Chemical Engineering Commons^™

Developing A Portable Prototype To Utilize An Electrospun Colorimetric Sensor For The Detection Of Trihalomethanes In Water, Amanda Svensson

Williams Honors College, Honors Research Projects

Trihalomethane (THM) detection in water is important due to the potential health effects caused by their presence, including increased cancer risk. A cheap, quick, and portable method of identifying THM concentration at the Environmental Protection Agency limit of 80 parts per billion (ppb) will improve detection and water treatment. Electrospinning was used to make nanofiber membranes using a 2.6 wt% polypropylene solution. These membranes were utilized in the Fujiwara reaction, which creates a color change in the presence of THMs, to detect the THM bromoform in water. The color intensity of the reaction was quantified for 250 and 80 ppb …

Effects Of Hofmeister Ions On Transition Temperature Of Two Thermo-Responsive Polymers, Joshua Moser

Williams Honors College, Honors Research Projects

It was hypothesized that through the use of Hofmeister Ions, the lower critical solution temperature (LCST) of poly(vinyl methyl ether) (PVME) and poly(ethylene glycol)- poly(N-isopropylacrylamide) (PEG-b-pNIPAAm) block-copolymer could be controlled. Through literature searches and small lab experiments, our team found that there may be a connection between Hofmeister effects and phase transition of a thermo-responsive polymer. To try and prove this, the lab team decided to take four cations (Mg²⁺,Na⁺, Cs⁺, K⁺) in solution with the thermo-responsive polymers and compared their LCST to solutions of the thermo-responsive polymer in de-ionized …

Requalification Of Coated Fabrics Using Chemlok 2332 In Place Of Chemlok 233, Daniel Madler

Williams Honors College, Honors Research Projects

Rubber coated fabrics are an essential component in the deicing systems of the aerospace industry. Adhesives cements are applied to a fabric prior to being pressed into a rubber compound that will adhere to the fabric. The resulting fabric maintains the strength of the fabric with the added benefits of elasticity and compatibility from the rubber compound. UTC Aerospace Systems relies on these coated fabrics to create safe deicers for the aerospace industry. Chemlok 233, a now obsolete primer cement, was used extensively in the coated fabrics used by UTC. Materials testing and performance evaluation allowed for a replacement cement, …

Compression Set Improvement Of Thermoplastic Vulcanizates For High Temperature Tubing, Mitchell Valaitis

Williams Honors College, Honors Research Projects

It was hypothesized that increasing the curative level of the fluorocarbon rubber (FKM) used in manufacturing of thermoplastic vulcanizate (TPV) materials would decrease the compression set values of the TPV enough for it to be suitable as a flexible, lightweight alternative to high operating temperature thermoset rubber tubing currently being used for power steering hose. First, promising TPV formulations were identified by varying the polyamide (PA) and FKM used in a Brabender mixer. Four different types of polyamide and four different types of FKM were investigated, with two of the FKM types and one polyamide type identified as being promising. …

Form Stable Phase-Change Materials, Russell Dent, Marjan Kashfipour, Nitin Mehra, Jiahua Zhu

Williams Honors College, Honors Research Projects

This work investigates the use of two different polyols, xylitol (Xyl) and erythritol (Ery), in conjunction with boron nitride (BN) aerogels, for the purpose of creating thermally conductive composites. While the BN filler in Xyl composites achieved a high anisotropic thermal conductivity of up to 4.53 W/m-K at 18.2 weight percent filler loading, they do not exhibit good phase-change material qualities due to a low solidification enthalpy even at low cooling rates. Alternatively, the BN-Ery composites have shown promising results with a solidification enthalpy of 225.14 J/g and a melting enthalpy of 385.84 J/g at a heat rate of 5 …

Multidimensional Mass Spectrometry Of Chemonic™ Ccg-6 Nonionic Surfactant With Separation By Polarity And Shape, Charles Johnson

Williams Honors College, Honors Research Projects

Chemonic™ CCG-6 surfactant is a water-soluble poly(ethylene glycol) (PEG) conjugated alkyl glyceride emollient. This surfactant exists as a complex mixture of a glycerol cores conjugated with poly(ethylene glycol) branches (PEGylation) that were partially esterified with caprylic (C8) and capric (C10) acids. These may be esterified on one, two, or all three arms of the glyceride. The architecture of the structures in this mixture was studied using multidimensional mass spectrometry (MS). Mass spectrometry was interfaced with ultra-performance liquid chromatography (UPLC) and ion mobility (IM) separation. The mixture was separated by reversed-phase LC, oligomers of the star-branched polymer were separated according to …

Prevention Of Harmful Algal Blooms By The Mitigation Of Phosphorus Nutrient Loading Via Filtration By Steel Wool And Activated Carbon, Ronald Simpson, Sara Kidd, Samantha Zidd

Williams Honors College, Honors Research Projects

Harmful Algal Blooms (HABs) are a devastating ecological and economic consequence of the abundance of nutrient-rich agricultural runoff entering aquatic ecosystems (Baker et al. 2014). Bio-available phosphorus from synthetic fertilizers is one of the major nutrients contributing to this global issue. Previous studies indicated that dissolved phosphorus can be removed from an aqueous environment when passed through a composite mixture of granular steel wool particles and activated carbon (Erickson, Gulliver, and Weiss, 2007). In this project, we conducted experiments using higher quality concentration measurements to determine what grades of steel wool (SW-0000, SW-000, SW-00) and types of activated carbon (granulated …

Sequence Effects On The Glass Transition Temperature, William Drayer

Williams Honors College, Honors Research Projects

Lithium ion batteries are widely used for the energy needs of portable electronic devices. Unfortunately, current liquid organic solvents used as the electrolytic portion of the battery have low thermal stability, resulting in batteries that may combust upon failure. This flammability can be attributed to the configurational strain in cyclic organic electrolytes. Due to the lack of configurational strain in a flexible polymer chain, designing polymer electrolytes for use in lithium ion batteries may result in a safer battery due to their lower flammability in comparison to traditional liquid organic electrolytes. From the perspective of an electrolytic polymer, lowering the …

Development Of Entubulation Strategies For Treating Central Nervous System Injuries, Ivy Brosch

Williams Honors College, Honors Research Projects

According to the McKnight Brain Institute, at least 10,000 people annually in the USA suffer from a central nervous system (CNS) injury. These injuries can cause serve disabilities including paralysis. Due to the complexity of the spinal cord, it is common that potential CNS treatments are first applied to an optic nerve crush (ONC) model in rats. Two proposed treatments were employed; one where nerve growth factor (NGF) was immobilized to a chitosan substrate to stimulate axonal regeneration, and the other using pentadecafluorooctanoyl chloride modified methacrylamide chitosan (MAC(Ali15)F) hydrogel to enhance local oxygenation. The two different treatments were formed into …

Evaluation Of Silane-Doped Epoxy Coatings For Resisting Aluminum Corrosion By Oxalic Acid, An A. Niger Metabolite, Alex Pica

Williams Honors College, Honors Research Projects

The goal of this study was to investigate whether silane-doped epoxy coatings are capable of preventing corrosion of aluminum alloy 2024-T3 by oxalic acid, one of the primary metabolites of the fungus Aspergillus Niger. Previous research suggested the success of these types of coatings at preventing AA 2024-T3 corrosion in saline solutions, and this study was meant to build on those findings by investigating the efficacy of the coating in an acidic environment.

Each coating was applied to an AA 2024-T3 coupon by dissolving the epoxy and varying amounts of 3-aminopropyltriethoxysilane in acetone and then dripping the solution onto …

Environmentally Friendly Alternates To Chemlok 233 Adhesive Cement, Madeline M. Busch

Williams Honors College, Honors Research Projects

The purpose of this project was to determine and qualify suitable, environmentally friendly replacement(s) for the current Chemlok 233 adhesive cement used by UTC Aerospace. Chemlok 233 was discontinued by the manufacturer based on the availability of a hazardous solvent (Trichloroethylene – TCE). The Chemlok 233 Control and four Experimental alternates with similar properties were lab tested for adhesion strength in various UTC proprietary cement specifications. The specifications modeled Chemlok’s uses in the construction of pneumatic de-icers. Chemlok 2332 was selected for use in Cement A, and Chemlok 402 was chosen for use in Cement B based on their highest …

Electrospinning Aqueous Solutions Of Poly(Ethylene Oxide) Using A Corona-Type Apparatus, Nicholas Neill

Williams Honors College, Honors Research Projects

The purpose of this project was to evaluate working parameters for the corona spinneret to create electrospun fibers/ fiber mat. This project was set-up using a Box-Behnken design of experiment. The working parameters were investigated by performing the electrospinning process, altering the working conditions, collecting the electrospun fibers. The scope of this project includes three primary operational conditions: distance between the spinneret and the collection plate, the viscosity (weight percent) of PEO in the spinning solution and the weight percent of NaCl in the spinning solution. The distance between the spinneret and the collection plate were varied to 18 cm, …

Effects Of Hofmeister Ions On Gelation Of Gelatin And Pluronic Hydrogels, Eric Britton

Williams Honors College, Honors Research Projects

The purpose of the project was to observe the effects of the Hofmeister series of ions on the gelation of gelatin and Pluronic-127 hydrogels. Hydrogels are semi-solid materials that contain a network of joined molecules through intermolecular interactions which are capable of holding water. Gelatin and Pluronic-127 (PF-127) are thermoreversible, physical crosslinked gels. Gelation occurs when temperature, or other driving forces, reduce the polymer chain solubility until a distinct 2-phase system forms. When aqueous ions are present in solution, they exhibit specific ion effects that have either a stabilizing or destabilizing effect on the solubility of proteins and other polymers. …

Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong

Williams Honors College, Honors Research Projects

Electrical circuitry is an industry, among many others, heavily using the element of copper. Ensuring the mechanical integrity of Cu is crucial, especially in salt environments, for the multifaceted composition of circuits. 4N NaCl solution (equilibrium concentration in ~84% RH) simulated this three-phase system. Rectangular Cu samples were partially immersed in both ambient and continuous lab air sparging atmospheres to understand waterline corrosion of the metal. Open circuit potentials (OCP) were continuously taken during the immersion testing for a maximum of 5 days. A scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and 3-D …

Tandem Mass Spectrometry (Ms/Ms) For Determination Of Architecture Of Synthetic Polymers, Shoumik Saha

Williams Honors College, Honors Research Projects

Tandem Mass Spectrometry (MS/MS) was used to determine the architecture of synthetic polymers and they are difluorene-N₃, 3-difluorene-N₃ and VPOSS-3-difluorene. VPOSS materials usually exhibit electrochemical properties and the research was performed to determine their accurate structure and to provide evidence of their proper synthesis. The compounds were mixed with a matrix solution, DCTB, and a silver salt to enable proper protonation. The solvent mixture was on a MALDI plate and then put into the mass spectrometer. The mass spectrum generated was analyzed and each fragment was identified to structures with the synthetic polymers via ChemDraw. Thus, trial …

Residence Time Distribution Of Mixing Based On Mathematical Modeling, Michelle Ayers

Williams Honors College, Honors Research Projects

Two different mathematical models were investigated for their use in describing the residence time distribution (RTD) of an industrial mixer. The first model investigated was the tanks-in-series model, while the second model was a combination of two branches of tanks-in-series. The tanks-in-series model is capable of characterizing the mixing present in the flow, but cannot detect non-idealities in flow such as bypassing and dead space. The multi-branch model has mathematical complexity, but it uses the second branch of flow to detect the presence of this non-ideal flow, determine if it is dead space of bypassing, and characterize how well-mixed the …

Sweat Sensor Modelling, Katie Brumbaugh

Williams Honors College, Honors Research Projects

There are no in-situ electrolyte sodium sensors available in the marketplace, however there is a demand and use for them. An in-situ sodium sensor can be used to monitor bodily functioning in many applications like medical patient monitoring and athlete monitoring during workouts. Patients with cystic fibrosis attempt to monitor salt content in sweat to maintain homoeostatic body function, this sweat sensor would change the way those patients took care of themselves [1]. Sweat sensor samples were made using multiwalled carbon nanotubes (MWNT) and nylon 6. The MWNTs were functionalized on the nylon using cyclo-oligomeric calixarene [3]. In functionalizing the …

Investigation Of Scanning Kelvin Probe Techniques, Nicholas D'Angelo Jr., Hongbo Cong

Williams Honors College, Honors Research Projects

The original scope of this work was to advance the understanding of corrosion properties of additively manufactured (AM) materials by correlating microstructural defects in AM materials to the material conventional counterparts utilizing a scanning kelvin probe [Ametek VeraSCAN Electrochemical System]. However, upon the initiation of project research, it was observed that the system was not operational due to unknown hardware and software problems. The evolved scope of this work was to reconcile the operational issues and develop a repair and mitigation plan. After extensive troubleshooting, it was determined that the software was not properly configured, and the electrometer had permanently …

Reaction Kinetics Of The Hydrogenation Of Phenol In A Tubular Reactor, Michael Selzer

Williams Honors College, Honors Research Projects

The reaction kinetic parameters for the hydrogenation of phenol to cyclohexanone are determined for the liquid phase reaction with the palladium catalyst supported on an electrospun PVDF membrane. Runs of the reactor were completed at catalyst loadings of 40, 50, and 60 g/m², and tube diameters of 0.187 in and 0.25 in with a runtime of ten hours. One-dimensional and two-dimensional models of the experimental setup were developed. Fitting data to the one-dimensional model found that the pre-exponential factor was 2.50 x 10⁴, the activation energy was 7.69 kJ/mol, and the order with respect to phenol …

Polyhexamethylene Biguanide Release By Chitosan-Heparin Nanoparticles, Jacob Ress

Williams Honors College, Honors Research Projects

Chitosan and heparin were used to synthesize nanoparticles using polyelectrolyte complexation. The optimal mixing ratio was determined to be 1:4 by studying the particle characteristics of zeta potential and dynamic light scattering of the ratios 1:2, 1:3, 1:4, 1:5 and 1:6 (chitosan: heparin). The particles were loaded with the antibiotic polyhexamethylene biguanide (PHMB) and the release was measured over 335 hours using the dialysis membrane incubation method and detected via ultraviolet-visible (UV-Vis) spectroscopy. Around 80% of the encapsulated PHMB was released over the measured period. The goal of this part of the study was to determine the drug release behavior …

Correlation Of Electrospun Polyvinylpyrrolidone Fiber Mat Thickness With Basis Weight, Fiber Diameter, Pore Size Distribution, And Air Permeability, Leah Mcpherson

Williams Honors College, Honors Research Projects

This project developed correlations between electrospun polyvinylpyrrolidone fiber mat thickness, basis weight, fiber diameter, pore size, and air permeability. The hypotheses were thinner fibers produce thicker mats, pore size decreases with fiber diameter, pore size and permeability decrease as basis weight increases. Project results could be used for modeling or quality control purposes.

Fiber diameter distributions were analyzed using a Scanning Electron Microscope and FibraQuant 1.3 software. Four conditions were chosen for further study: 0.284 ± 0.104 µm, 0.379 ± 0.128 µm, 0.520 ± 0.138 µm, and 0.733 ± 0.177 µm. Lower PVP concentrations produced thinner fibers.

Sample thickness (nm) …

Vanadium Redox Flow Batteries: Design And Experimentation, Matthew George

Williams Honors College, Honors Research Projects

Vanadium flow batteries (VFB) are a type of battery that has potential as a grid-scale energy storage solution. An original design for a lab-scale VFB is presented herein, along with a procedure for electrolyte preparation from V₂O₅ using oxalic acid. The flow cell is constructed from Delrin, Teflon, Kynar, Santoprene, Nafion, graphite plate, and porous carbon. Two diaphragm pumps along with polyethylene, PVC, and Santoprene tubing are used. The active area is 58 cm². The battery was charged using a DC power supply at a constant current of 4 A with corresponding initial voltage of …

Molded Features In Pdms For Fabricating Bacterial Cellulose For Various Geometries, Mitchell Habegger

Williams Honors College, Honors Research Projects

The purpose of producing features on bacterial cellulose (BC) is to facilitate the elongation and alignment for cells, in this case Normal Human Dermal Fibroblast (NHDF) cells. The elongated cells have applications in wound healing, tissue engineering, disease diagnostics, and many other fields. Experiments were run to test the effectiveness of transferring features to BC sheets from features induced by fracturing on polydimethylsiloxane (PDMS) and those duplicated from molds with existing features. The features were duplicated to BC sheets by either air drying or Guided Assembly-Based Biolithography (GAB). The research results showed that fracture inducing on PDMS produced very small …

Modeling The Effect Thickener Structure Has On The Oil Release Of Grease, Dana Cressman

Williams Honors College, Honors Research Projects

Our hypothesis was that the thickener type and micelle concentration of grease affected its viscoelastic properties. Measurements were made using a TA AR G2 rheometer and calculations were made using TA rheometer analysis software to characterize the viscoelastic response of grease under oscillatory shear and frequency tests. The oscillatory frequency tests determined the critical micelle concentration. The oscillatory stress tests were taken at temperatures from 5 to 65 degrees Celsius to create a master curve based on time temperature superposition of the measurements. The crossover points of G’ and G” on the oscillatory stress tests demonstrated where the grease transitions …

Galvanic And Pitting Corrosion Of A Fastener Assembly, Julie Shallman

Williams Honors College, Honors Research Projects

This research focuses on coupled galvanic/pitting corrosion of AA7075 when combined with stainless steel in a fastener assembly. A one-dimensional mathematical model of a well-mixed thin film electrolyte is developed to predict the damage profile of the AA7075 surface when its protective coating is damaged. The damage exposes the galvanic couple. A time dependent system of partial differential equations for potential, chloride concentration, aluminum ion concentration, and damage is developed and solved numerically. Two approaches to calculate the current density within aluminum pits are discussed. The first is a current balance between the cathodic, anodic and passive portions of the …

Protein Release Study Using Heparin Modified Methacrylamide Chitosan Hydrogels, Dakotah G. Cox

Williams Honors College, Honors Research Projects

This study was performed to improve the release of proteins from hydrogels in order to increase their effectiveness in treating spinal cord injuries. Heparin, which has the ability to bind to proteins and slow their release, underwent methacrylation, was added to prepared methacrylamide chitosan (MAC) solutions with a model protein (SDF-1α) and photopolymerized to create MAC-heparin hydrogels. Varying weight percentages of methacrylated heparin were tested in order to determine the optimal amount needed to improve the release profile. The pure MAC hydrogels and gels with 10 wt% heparin had a rapid release of the SDF-1α (>23% and >29%, respectively, …

Process Control Laboratory Skid Refurbishment, Danny Crowder

Williams Honors College, Honors Research Projects

This project evaluates a salvaged process control skid for potential refurbishment and educational re-use. In-lab work evaluated the existing skid. Several process control elements have been recommended for replacement, including the process tank (due to corrosion), the pressure transmitter (operability/corrosion), the flow meters (mechanical) and the control system (age). The control valves, temperature elements and transmitters, pump, holding tanks, and the electrical heat exchanger should be salvaged. An I/P converter and pressure relief valve should be added to the pneumatic feed. Enclosing of all electrical components should be prioritized. An electrical schematic for a new control system should be implemented. …

Effects Of Corrosion Inhibitor On The Corrosion Behavior Of Low Carbon Steel In Co2 Environment, Michael Harris

Williams Honors College, Honors Research Projects

The effectiveness of Benzalkonium chloride (C14) as a corrosion inhibitor for mild steel in an aqueous CO₂ environment was studied for dual use. It is a known biocide and currently untested corrosion inhibitor. Potentiodynamic polarization was used to determine the anodic and cathodic reaction kinetics through analysis of the potentiodynamic curves and the corrosion current densities. Electrochemical impedance spectroscopy (EIS) was utilized to analyze the surface characteristics through analysis of the Nyquist and Bode plots. C1010 and C1018 mild steel were tested in a 200mL jacketed Gamery cell, and purged with CO₂ (99.9%). Temperature effects were studied and …

Evaluation Of Epoxy Coatings For Protecting Aluminum Alloy 2024 From Corrosion Caused By Aspergillus Niger, Kamshat Dukenbaeva

Williams Honors College, Honors Research Projects

The aim of this study was to assess the potentials of using epoxy coatings for the prevention of fungus-induced corrosion. The metal specimen of interest was the aluminum alloy AA 2024-T3. The main intent was to evaluate the behavior of the organic acid producing fungus, Aspergillus niger (A. niger), towards the epoxy-coated aluminum. Two different types of epoxy coatings were used: a two-part resin and a commercially-available Rust-Oleum Specialty Appliance Epoxy. Due to challenges encountered throughout the length of the project and time constraints, limited quantitative data was obtained. However, from optical and visual data it can be concluded that …

Controlled Humidity Chambers To Maintain Red Roses’ Freshness And Improve Their Shelf Life, Rima Vasudevan

Williams Honors College, Honors Research Projects

Floriculture is the third largest agricultural crop in the United States of America. Flowers are usually transported in pots of mud or with the roots still submerged in water to increase their shelf life and ensure freshness during long hours of transport. This not only increases the weight of the transport materials but also makes the process expensive.

The research conducted provides the first stages of an alternative packaging material that can lower the weight of transport materials and maintain the freshness of the flowers. The experiments conducted in this work support the hypothesis that using controlled high (>60%) …