Chemical Engineering Commons^™

Oil Recovery Through Deemulsification Research : Separation Of Water From Emulsified Oil, Aaron Russell, Matthew S. Clay, Christopher A. Cox, Jessica E. Nichols, Summer Scott, Sirikarn Surawanvijit

Chemical Engineering Undergraduate Honors Theses

In an effort to improve the environment, there is a need to recover and reuse the oil and water components of lubricating emulsions used in copper drawing and rolling processes. The Freeport-McMoRan Copper and Gold Inc. copper rod mill located in El Paso, TX was chosen as the site location for this project. It is one of the largest rolling and drawing operation facilities in the world, and it meets the established criteria set by Project ORDER. A large facility generates an average of 8,400 gallons of spent lubricant per day. The WERC emulsion sample contains 98 v% water and …

The Development Of A Computational Model Of Thrombosis In Hemodialysis Catheters, Daniel J. Lattin

Theses and Dissertations

Thromboembolism (TE) significantly limits the usefulness and safety of blood-contacting devices such as hemodialysis catheters. Computer simulation of TE can provide understanding of the process and can facilitate the design of more effective devices. Previous work conducted at BYU successfully modeled TE in a simple, two-dimensional flow cell design by adding quantitative TE code to a commercial computational fluid dynamics (CFD) package, Fluent. This two-dimensional model predicted thrombus initiation and growth and adjusted flow to accommodate thrombus geometries, but was limited by computational power and unsophisticated meshing techniques. To build upon this work, and take advantage of BYU's new supercomputing …

Three-Dimensional Direct Numerical Simulation Of Soot Formation And Transport In A Temporally Evolving Nonpremixed Ethylene Jet Flame, David O. Lignell, Jacqueline H. Chen, Philip J. Smith

Faculty Publications

Three-dimensional direct numerical simulation of soot formation with complex chemistry is presented. The simulation consists of a temporally evolving, planar, nonpremixed ethylene jet flame with a validated, 19-species reduced mechanism. A four-step, three-moment, semiempirical soot model is employed. Previous two-dimensional decaying turbulence simulations have shown the importance of multidimensional flame dynamical effects on soot concentration [D.O. Lignell, J.H. Chen, P.J. Smith, T. Lu, C.K. Law, Combust. Flame 151 (1–2) (2007) 2–28]. It was shown that flame curvature strongly impacts the diffusive motion of the flame relative to soot (which is essentially convected with the flow), resulting in soot being differentially …

Vapor-Liquid Equilibrium Of Polymer Solutions During Thermal Decomposition Of Rigid Foams, Nathan H. King

Theses and Dissertations

Removable Epoxy Foam (REF) and other rigid foams experience severe changes in structure and properties when exposed to high heat. As thermal energy breaks network bonds in the foam many species are formed, including large polymer-like network fragments and smaller solvent-like molecules. During this process a liquid phase may form. The vapor-liquid equilibrium (VLE) behavior of the polymer solutions formed during initial decomposition can be highly non-ideal. In this research VLE behavior of high-temperature polymer solutions was studied and a procedure was developed for predicting that behavior during decomposition of rigid foams. A high-temperature VLE facility was built and validated, …

Microkinetic Model Of Fischer-Tropsch Synthesis On Iron Catalysts, Uchenna Prince Paul

Theses and Dissertations

Fischer-Tropsch synthesis (FTS), developed in the early 1900's, is defined as the catalytic conversion of H2 and CO to hydrocarbons and oxygenates with the production of H2O and CO2. Accurate microkinetic modeling can in principle provide insights into catalyst design and the role of promoters. This work focused on gaining an understanding of the chemistry of the kinetically relevant steps in FTS on Fe catalyst and developing a microkinetic model that describes FTS reaction kinetics. Stable Al2O3-supported/promoted (20% Fe, 1% K, 1% Pt) and unsupported Fe (99% Fe, 1% Al2O3) catalysts were prepared and characterized. Transient experiments including temperature programmed …

Effects Of Moisture On Combustion Of Live Wildland Forest Fuels, Brent M. Pickett

Theses and Dissertations

Current operational wildland fire models are based on numerous correlations from experiments performed on dry (dead) fuel beds. However, experience has shown distinct differences in burning behaviors between dry and moist (live) fuels. To better understand these fundamental differences, an experiment was designed to use a flat-flame burner to simulate a moving fire front which heated and ignited a stationary, individual fuel sample. Samples included various U.S. species from the California chaparral, the intermountain west, and the southeastern regions. Temperature, mass, and video images were recorded throughout each experimental run from which numerous data values were obtained such as time …

Modeling Phase Transitions Of Nanoemulsion For Ultrasonic Gene Delivery, Ghaleb A. Husseini, William G. Pitt, Ram Singh

Faculty Publications

A computer model was written that simulates the transformation of a nanoemulsion droplet to a gas bubble by the application of ultrasound. Experimentally such a technique could be used to enhance non-viral gene transfection beyond the boundary of the endothelial lining of the circulatory system, particularly in tumors exhibiting enhanced permeation and retention of nanoparticles.

A Simulation Of The Neural Action Potential Under The Influence Of Acetylcholinesterase Inhibitors Modeled In The Neuromuscular Junction, Frank Jenkins

Doctoral Dissertations

The rise of terrorism has created an interest in better ways to detect when humans are exposed to neurotoxins, especially nerve gases developed for military use, most of which are acetylcholinesterase inhibitors. Many current methods of detection are based on mass spectrometry, a method that is cumbersome and not particularly robust when used as an early warning method. The detection of acetylcholinesterase inhibitors would benefit from a combined model of the processes occurring in the neuromuscular junction between the presynaptic action potential and the motor end-plate action potential that includes the kinetics of acetylcholine and acetylcholinesterase in the synaptic cleft. …

Effect Of Ph On Ptru Electrocatalysts Prepared Via A Polyol Process On Carbon Nanotubes, Li Ren, Yangchuan Xing

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper reports a study on the pH effects on the PtRu nanoparticles synthesized in a polyol process that were deposited on carbon nanotubes (CNTs) by reducing metal salts using ethylene glycol at various pHs. It was found that the nanoparticle size, composition, and catalytic activity all were sensitive to pH. the nanoparticles decreased in size as the preparation pH increased from 1.6 to 10.0, with the largest size at 2.47 nm and the smallest at 1.13 nm. an exception was found for pH at 0.7, which resulted in an average size of only 1.01 nm. Preparation pH was found …

Development And Evaluation Of A Sub-Grid Combustion Model For A Landscape Scale 3-D Wildland Fire Simulator, Michael M. Clark

Theses and Dissertations

A mixture-fraction-based thermodynamic equilibrium approach for modeling gas-phase combustion was adapted and used in FIRETEC, a wildfire computational fluid dynamics model. The motivation behind this work was the desire to incorporate the features of complex chemistry calculations from the thermodynamic equilibrium model into FIRETEC without significantly increasing the computational burden of the program. In order to implement the mixture-fraction-based thermodynamic equilibrium approach, a sub-grid pocket model was developed to simulate the local mixture fraction of sub-grid flame sheets. Numerical simulations of wildfires were performed using FIRETEC with the new sub-grid, mixture-fraction-based pocket model to model gas-phase combustion. The thermodynamic equilibrium …

Modeling Of Electronic And Ionic Transport Resistances Within Lithium-Ion Battery Cathodes, David E. Stephenson

Theses and Dissertations

In this work, a mathematical model is reported and validated, which describes the performance of porous electrodes under low and high rates of discharge. This porous battery model can be used to provide researchers a better physical understanding relative to prior models of how cell morphology and materials affect performance due to improved accounting of how effective resistance change with morphology and materials. The increased understanding of cell resistances will enable improved design of cells for high-power applications, such as hybrid and plug-in-hybrid electric vehicles. It was found electronic and liquid-phase ionic transport resistances are strongly coupled to particle conductivity, …

How Accurate Is Students’ Self Assessment Of Computer Skills?, Michael A. Collura, Samuel Bogan Daniels

Engineering and Applied Science Education Faculty Publications

Self-evaluation by students is commonly used as a key element in program and course assessment plans. Such instruments are intended to provide crucial feedback for program improvement and thus play a significant role in closing our assessment loop. For many of the program outcomes, self-assessment by current students and graduates augments other, more objective measures. However, for some outcomes there are no practical means of obtaining objective assessment and we must rely on self-assessment. The heavy reliance on this metric begs the question “How accurate is student self-assessment?” This paper provides data from a second-semester engineering course in which students …

Fuel Composition Analysis Of Endothermically Heated Jp-8 Fuel For Use In A Pulse Detonation Engine, Eric A. Nagley

Theses and Dissertations

Waste heat from a pulse detonation engine (PDE) was extracted via zeolite catalyst coated concentric tube-counter flow heat exchangers to produce supercritical pyrolytic conditions for JP-8 fuel. A sampling system and method were developed that enabled samples of reacted fuel to be extracted during steady state operation. Samples were taken over a range of heat exchanger exit temperatures from 820 K (1016° F) to 940 K (1232° F). Offline analysis of liquid and vapor fuel samples indicated fuel decomposition via typical pyrolytic reaction pathways. The liquid analysis showed conversion of parent fuel components with formation of unsaturates (aromatics and alkenes) …

Universal Scaling Characteristics Of Stress Overshoot In Startup Shear Of Entangled Polymer Solutions, Sham Ravindranath, Shi-Qing Wang

College of Polymer Science and Polymer Engineering

We have carried out conventional theological measurements to explore the well-known stress overshoot behavior in startup shear of eight entangled polybutadiene solutions. In the elastic deformation regime with (gamma)over dot tau(R)> 1, we have identified universal scaling features associated with the stress maximum sigma(max) for samples of different levels of entanglements per chain ranging from 27, 40 to 64. Specifically, at the moment t(max) of the peak stress sigma(max) where the applied strain is gamma(max) = (gamma)over dott(max): (a) sigma(max) varies linearly with gamma(max), (b) sigma(max) scales with t(max) as sigma(max)similar to(t(max))-1/2. The combination of (a) and (b) yields a …

Building Benchmarks, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

No abstract provided.

Fault Growth And Propagation During Incipient Continental Rifting: Insights From A Combined Aeromagnetic And Shuttle Radar Topography Mission Digital Elevation Model Investigation Of The Okavango Rift Zone, Northwest Botswana, Baraka D. Kinabo, John Patrick Hogan, Eliot A. Atekwana, Mohamed G. Abdel Salam, Motsoptse P. Modisi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Digital Elevation Models (DEM) extracted from the Shuttle Radar Topography Mission (SRTM) data and high-resolution aeromagnetic data are used to characterize the growth and propagation of faults associated with the early stages of continental extension in the Okavango Rift Zone (ORZ), northwest Botswana. Significant differences in the height of fault scarps and the throws across the faults in the basement indicate extended fault histories accompanied by sediment accumulation within the rift graben. Faults in the center of the rift either lack topographic expressions or are interpreted to have become inactive, or have large throws and small scarp heights indicating waning …

Agarose And Methylcellulose Hydrogel Blends For Nerve Regeneration Applications, Benton C. Martin, Eric J. Minner, Sherri L. Wiseman, Rebecca L. Klank, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Trauma sustained to the central nervous system is a debilitating problem for thousands of people worldwide. Neuronal regeneration within the central nervous system is hindered by several factors, making a multi-faceted approach necessary. Two factors contributing to injury are the irregular geometry of injured sites and the absence of tissue to hold potential nerve guides and drug therapies. Biocompatible hydrogels, injectable at room temperature, that rapidly solidify at physiological temperatures (37°C) are beneficial materials that could hold nerve guidance channels in place and be loaded with therapeutic agents to aid wound healing. Our studies have shown that thermo reversible methylcellulose …

Encapsulation And Extended Release Of Anti-Cancer Anastrozole By Stealth Nanoparticles, Kumkum Sarkar, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

To improve delivery efficiency of anastrozole, we applied dendrimer-based stealth nanoparticles to encapsulate anastrozole to formulate stealth anastrozole nanoparticles. This work demonstrated that stealth nanoparticles composed of a PAMAM dendrimers core and a PEG layer could encapsulate anastrozole, hence causing improved water solubility of anastrozole. Anastrozole encapsulation depended on concentration of stealth nanoparticles and generation of dendrimer. The extended release of anastrozole was achieved. We envisioned that this highly structurally adaptable stealth nanoparticle could be further biofunctionalized to construct a targeted therapeutic delivery system for breast cancer treatment.

Local Characteristics Of Hydrodynamics In Draft Tube Airlift Bioreactor, Hu Ping Luo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Airlift Column Reactors Have Been Widely Used in Bioprocesses. the Design, Scale-Up, and Performance Evaluation of Such Reactors All Require Extensive and Accurate Information About the Gas-Liquid Flow Dynamics, Particularly as Computational Fluid Dynamics (CFD) Has Become More Popular in the Last Decade. However, Due to the Limitation of Most Conventional Techniques for Gas-Liquid Flow Dynamics Measurement, Only Global Hydrodynamic Parameters (E.g., Cross-Sectionally Averaged Liquid Circulation Velocity, overall Gas Holdup, and overall Mass Transfer Rate) Have Been Extensively Studied. the Local Flow Characteristics (E.g., the Macro-Mixing and the Turbulence Intensity) Remain Unclear. in This Study, We Use the Computer Automated …

Production Of Nanocrystalline Rdx By Ress : Development And Material Characterization, Victor Stepanov

Dissertations

The aim of the present work was to address the hazardous vulnerability of energetic materials to accidental initiation. An improved form of the explosive RDX with a significantly reduced sensitivity to stimuli including shock and impact was sought. The direction of this research was to investigate the effect of RDX crystal size reduction down to nano-scale dimensions on the sensitivity characteristics. Although size reduction of energetic crystals has been demonstrated often to result in a sensitivity reduction, the effect at the nano-scale particle size has not been investigated.

To generate nanocrystalline RDX a recrystallization process was developed based on rapid …

Removal And Recovery Of Fermentation-Produced Volatile Organic Compounds By A Novel Liquid Membrane-Based Pervaporation Technique, Atsawin Thongsukmak

Dissertations

Pervaporation is an energy -- efficient alternative to distillation for removing volatile organic compounds (VOCs) from water especially solvents from their dilute solutions in a fermentation broth. Liquid membranes have high selectivities for removing solvents from aqueous solutions compared with polymeric membranes or ceramic membranes; however liquid membranes have stability problems due to various losses. The loss of liquid membrane (LM) to the feed solution leads to toxicity for the organisms in a fermentation broth. A new liquid membrane based pervaporation technique has been developed to achieve high selectivity, ensure stability and prevent contamination of the fermentation broth. Trioctylamine (TOA) …

Experimental Investigation Of The Fluid Velocity Distribution In Stirred Tank Reactors Equipped With Retreat-Blade Impellers Using Laser Doppler Velocimetry, Deepak Rajesh Madhrani

Theses

Stirred tank reactors are commonly used in the pharmaceutical industry for synthesis of Active Pharmaceutical Ingredients (API's) and their intermediates. Typically, these vessels are glass-lined and are provided with a single retreat-blade glass-lined impeller and a single baffle. Despite their ubiquitous utilization in the pharmaceutical industry for at least the past 40 years, the mixing characteristics of these systems have not been studied to any great extent, making it difficult to predict mixing performance in any given operation.

In this work, the velocity distribution inside the typical glass-lined vessel/impeller system was experimentally quantified using Laser Doppler Velocimetry (LDV), which is …

The Effect Of Annealed Temperature On Properties Of Ru-Ir-Sn Oxide Anode Coatings, Lei Ji, Jun-Tao Wang, Li-Kun Xu, Wen-Bin Liu, Gui-Lin Xue

Journal of Electrochemistry

The anode coatings of Ru-Ir-Sn oxide were prepared by sol-gel method with different annealed temperatures.The influences of annealed temperature in properties of anode coatings were characterized by scanning electron microscope(SEM),energy dispersive X-ray detector(EDX),X-ray diffraction(XRD),potential of chlorine evolution,accelerated life,cyclic voltammetry and electrochemical impedance spectroscopy(EIS) tests.The results showed that the annealed temperature affected the morphology of coatings,while the electric quantities of cyclic voltammetry and double layer capacitances of anode coatings had a tendency to fall down and the potential of chlorine evolution and accelerated life had a tendency to increase as the annealed temperature increased.

Electrocatalytic Performance Of Pt/C And Pt/Wo3/C Catalysts For Methanol Oxidation, Yuan-Yuan Chu, Bing Wu, Ya-Wen Tang, Tian-Hong Lu, Ying Gao

Journal of Electrochemistry

The catalysts of Carbon supported Pt(Pt/C) and carbon supported Pt/WO₃(Pt/WO₃/C) were prepared with liquid phase reduction method.It was found that the catalytic activity and stability of the Pt/WO₃/C catalysts were increased with the addition of WO₃.When the atomic ratio of Pt and W was 1∶1,the best electrocatalytic performance of the Pt/WO₃/C catalyst for the methanol oxidation was obtained.This is attributed to the larger electrochemical surface area of Pt/WO₃/C and the weeker adsorption of CO towards the catalyst.

Nano-Polymeric Carrier Influences Ultrasonic Drug Delivery To Tumors, Odgerel Badamjav, Ghaleb A. Husseini, Peter Jones, William G. Pitt, Beverly L. Roeder

Faculty Publications

Our overall research goal is to alleviate the severe side effects of chemotherapy while enhancing the effectiveness of the treatment by localizing the delivery of anti-cancer drugs to the cancer tissue only. To this end we are synthesizing ultrasonically-activated delivery systems that can control drug delivery in space and time. Ultrasound (US) is non-invasive (no surgery required) and can be focused on the specific tissue to be treated. Our past research has developed a nano-sized polymeric drug carrier that sequesters the therapeutic drug, such as Doxorubicin (Dox), within the carrier and releases the drug upon insonation by ultrasound. This drug-containing …

Synthesis And Electrochemical Characteristics Of Li[Li(0.167)Mn(0.583)Ni(0.25)]O2 Cathode Material, Ling-Yan Yu, Wei-Hua Qiu, Fang Lian, Jia-Yuan Huang, Xao-Li Kang, Wei Liu

Journal of Electrochemistry

The cathode material of Li[Li_0.167Mn_0.583Ni_0.25]O₂ was synthesized by low-heat solid state reaction.The results of XRD and FESEM indicated that the powders of the material were well crystallized with the uniform diameters ranging from 60 nm to 100 nm and could be indexed as α-NaFeO₂ structure(R3-m space). Galvanostatic charge-discharge tests showed that the electrode delivered the capacity of about 120 mAh/g with good cyclability when cycled in 2.5~4.4V at 0.5C. When the cut-off potential was set up to 4.6V, the cathode delivered much larger capacities with the maximum of 234 mAh/g. It was …

Synthesis Of Agv3O8 As High-Capacity Of Cathode Materials For Lithium Secondary Batteries Via A Soft Chemistry Technique, Xiao-Yu Cao, Tao Li, Ling-Ling Xie, Xiang-Yang Yan, Chi-Wei Wang

Journal of Electrochemistry

The layered cathode material of AgV₃O₈ has been prepared for the lithium secondary batteries via the soft chemistry technique. The so-synthesized powders were characterized by XRD(powder X-ray diffraction), SEM(scanning electron microscope) and LPSA(laser particle size analysis). The electrochemical property was investigated by the galvanostatic discharge-charge technique. The results indicated that the particale sizes of AgV₃O₈ prepared were small in the distribution of narrow range, which leads to high discharge capacity. Among them, the material synthesized at 400 ℃ displayed the first discharge capacity of 760.5 mAh/g.

Electroless-Deposition Synthesis Of Highly Active Ptru/C And Ptrusn/C As Anode Catalysts For Defc, Jing Zhu, Yi Su, Hua Ma, Fang-Yi Cheng, Zhan-Liang Tao, Jing Liang, Jun Chen

Journal of Electrochemistry

In this paper,the preparation,characterization,and ethanol electrocatalytic oxidation of Pt_0.5Ru_0.5/C and Pt_0.5Ru_0.15Sn_0.35/C electrocatalysts were reported.The electroless-deposition with sensitization-activation pretreatment was applied to prepare Pt_0.5Ru_0.5/C and Pt_0.5Ru_0.15Sn_0.35/C electrocatalysts. The XRD and TEM analyses showed that the as-prepared catalysts were composed of well-dispersed PtRu or PtRuSn nanoparticles with an average particle size of about 3 nm.The electrochemical measurements demonstrated that the as-prepared Pt_0.5Ru_0.5/C and Pt_0.5Ru_0.15Sn_0.35/C catalysts exhibited much enhanced peak current density for …

Performance Of Air Breathing Direct Methanol Fuel Cell Under Ambient Condition, Jian-Guo Liu, Jun Gu, Tao Yu, Zhi-Gang Zou, T.S Zhao

Journal of Electrochemistry

The performance of the passive DMFC was systematically investigated under an ambient condition by simulating a wide range of temperature and humidity in a high-quality environmentally controlled room.The results indicated that the performance of the passive DMFC was nearly independent of ambient humidity from 30% to 90% RH and water produced in the cathode was expelled mostly from the cell in a liquid state.Compared with the humidity,the ambient temperature has a significant effect on the performance of the passive DMFC.The power density of 30 mW·cm^-2 were obtained at 40℃,while only 10 mW·cm^-2 at 10 ℃.

Sticky Gecko Feet: The Role Of Temperature And Humidity, Peter H. Niewiarowski, Stephanie Lopez, Liehui Ge, Emily Hagan, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

Gecko adhesion is expected to be temperature insensitive over the range of temperatures typically experienced by geckos. Previous work is limited and equivocal on whether this expectation holds. We tested the temperature dependence of adhesion in Tokay and Day geckos and found that clinging ability at 12 degrees C was nearly double the clinging ability at 32 degrees C. However, rather than confirming a simple temperature effect, our data reveal a complex interaction between temperature and humidity that can drive differences in adhesion by as much as two-fold. Our findings have important implications for inferences about the mechanisms underlying the …