Engineering Commons^™

The Role Of Microenvironment Reagent Solubility On Reaction Kinetics Of 4-Nitrophenol Reduction, Michael P. Zeevi, Andrew Harrison, Christina Tang

Undergraduate Research Posters

The Role of Microenvironment Reagent Solubility on Reaction Kinetics of 4-Nitrophenol Reduction

Michael Zeevi¹ with Andrew Harrison¹ and Christina Tang, PhD¹

¹Department of Chemical and Life Science Engineering, VCU School of Engineering

Introduction: Nanoparticles are of increasing interest due to their high surface area to volume ratio, as well as that they enable fine-tuning of the reaction microenvironment. Through flash nanoprecipitation, core-shell polymer nanoreactors were formed by directed self-assembly. Using the reduction of 4-nitrophenol as a model reduction reaction, we investigated the effect of reagent solubility in the nanoreactor microenvironment’s on nanoreactor kinetics.

Methods: The standard …

Novel (Cu-Sn) And (Ni-Sn) Catalysts Prepared By Mechanical Alloying, Sakollapath Pithakratanayothin

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research was aimed to synthesize intermetallic catalysts using mechanical alloying (Ma) technique. Copper (Cu) and nickel (Ni) were chosen to study since not only their properties are closed to the noble metal properties, e.g. platinum and palladium, but also they are not expensive. However, as also found in noble metals, both Cu and Ni metals are oxidized easily in air. To overcome this problem, either Cu or Ni was mixed with tin (Sn) to obtain bimetallics, viz. CuSn or NiSn, respectively. Therefore, this research was focused on finding the optimal conditions to synthesize both CuSn and NiSn bimetallics using …

Design And Analysis Of Curcumin Conjugated Poly(Beta-Amino Ester) Networks For Controlled Release In Oxidative Stress Environments, Carolyn T. Jordan

Theses and Dissertations--Chemical and Materials Engineering

Oxidative stress, the imbalance of free radical generation with antioxidant defenses, leads to cellular inflammation, apoptosis and cell death. This compromised environment results in debilitating diseases, such as oral mucositis (OM), atherosclerosis, and ischemia/reperfusion injury. Antioxidant therapeutics has been a proposed strategy to ameliorate these imbalances and maintain homeostatic environments. However, the success of these approaches, specifically curcumin, has been limited due to characteristics such as hydrophobicity and high reactivity when released as bolus doses to contest to oxidative stress induced diseases. The development of a controlled release system to aid in protection of the antioxidant capacity of curcumin, as …

Green Composites Of Polylactic Acid Filled With Natural Fiber For Biodegradation Application, Chamaiporn Yamoum

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focuses on how to use natural fibers available from agricultural residues to produce biodegradable materials such as mulch films. Green composites were prepared from natural fibers (peanut shell and bagasse fiber) and polylactic acid (PLA) together with plasticizers. The presence of plasticizers improved PLA molecular mobility as seen by the reduction of glass transition, cold crystallization, and melting temperatures. The addition of natural fibers into PLA brought down decomposition temperature when compared to PLA. The morphological study of the composites showed poor interfacial adhesion between natural fibers and PLA matrix. Moreover, the loading of plasticizers improved distribution of …

Methane And Carbon Dioxide Adsorption On Al-Based And Zr-Based Mofs: Effects Of Amino-Functionalization, Orawee Lamoonkit

Chulalongkorn University Theses and Dissertations (Chula ETD)

For natural gas storage, adsorbed natural gas (ANG) technology has attracted great attention. There is a wide range of porous materials for ANG, but the most promising porous adsorbents for natural gas are metal organic frameworks (MOFs). This study examined adsorption of carbon dioxide and methane gases on aluminium (Al) based MOFs and zirconium (Zr) based MOFs including MIL-53(Al), MIL-53(Al)-NH₂, UiO-66, UiO-66-NH₂ 25%, UiO-66-NH₂ 50%, UiO-66-NH₂ 75%, and UiO-66-NH₂. Experiments were carried out in a static system at 33°C and pressures up to 100 psi. Characterization and structural analysis of the adsorbents were investigated by Fourier transform infrared spectroscopy (FTIR), …

Detergency Of Mixed Oily And Particulate Soils By Single And Mixed Surfactant Systems, Thanawan Teerasathittham

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research studies the detergency performance of mixed surfactants of (anionic and nonionic surfactants) for mixed oily and particulate soils on polyester/cotton blend fabric, and compares with a commercial liquid detergent. Palm oil and kaolinite are used as representatives of oily soil and particulate soil, respectively. The anionic surfactants used in this study are methyl ester sulfonate (MES), linear alkyl benzene sulfonate (LAS) and sodium dodecyl sulfate (SDS). The nonionic surfactants are alcohol ethoxylate 7EO (AE7) and alcohol ethoxylate 9EO (AE9). The effect of surfactant concentrations, NaCl concentration, and mixing ratios of the selected surfactant formulations on detergency performance are …

Green-House Gas Storage Through Enhanced Hydrate Formation, Thiphakorn Absuwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The CO₂ hydrate formation in the presence of different tetrahydrofuran (THF), sodium dodecyl sulfate (SDS), and methyl ester sulfonate (MES) concentrations was investigated in terms of kinetics and thermodynamics. The formation experiment was conducted in the quiescent condition and close system at 3 MPa and 3 °C. The results showed that the CO₂ hydrates formed in the presence of 10 mol% THF, while it did not form with 5.56 mol% THF. The presence of SDS or MES did not promote the hydrate formation. However, the hydrates formed in the presence of a mixture of SDS or MES with 5.56 mol% …

Optimization Algorithm Study : Mixed Integer Linear Programming, Tittawat Fongchantuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the present, many petrochemical and petroleum products (engine fuel, solvent, plastic and synthetic rubber. etc.) are important. They are transported by ship, pipe line or train every day. So, minimizing transportation cost and time or maximizing profit is an important key of every company. In this optimization process, the optimal supply chain must be well developed in mathematical programming with the objective function of minimum cost or maximum profit and be solved by using optimization solvers. Objective functions and their constraints are solved by suitable types of optimization solvers: Linear programming (LP) and mixed integer linear programming (MILP). MILP …

Light Responsive With Metallo-, And Hydrogen Bonded Benzoxazine Dimer-Based Supramolecular Structure, Sorapat Niyomsin

Chulalongkorn University Theses and Dissertations (Chula ETD)

The present work focuses on multi-responsive molecule based on supramolecular chemistry of benzoxazine dimer as a benzoxazine supramolecular crosslinker, fluorescent labelling benzoxazine conjugated with rotaxane system and benzoxazine pendant group block copolymer. The use of azobenzene derivatives in benzoxazine synthesis provides light responsive behaviour. The remained hydroxyl group from aminoalcohol allows benzoxazine to conjugate with desired functional group. The dihydroxyl benzoxazine acts as molecular crosslinker for poly(acrylic acid) by conjugation. The ring-opening reaction brings benzoxazine dimeric unit on the crosslinker which also showed metal ion complexation. The complexation strengthens the cross-linked polymer network. The complex can reversely form by treating …

Catalytic Applications Of Cuo Loaded Mesoporous Ceo₂ And Cuo Loaded Mesoporous Ceo₂-Zro₂ Catalyst, Sureerat Jampa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Copper oxide (CuO) loaded mesoporous ceria (CeO₂) and Copper oxide (CuO) loaded mesoporous ceria-zirconia (CeO₂-ZrO₂) catalysts are successfully synthesized for preferential oxidation of CO (CO-PROX) and autothermal steam reforming of methanol (ASRM). Mesoporous CeO₂ and mesoporous CeO₂-ZrO₂ as catalyst supports with high specific surface area and ordered structure are prepared via a nanocasting process by using MCM-48 as template. Deposition-precipitation technique is chosen to load various Cu contents (1 to 9 wt.%) on the synthesized mesoporous supports. The synthesized CuO loaded mesoporous CeO₂ (Cu-C) and CuO loaded mesoporous CeO₂-ZrO₂ (Cu-CZ) catalysts are characterized by N₂ adsorption-desorption, X-ray diffraction, transmission electron …

Development Of Composite Polyelectrolyte Complex Membrane For Cationic Dye And Heavy Metal Sorption, Wanwanut Chueasupcharoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

The sorption process is most useful in water treatment because it provides high sorption efficiency, low cost and rapid method. Polyelectrolyte complex (PECs) is a novel polymeric membrane prepared by mixing between oppositely charged polyelectrolyte solution of PDADMAC and PSS. Activated carbon (ACs) is used to improved adsorption efficiency in PECs. Non-stoichiometric PDADMAC/PSS membrane were prepared by mixing excess PSS concentration to get the negative charges on the membrane surface. Sorption efficiency was evaluated by methylene blue, cationic dye and heavy metal ions based on the same material, the difference sorption mechanism were observe. In the cationic dye, the adsorption …

Surface Engineering And Monomer Design For Light-Mediated Ring Opening Metathesis Polymerization, Ishan A. Fursule

Theses and Dissertations--Chemical and Materials Engineering

Stimuli-responsive materials are changing the landscape of actuated materials, optoelectronics, molecular machines, solar cells, temporary memory storage, and biomedical materials. Specifically, photo-responsive polymers have gained acceleration in research and application since the last two decades in the form of a surface coating and micro-patterns. Light as a stimulus can be coherent, mono or polychromatic, tunable for power (intensity) and energy (wavelength), and has precise spatiotemporal control. Conventional surface coating techniques such as spin coating are unable to impart properties to the coatings in terms of sturdiness, homogeneity, uniformity over the complex surface, post deposition modification, and process efficiency. Also, in …

Surface Functionalization Via Photoinitiated Radical Polymerization For Rare Cell Isolation And Mechanical Protection, Calvin Frank Cahall

Theses and Dissertations--Chemical and Materials Engineering

Surface functionalization of living cells for cell therapeutics has gained substantial momentum in the last two decades. From encapsulating islets of Langerhans, to cell laden gels for tissue scaffolds, to individual cell encapsulation in thin hydrogels, to surface adhesives and inert surface camouflage, modification of living cell surfaces has a wide array of important applications. Here we use hydrogel encapsulation of individual cells as a mode of protection from mechanical forces for high throughput cell printing, and chemical stimuli for the isolation of rare cells in blood.

In the first study, we review methods of surface functionalization and establish a …

Production Of Biojet Fuel From Palm Fatty Acid Distillate Over Ni/Hzsm-12 Catalyst, Chayanee Hiranyasiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Generally, jet fuels are mainly derived from the refining of petroleum feedstock which exhaust greenhouse gases. Therefore, biojet fuel is introduced as an alternative way to solve the problem. Moreover, jet fuel must have a freezing point about -47 °C or below so iso-paraffins which have low freezing point are required. In this study, the hydroprocessing of palm fatty acid distillate (PFAD) over synthesized Ni/HZSM-12 and conventional Ni/HY catalysts which have different morphology and pore size for producing biojet fuel (hydrocarbon in a range of C9-C14) was studied in a continuous flow fixed-bed reactor under conditions of 350-400 °C, 10-30 …

Chance Constrained Optimization For Petrochemical Supply Chain With The Validation Technique, Kan Rungphanich

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, the profit is more concern in industry due to high business competition. Therefore, reducing the cost is needed to survive competition. Stochastic optimization had been interesting method to reduce opportunity and over-demand loss in the supply chain under uncertainties. Chance constrained optimization is one of the approaches to stochastic optimization. The uncertainties are included in chance constraint of event under level of confidence. This method is used to design the realistic supply chain giving more stabilities than deterministic optimization. The two case studies have been used to show the effectiveness of chance constrained optimization: the simple supply chain network …

The Combined Material Flow Analysis And Life Cycle Assessment For Integrated End-Of-Life Of Mercury Contaminated Petroleum Waste Management, Putthita Chongchongprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Now a day, the waste management generated by offshore petroleum operation (including drilling and production) located in the Gulf of Thailand seem to be a great challenge. Because of their unique characteristic in terms of hazardous properties, petroleum waste requires particular treatments to reduce potential impacts to the environment and human life. This study, the petroleum waste by their disposal code, and waste code was sorted. The Hg-contaminated petroleum waste flow starting from waste generation towards to final disposal was conducted by Material Flow Analysis (STAN, 2.6.601) and Life Cycle Assessment (SimaPro 8.3.0.0) was conducted as tools for evaluating the …

Novel Microemulsion Formation By The Hydrophilic- Lipophilic Deviation Concept Using Carboxylate Extended Surfactants For Eor Application, Suchawadee Kumkhuntod

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Winsor type III (middle phase) microemulsion formation is widely used for enhanced oil recovery (EOR) application. A novel carboxylate surfactant has been an attractive surfactant for the oil recovery due to high chemical stability in harsh reservoir conditions (i.e., high brine concentration and high temperature). This study aims to formulate the middle phase microemulsion in order to obtain the minimum IFT and high solubilization capacity with binary anionic surfactant system using sodium dioctyl sulfosuccinate (AOT) and carboxylate extended surfactants with varying the polyethylene oxide number (EO = 2, 4 and 6) at three mixing molar ratios of 5:5, 7:3 …

Evaluation Of Environmental Impacts For Non-Metallic Part In Waste Printed Circuit Boards (Pcbs) Using Combined Material Flow Analysis (Mfa) And Life Cycle Assessment (Lca), Warisara Rungsitikul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Printed circuit boards (PCBs) have become common components in most electric and electronic equipment. Because of their wide ranges of application, waste PCBs is becoming one of the most rapidly growing wastes. Recycling of waste PCBs is an important subject not only for the protection of the environment but also for the recovery of valuable metals. This study aimed to evaluate the waste PCBs management strategies using the combination of material flow analysis (MFA, STAN v.2.6.801) and life cycle assessment (LCA, SimaPro v.8.3.0.0) methods. The waste management scenario was considered for three different options; disposal of the waste PCBs (Option …

Thermomechanical Behavior And Chemical Sensing Cationic Poly(Diallyldimethylammonium Chloride) And Anionic Poly(Sodium 4-Styrene Sulfonate) Assembled Into Composite Polyelectrolyte Multilayer Thin Films And Complex Membranes, Rateeya Saikaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Polyelectrolyte composite membranes of cationic PDADMAC and anionic PSS assembled into polyelectrolyte multilayer (PEM) thin film and polyelectrolyte complex (PEC) membranes were used as matrix embedded with several additive molecules. Nano-scale PEM films fabricated using the layer-by-layer deposition method and the loading and release of a hydrophobic model drug curcumin (Cur) was studied for drug delivery and sensing applications. Interestingly, it was found that the loading and release of Cur could be triggered by solvent composition and temperature. In a parallel study, the alternative to the nanoscale PEM was studied in the form of PEC, which were used as stand-alone …

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. …

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, …

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 …

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 …

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) …

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 …

Investigation Of Mechanical, Electrical, And Thermal Properties Of Particulate/Fiber/Polymer Composites, Julie Tomasi

Dissertations, Master's Theses and Master's Reports

Composites have many applications due to their high strength to weight ratio, chemical resistance, and the ability to tune properties like electrical resistivity (ER). In this work, polyetheretherketone (PEEK) and cycloaliphatic epoxy (CE) composites with different fillers were studied. PEEK composites contained up to 10 wt% Akzo Nobel Ketjenblack carbon black (CB), up to 15 wt% Asbury Carbons TC307 graphene nanoplatelets (GNP), up to 30 wt% Solvay carbon fiber (CF), and combinations of the three carbons. Formulations were developed for electrostatic dissipative and electrically conductive applications. The most conductive formulation was 7.5 wt% CB/30 wt% CF/PEEK, which had an electrical …