine attachment are determined from detached powders by Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) is used to quantify organics attached. X-ray photoelectron spectroscopy (XPS) of intact films probes the chemically induced charge shift from dopamine attachment. Cyclic voltammetry identifies the irreversible dopamine oxidation and tin reduction voltages. Finally, chronoamperometric curves are used to compare …

Silica Nanoporous Confinement Effects On Ionic Liquid Properties For Better Design Of Small Molecule Separation, Electrochemical Devices And Drug Delivery, Yuxin He

Theses and Dissertations--Chemical and Materials Engineering

Silica nanoconfinement provides a high level of control of ionic liquids (ILs) in localizing catalysts, creating distinct environment for tuning reactivity and controlling the partition of solvents, reactants and products. Silica thin films with two different pore sizes (2.5 nm and 8 nm) were synthesized to study the effect of nanopore confinement on ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]), and 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). Silica thin films with accessible 8 nm pore diameters were synthesized using evaporation-induced self-assembly (EISA) with Pluronic P123 as templating surfactant on a chemically neutral modified substrate. The silica films with similar orthogonal aligned mesostructured but …

The Development Of Temperature And Ph Responsive Hydrogels And Membranes For Selective Sorption Of Perfluoroorganics And Nanoparticle Integrated Catalytic Degradation Of Pcb, Anthony Saad

Theses and Dissertations--Chemical and Materials Engineering

The functionalization and use of responsive and catalytic polymeric membranes and materials were explored for contaminant capture and degradation. While membranes have a wide variety of uses across multiple industries, the inclusion of materials that are temperature and pH responsive in the membrane pore domain yields a wide range of applications and possibilities for water treatment. Temperature and pH responsive polymers, as well as controlled nanostructured materials, were synthesized in membrane pores for advanced adsorption-desorption and catalytic treatment of emerging organic contaminants in water. In this study, supported by the NIEHS, poly-N-isopropylacrylamide (PNIPAm) was used as a model thermo-responsive polymer, …

Effect Of Silica Nanoconfinement Of Lipid Bilayers On Its Phase Transition And On The Colloidal Stability Of Silica Nanoparticles, Aniruddha Atul Shirodkar

Theses and Dissertations--Chemical and Materials Engineering

In this work, we incorporated 4-(N-Boc-aminometyl) phenylboronic acid (BA), at different concentrations, into 1,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC) bilayers confined within nanopores of two different mean pore diameters of 7.4 nm and 11.7 nm of micron sized silica particles. The confinement of DPPC into nanopores resulted in the depression in the main phase transition temperatures compared to the liposomal system. The addition of BA was found to induce disruptions in the acyl chains of the lipid molecules at all concentrations of the solute. The lipid bilayer cooperativity was found to be higher in the confined systems compared to the liposomal systems despite …

Fabrication, Characterization And Applications Of Highly Conductive Wet-Spun Pedot:Pss Fibers, Ruben Sarabia Riquelme

Theses and Dissertations--Chemical and Materials Engineering

Smart electronic textiles cross conventional uses to include functionalities such as light emission, health monitoring, climate control, sensing, storage and conversion of energy, etc. New fibers and yarns that are electrically conductive and mechanically robust are needed as fundamental building blocks for these next generation textiles.

Conjugated polymers are promising candidates in the field of electronic textiles because they are made of earth-abundant, inexpensive elements, have good mechanical properties and flexibility, and can be processed using low-cost large-scale solution processing methods. Currently, the main method to fabricate electrically conductive fibers or yarns from conjugated polymers is the deposition of the …

Nanostructured Metal Thin Films As Components Of Composite Membranes For Separations And Catalysis, Michael J. Detisch

Theses and Dissertations--Chemical and Materials Engineering

Novel metallic thin film composite membranes are synthesized and evaluated in this work for improved separations and catalysis capabilities. Advances in technology that allow for improved membrane performance in solvent separations are desirable for low molecular weight organic separation applications such as those in pharmaceutical industries. Additionally, the introduction of catalytic materials into membrane systems allow for optimization of complex processes in a single step. By adding a nanostructured metallic thin film to its surface, a polymer membrane may be modified to exhibit these improved properties. Using magnetron sputtering, thin metal films may be deposited on commercially available membranes to …

A Thermodynamic And Feasibility Study Of Green Solvents For The Fabrication Of Water Treatment Membranes, Xiaobo Dong

Theses and Dissertations--Chemical and Materials Engineering

Nonsolvent induced phase separation (NIPS) has been widely used to fabricate polymeric membranes. In NIPS, a polymer is dissolved in a solvent to form a dope solution, which is then cast on a substrate and immersed in a nonsolvent bath, where phase inversion occurs. Petroleum-derived organic solvents, such as N-Methyl-2-Pyrrolidone (NMP) and Dimethylacetamide (DMAc), have been traditionally used to fabricate polymeric membranes via NIPS. However, these solvents may have negative impacts on environmental and human health; therefore, using greener and less toxic solvents, preferably derived from biomass, is of great interest to make membrane fabrication sustainable. In this dissertation, two …

Mechanical Properties And Degradation Of High Capacity Battery Electrodes: Fundamental Understanding And Coping Strategies, Yikai Wang

Theses and Dissertations--Chemical and Materials Engineering

Rechargeable lithium ion and lithium (Li) metal batteries with high energy density and stability are in high demand for the development of electric vehicles and smart grids. Intensive efforts have been devoted to developing high capacity battery electrodes. However, the known high capacity electrode materials experience fast capacity fading and have limited cycle life due to electromechanical degradations, such as fracture of Si-based electrodes and dendrite growth in Li metal electrodes. A fundamental understanding of electromechanical degradation mechanisms of high capacity electrodes will provide insights into strategies for improving their electrochemical performance. Thus, this dissertation focuses on mechanical properties, microstructure …

Synthesis, Functionalization, And Application Of Nanofiltration And Composite Membranes For Selective Separations, Andrew Steven Colburn

Theses and Dissertations--Chemical and Materials Engineering

Future nanofiltration (NF) membranes used for selective separations of ions and small organic molecules must maintain performance in environments where high concentrations of total dissolved solvents or foulants are present. These challenges can be addressed through the development of composite membranes, as well as the engineering of enhanced surface properties and operating conditions for existing commercial membranes.

In this work, ion transport through commercial thin film composite (TFC) polyamide NF membranes were studied in both lab-prepared salt solutions and industrial wastewater. The dependence of several variables on ion rejection was investigated, including ion radius, ion charge, ionic strength, and temperature. …

Towards The Rational Design And Application Of Polymers For Gene Therapy: Internalization And Intracellular Fate, Landon Alexander Mott

Theses and Dissertations--Chemical and Materials Engineering

Gene therapy is an approach for the treatment of acquired cancers, infectious disease, degenerative disease, and inherited genetic indications. Developments in the fields of immunotherapies and CRISPR/Cas9 genome editing are revitalizing the efforts to move gene therapy to the forefront of modern medicine. However, slow progress and poor clinical outcomes have plagued the field due to regulatory and safety concerns associated with the flagship delivery vector, the recombinant virus. Immunogenicity and poor transduction in certain cell types severely limits the utility of viruses as a delivery agent of nucleic acids. As a result, significant efforts are being made to develop …

Functionalization Of Iron Oxide Nanoparticles And The Impact On Surface Reactive Oxygen Species Generation For Potential Biomedical And Environmental Applications, Trang Mai

Theses and Dissertations--Chemical and Materials Engineering

Iron oxide nanoparticles (IONPs) have been widely studied for a variety of applications, from biomedical applications (e.g., cell separation, drug delivery, contrast agent for magnetic resonance imaging and magnetically mediated energy delivery for cancer treatment) to environmental remediations (e.g., heavy metal removal and organic pollutants degradation). It has been demonstrated that IONPs can induce the production of reactive oxygen species (ROS) via Fenton/Haber-Weiss reactions which has been shown to be one of the key underlying mechanisms of nanoparticles toxicity. This inherent toxicity of nanoparticles has been shown to enhance the efficacy of traditional cancer therapies such as chemotherapy and radiation. …

Cell Surface Coatings For Mammalian Cell-Based Therapeutic Delivery, Pei-Jung Wu

Theses and Dissertations--Chemical and Materials Engineering

The cell plasma membrane is an interactive interface playing an important role in regulating cell-to-cell, cell-to-tissue contact, and cell-to-environment responses. This environment-responsive phospholipid layer consisting of multiple dynamically balanced macromolecules, such as membrane proteins, carbohydrate and lipids, is regarded as a promising platform for various surface engineering strategies. Through different chemical modification routes, we are able to incorporate various artificial materials into the cell surface for biomedical applications in small molecule and cellular therapeutics.

In this dissertation, we establish two different cell coating techniques for applications of cell-mediated drug delivery and the localization of cell-based therapies to specific tissues. The …

Impact Of Conformational Change, Solvation Environment, And Post-Translational Modification On Desulfurization Enzyme 2'-Hydroxybiphenyl-2-Sulfinate Desulfinase (Dszb) Stability And Activity, Landon C. Mills

Theses and Dissertations--Chemical and Materials Engineering

Naturally occurring enzymatic pathways enable highly specific, rapid thiophenic sulfur cleavage occurring at ambient temperature and pressure, which may be harnessed for the desulfurization of petroleum-based fuel. One pathway found in bacteria is a four-step catabolic pathway (the 4S pathway) converting dibenzothiophene (DBT), a common crude oil contaminant, into 2-hydroxybiphenyl (HBP) without disrupting the carbon-carbon bonds. 2’-Hydroxybiphenyl-2-sulfinate desulfinase (DszB), the rate-limiting enzyme in the enzyme cascade, is capable of selectively cleaving carbon-sulfur bonds. Accordingly, understanding the molecular mechanisms of DszB activity may enable development of the cascade as industrial biotechnology. Based on crystallographic evidence, we hypothesized that DszB …

Development Of Novel Temperature Responsive Polymeric Sorbents And Their Applications In Water Remediation, Shuo Tang

Theses and Dissertations--Chemical and Materials Engineering

Water remediation utilizing sorption has found strong interest due to its inexpensiveness, universal nature and ease of operation. In particular, thermo-responsive sorbents consisting of N-isopropylacrylamide (NIPAAm) offer significant potential as “smart” and advanced materials to remove multiple aqueous pollutants. NIPAAm exhibits excellent thermo-responsiveness, which senses the external temperature variation and changes its swelling and sorption behaviors in a sharp and rapid manner. At the beginning of this work, an extensive review of literature has been compiled to provide a summary of NIPAAm-based thermo-responsive sorbents in water/wastewater remediation applications.

Initially, we developed a novel approach to synthesize and characterize NIPAAm copolymeric …

Nanoharvesting And Delivery Of Bioactive Materials Using Engineered Silica Nanoparticles, Md Arif Khan

Theses and Dissertations--Chemical and Materials Engineering

Mesoporous silica nanoparticles (MSNPs) possess large surface areas and ample pore space that can be readily modified with specific functional groups for targeted binding of bioactive materials to be transported through cellular barriers. Engineered silica nanoparticles (ESNP) have been used extensively to deliver bio-active materials to target intracellular sites, including as non-viral vectors for nucleic acid (DNA/RNA) delivery such as for siRNA induced interference. The reverse process guided by the same principles is called “nanoharvesting”, where valuable biomolecules are carried out and separated from living and functioning organisms using nano-carriers. This dissertation focuses on ESNP design principles for both applications. …