Chemical Engineering Commons^™

Investigation Of The Use Of A Plasticizer-Polymer Sensor Coating With Improved Long-Term Stability In The Liquid Phase, Laura Jeanne Alderson

Master's Theses (2009 -)

Benzene is one of the volatile organic compounds present in crude oil and gasoline. Leakage from underground storage tanks or hazardous waste sites can introduce benzene contamination into nearby groundwater. Benzene is a known carcinogen and its exposure is limited by the Environmental Protection Agency to 5 parts per billion (ppb) in drinking water. Early, accurate detection of the presence of benzene contamination in groundwater supplies is extremely important. Shear horizontal surface acoustic wave (SH-SAW) devices with a chemically sensitive coating can be used for the detection of volatile organic compounds in liquid, such as BTEX (benzene, toluene, ethylbenzene and …

Closing A Synthetic Carbon Cycle: Carbon Dioxide Conversion To Carbon Monoxide For Liquid Fuels Synthesis, Yolanda Andreina Daza

USF Tampa Graduate Theses and Dissertations

CO₂ global emissions exceed 30 Giga tonnes (Gt) per year, and the high atmospheric concentrations are detrimental to the environment. In spite of efforts to decrease emissions by sequestration (carbon capture and storage) and repurposing (use in fine chemicals synthesis and oil extraction), more than 98% of CO₂ generated is released to the atmosphere. With emissions expected to increase, transforming CO₂ to chemicals of high demand could be an alternative to decrease its atmospheric concentration. Transportation fuels represent 26% of the global energy consumption, making it an ideal end product that could match the scale of CO …

Early Acidification Of Mars And The Potential Implications For Biology, Sarah Stewart Johnson, D. Goerlitz, Kathleen C. Benison, Melanie R. Mormile, D. W. Ming

Biological Sciences Faculty Research & Creative Works

A leading paleoclimate theory for Mars, based on the identification of phyllosilicate minerals in ancient terrains, posits that the first several million years of the planet’s history were dominated by neutral to alkaline pH. However, evidence is mounting for the consideration of an alternate hypothesis: that some smectites on Mars formed under acidic conditions, and that the early surface of Mars may not have been subject to circum-neutral pH conditions, at least not uniformly. Work on shergottitic liquids suggests that up to 2400 ppm of sulfur could have degassed from martian magma, supplying more than enough sulfur for the planet’s …

Conversion Of Landfill Gas To Liquid Hydrocarbon Fuels: Design And Feasibility Study, Ryan Alexander Kent

USF Tampa Graduate Theses and Dissertations

This paper will discuss the conversion of gas produced from biomass into liquid fuel through the combination of naturally occurring processes, which occur in landfills and anaerobic digesters, and a gas-to-liquids (GTL) facility. Landfills and anaerobic digesters produce gases (LFG) that can be converted into syngas via a Tri-reforming process and then synthesized into man-made hydrocarbon mixtures using Fischer-Tropsch synthesis. Further processing allows for the separation into liquid hydrocarbon fuels such as diesel and gasoline, as well as other middle distillate fuels. Conversion of landfill gas into liquid fuels increases their energy density, ease of storage, and open market potential …

A Continuous Formulation For Logical Decisions In Differential Algebraic Systems Using Mathematical Programs Of Complementarity Constraints, Kody Powell, Ammon N. Eaton, John Hedengren, Thomas F. Edgar

Faculty Publications

This work presents a methodology to represent logical decisions in differential algebraic equation simulation and constrained optimization problems using a set of continuous algebraic equations. The formulations may be used when state variables trigger a change in process dynamics, and introduces a pseudo-binary decision variable, which is continuous, but should only have valid solutions at values of either zero or one within a finite time horizon. This formulation enables dynamic optimization problems with logical disjunctions to be solved by simultaneous solution methods without using methods such as mixed integer programming. Several case studies are given to illustrate the value of …

A Continuous Formulation For Logical Decisions In Differential Algebraic Systems Using Mathematical Programs With Complementarity Constraints, Kody M. Powell, Ammon N. Eaton, John Hedengren, Thomas F. Edgar

Faculty Publications

This work presents a methodology to represent logical decisions in differential algebraic equation simulation and constrained optimization problems using a set of continuous algebraic equations. The formulations may be used when state variables trigger a change in process dynamics, and introduces a pseudo-binary decision variable, which is continuous, but should only have valid solutions at values of either zero or one within a finite time horizon. This formulation enables dynamic optimization problems with logical disjunctions to be solved by simultaneous solution methods without using methods such as mixed integer programming. Several case studies are given to illustrate the value of …

Modified Yttrium Hydroxide/Mc Nylon Nanocomposites And Scaling Effects In Multilayer Polyethylene Films, Jia Chen

USF Tampa Graduate Theses and Dissertations

In this thesis, monomer casting (MC) nylon was synthesized. MC nylon could replace nonferrous metals in certain applications, including gears, wheels, and other moving parts. However, compared with metals, MC nylon products have poor strength and stiffness, and crack easily, especially at low temperatures. In addition, the dimensional stability of MC nylon is poor, especially in the large casting nylon products, causing significant internal stresses due to shrinkage. Thus, MC nylon cracks easily when cast and molded. The yttrium hydroxide particles were modified by stearic acid and dispersed in the caprolactam. The polymerization time was short due to fast anionic …

Pathways To Ultra-Low Platinum Group Metal Catalyst Loading In Proton Exchange Membrane Electrolyzers, Julie N. Renner

Faculty Scholarship

Hydrogen is one of the world's most important chemicals, with global production of about 50 billion kg/year. Currently, hydrogen is mainly produced from fossil fuels such as natural gas and coal, producing CO2. Water electrolysis is a promising technology for fossil-free, CO2-free hydrogen production. Proton exchange membrane (PEM)-based water electrolysis also eliminates the need for caustic electrolyte, and has been proven at megawatt scale. However, a major cost driver is the electrode, specifically the cost of electrocatalysts used to improve the reaction efficiency, which are applied at high loadings (>3 mg/cm2 total platinum group metal (PGM) content). Core-shell catalysts …

Large-Area Graphene-Based Nanofiltration Membranes By Shear Alignment Of Discotic Nematic Liquid Crystals Of Graphene Oxide, Abozar Akbari, Phillip Sheath, Samuel T. Martin, Dhanraj B. Shinde, Mahdokht Shaibani, Parama Chakraborty Banerjee, Rachel Tkacz, Dibakar Bhattacharyya, Mainak Majumder

Chemical and Materials Engineering Faculty Publications

Graphene-based membranes demonstrating ultrafast water transport, precise molecular sieving of gas and solvated molecules shows great promise as novel separation platforms; however, scale-up of these membranes to large-areas remains an unresolved problem. Here we demonstrate that the discotic nematic phase of graphene oxide (GO) can be shear aligned to form highly ordered, continuous, thin films of multi-layered GO on a support membrane by an industrially adaptable method to produce large-area membranes (13 × 14 cm²) in < 5 s. Pressure driven transport data demonstrate high retention (> 90%) for charged and uncharged organic probe molecules with a hydrated radius above 5 Å as well as modest (30–40%) retention of …

Biopolymeric Mucin And Synthetic Polymer Analogs: Their Structure, Function And Role In Biomedical Applications, Sundar Prasanth Authimoolam, Thomas D. Dziubla

Chemical and Materials Engineering Faculty Publications

Mucin networks are viscoelastic fibrillar aggregates formed through the complex self-association of biopolymeric glycoprotein chains. The networks form a lubricious, hydrated protective shield along epithelial regions within the human body. The critical role played by mucin networks in impacting the transport properties of biofunctional molecules (e.g., biogenic molecules, probes, nanoparticles), and its effect on bioavailability are well described in the literature. An alternate perspective is provided in this paper, presenting mucin’s complex network structure, and its interdependent functional characteristics in human physiology. We highlight the recent advances that were achieved through the use of mucin in diverse areas of bioengineering …

High Temperature Electrochemical Engineering And Clean Energy Systems, Brenda L. Garcia-Diaz, Luke Olson, Michael Martinez-Rodriguez, Roderick Fuentes, Hector Colon-Mercado, Josh Gray

Journal of the South Carolina Academy of Science

Global power demand is projected to more than double by 2050 and meeting this increased power demand will require maintaining or increasing power output from all existing energy sources while adding a large amount of new capacity. The power sources that have the greatest opportunity to fulfill this demand gap over this time period are clean energy sources including solar and nuclear power. One of the areas of expertise that SRNL has been applying to help with a variety of clean energy technologies is in high temperature electrochemistry. Savannah River National Laboratory (SRNL) in collaboration with industrial and university partners …

Mechanical Dispersion Of Semi-Solid Binders In High-Shear Granulation, Nathan J. Davis

Open Access Dissertations

Granulation is an important industrial process used to produce many foods, medicines, consumer products, and industrial intermediate products. This thesis focuses on high shear wet granulation with the specific case study of detergent manufacture using a high shear pin mixer. The key rate process in detergent manufacturing was determined to be the mechanical dispersion of the semi-solid surfactant binder. The pin mixer and mechanical dispersion utilized experiments, population balance models, and discrete element method (DEM) models.

The mechanical dispersion of the surfactant binder was studied using a lab scale 6 liter pin mixer. An experimental method was developed to isolate …

Extracellular Matrix From Whole Porcine Heart Decellularization For Cardiac Tissue Engineering, Nima Momtahan

Theses and Dissertations

Heart failure is one of the leading causes of death in the United States. Every year in the United States, more than 800,000 people are diagnosed with heart failure and more than 375,000 people die from heart disease. Current therapies such as heart transplants and bioartificial hearts are helpful, but not optimal. Decellularization of porcine whole hearts followed by recellularization with patient-specific human cells may provide the ultimate solution for patients with heart failure. Great progress has been made in the development of efficient processes for decellularization, and the design of automated bioreactors. In this study, the decellularization of porcine …

Aminoacyl-Trna Synthetase Production For Unnatural Amino Acid Incorporation And Preservation Of Linear Expression Templates In Cell-Free Protein Synthesis Reactions, Andrew Broadbent

Theses and Dissertations

Proteins—polymers of amino acids—are a major class of biomolecules whose myriad functions facilitate many crucial biological processes. Accordingly, human control over these biological processes depends upon the ability to study, produce, and modify proteins. One innovative tool for accomplishing these aims is cell-free protein synthesis (CFPS). This technique, rather than using living cells to make protein, simply extracts the cells' natural protein-making machinery and then uses it to produce protein in vitro. Because living cells are no longer involved, scientists can freely adapt the protein production environment in ways not otherwise possible. However, improved versatility and yield of CFPS protein …

Thawing Out: The Role Of The Arctic Council Service In A Melting Arctic, Taylor J. Enos

Pell Scholars and Senior Theses

With the changing natural and political climate of the Arctic, conflicts over resource extraction and navigation will become inevitable. Empowering an intergovernmental institution like the Arctic Council Service may be the only solution. This paper analyzes the importance and history of the Arctic as a political environment, which is prone to abuse in the very near future at the hands of Russia and the United States.

Oil Recovery By Flooding; Sensitivity Analysis To Technical Parameters, Rana Osama Fahmi Saqer

Theses

Numerous enhanced oil recovery techniques including miscible gas injection, chemical, thermal and other methods are applied at the third phase of production after both primary and secondary recovery have been exhausted. Polymer flooding is one of the chemical methods that recover more oil by decreasing the mobility of the system; by increasing the viscosity of the injected water that results in an improvement in the volumetric sweep efficiency.

The objective of this work is to asses and select the development options using polymer process that maximize oil recovery for a synthetic reservoir model where technical parameters are optimized thoroughly.

Reservoir …

Oil Recovery By Polymer Flooding; Sensitivity Analysis To Technical Parameters, Rana Osama Fahmi Saqer

Theses

Numerous enhanced oil recovery techniques including miscible gas injection, chemical, thermal and other methods are applied at the third phase of production after both primary and secondary recovery have been exhausted. Polymer flooding is one of the chemical methods that recover more oil by decreasing the mobility of the system; by increasing the viscosity of the injected water that results in an improvement in the volumetric sweep efficiency.

The objective of this work is to asses and select the development options using polymer process that maximize oil recovery for a synthetic reservoir model where technical parameters are optimized thoroughly.

Reservoir …

Contact Angle And Ift Measurements Of Smart Water At Elevated Temperatures And Pressures For Evaluating Wettability In A Selected Carbonate Reservoir In The Uae, Jassim Abubacker Ponnambathayil

Theses

Water flooding has been regarded as a well-known secondary oil recovery method. In the recent years, extensive research on crude oil, brine, and rock systems has acknowledged that the composition of the injected water can change wetting properties of the reservoir during a water flood in a promising way to improve oil recovery. Hence, injection of “smart water” with correct salinity and composition is considered as a tertiary recovery method. The mechanism behind wettability alteration that is promoted by smart water injection has been a topic of discussion in carbonate and sandstone formations. In this work, some key properties of …

Silk-Derived Graphene-Like Carbon With High Electrocatalytic Activity For Oxygen Reduction Reaction, Qingfa Wang, Ruoping Yanzhang, Yaqing Wu, Han Zhu, Junfeng Zhang, Mingliang Du, Ming Zhang, Li Wang, Xiangwen Zhang, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

A facile method to prepare the nanoporous and graphene-like carbon material from a natural silk fiber was developed by a potassium intercalation and carbonization procedure. The as-synthesized graphene-like fiber was employed for oxygen reduction reaction and exhibited impressive electrocatalytic activity.

Influence Of Strong Preformed Particle Gels On Low Permeable Formations In Mature Reservoirs, Mahmoud O. Elsharafi, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In mature reservoirs, the success of preformed particle gel (PPG) treatment rests primarily on the ability of the PPG to reduce and/or plug the high permeable formations but not damage the low permeable formations. Static test models (filtration test model and pressure test model) were used to determine the effect of PPG on low permeable formations. This work used a strong preformed particle gel, Daqing (DQ) gel made by a Chinese company. The particle gel sizes were ranged from 30 to 120 mesh for this work. PPGs are sized in a millimeter or micrometer, which can absorb over a hundred …