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Full-Text Articles in Chemical Engineering

The Design And Optimization Of A Styrene Production Plant, Kaylee Hardenstein, Amanda Anderson May 2026

The Design And Optimization Of A Styrene Production Plant, Kaylee Hardenstein, Amanda Anderson

Honors Theses

This thesis presents the design and economic optimization of a Styrene Production Plant targeting a capacity of 100,000 tonnes/yr at a product purity of 99.8 wt%. The process relies on the dehydrogenation of ethylbenzene in a packed-bed reactor system. Downstream separation is achieved through a series of cooling, phase separation, and distillation operations to recover styrene while recycling unreacted ethylbenzene and recovering valuable byproducts.

A base case design was developed and evaluated using a process simulation software, Aspen Plus V14, and an economic analysis. Sensitivity analysis identified the styrene market price and ethylbenzene raw material cost as the dominant factors …


The Design And Manufacturing Process Of The Concealed Shelf, Mexrojiddinbek Sattorov May 2026

The Design And Manufacturing Process Of The Concealed Shelf, Mexrojiddinbek Sattorov

Honors Theses

This document contains information regarding the design and build process of the Concealed Shelf, which is a furniture product with hidden storage capability. First, the team members decided on the design of the product, followed by market analysis and manufacturing feasibility. Lean manufacturing principles were applied to improve the process efficiency and reduce waste.

Multiple prototypes were built with varying raw materials and locking mechanisms. Jigs and fixtures were handcrafted to ensure more consistent product quality. Two production runs were conducted to evaluate performance and identify areas for improvement.

The final design includes economic considerations, manufacturing layout, and continuous improvement …


Optimization And Dynamic Control Of Acetone Production From Isopropyl Alcohol, Thomas W. Wasson May 2026

Optimization And Dynamic Control Of Acetone Production From Isopropyl Alcohol, Thomas W. Wasson

Honors Theses

This paper investigates the optimization and dynamic control of acetone production via catalytic dehydrogenation of isopropyl alcohol. Optimization was conducted using steady-state Aspen Plus modeling with product specifications of 30,000 metric tons per year of 99.9% pure acetone by weight. Dynamic modeling of the feed preparation and reaction portions of the process was conducted in Aspen Plus Dynamic. Through optimization efforts the primary economic factor, net present value (NPV), was increased from $(126.6) million to $(83.2) million, representing a $43.4 million increase. This was primarily accomplished through a switch to low temperature catalyst, optimization of reactor dimensions, pressurization of key …


Deciphering Mechanochemical Influences Of Emergent Actomyosin Crosstalk Using Qcm‑D, Emily M. Kerivan, Victoria N. Amari, William B. Weeks, Leigh H. Hardin, Lyle Tobin, Omayma Y. Al Azzam, Dana N. Reinemann Dec 2024

Deciphering Mechanochemical Influences Of Emergent Actomyosin Crosstalk Using Qcm‑D, Emily M. Kerivan, Victoria N. Amari, William B. Weeks, Leigh H. Hardin, Lyle Tobin, Omayma Y. Al Azzam, Dana N. Reinemann

Faculty and Student Publications

Purpose: Cytoskeletal protein ensembles exhibit emergent mechanics where behavior in teams is not necessarily the sum of the components’ single molecule properties. In addition, filaments may act as force sensors that distribute feedback and influence motor protein behavior. To understand the design principles of such emergent mechanics, we developed an approach utilizing QCM-D to measure how actomyosin bundles respond mechanically to environmental variables that alter constituent myosin II motor behavior.

Methods: QCM-D is used for the first time to probe alterations in actin-myosin bundle viscoelasticity due to changes in skeletal myosin II concentration and motor nucleotide state. Actomyosin bundles were …


Collapse Of Pre-Covid-19 Differences In Performance In Online Vs. In-Person College Science Classes, And Continued Decline In Student Learning, Gregg R. Davidson, Hong Xiao, Kristin Davidson Nov 2024

Collapse Of Pre-Covid-19 Differences In Performance In Online Vs. In-Person College Science Classes, And Continued Decline In Student Learning, Gregg R. Davidson, Hong Xiao, Kristin Davidson

Faculty and Student Publications

Abstract: Studies comparing student outcomes for online vs. in-person classes have reported mixed results, though with a majority finding that lower-performing students, on average, fare worse in online classes, attributed to the lack of built-in structure provided by in-person instruction. The online/in-person outcome disparity was normative for non-major geology classes at the University of Mississippi prior to COVID-19, but the difference disappeared in the years after 2020. Previously distinct trendlines of GPA-based predictions of earned-grade for online and in-person classes merged. Of particular concern, outcomes for in-person classes declined to match pre-COVID-19 online expectations, with lower-GPA students disproportionally impacted. Objective …


Process Optimization Of An Ethylbenzene Production Facility Through Integrated Process Simulation And Economic Analysis Methods, Veronica Cunitz May 2024

Process Optimization Of An Ethylbenzene Production Facility Through Integrated Process Simulation And Economic Analysis Methods, Veronica Cunitz

Honors Theses

The following thesis consists of an investigation into the optimization of an ethylbenzene production facility. Aspen Plus software was used to model the production facility and Excel was used to price the facility using Aspen simulation data. This integrated technique was used to optimize the facility based on the Net Present Value (NPV) of the project. The NPV was improved from a base case value of -$23.5 million to a final value of $51.5 million. After this optimization based on NPV, the potential of operating the reactors as isothermal packed bed reactors was investigated. The reactor inlet feed pressure, inlet …


The Design And Optimization Of An Ethylbenzene Production Process, Alexander Koons May 2024

The Design And Optimization Of An Ethylbenzene Production Process, Alexander Koons

Honors Theses

Ethylbenzene is a foundational organic compound used as a reactant in styrene production. The objective of this thesis is to present the optimization of the in-house production process of ethylbenzene, aiming to avoid external procurement for the downstream styrene manufacturing facility. The process underlines a strategic approach to enhance the yield and cost efficiency of the production of ethylbenzene. An economic analysis revealed a promising net present value of approximately $57.6 million. This thesis not only proposes a viable route for internal ethylbenzene generation but also discusses optimizing the chemical production processes for enhanced efficiency and sustainability.


Synthesis And Analysis Of A Novel Magnetic Surfactant, Donovan Turpin May 2024

Synthesis And Analysis Of A Novel Magnetic Surfactant, Donovan Turpin

Honors Theses

Researchers in the University of Mississippi Chemical Engineering Department have suggested that chelation of a large magnetic transition metal, namely dysprosium, into the large polar head group of a surfactant could result in a magnetic surfactant. This project was aimed at synthesizing a surfactant with a large enough head group and negative charge (specifically EDTA) to support this ion and demonstrating that the chelation process was successful. If so, the molecule would ideally be capable of forming micelles which could extract oily substances from water using a strong magnet—possibly applicable to environmental crises like oil spills.

NMR analysis has suggested, …


Optimization Of Ethylbenzene Production Facility, Chance Ferrell May 2024

Optimization Of Ethylbenzene Production Facility, Chance Ferrell

Honors Theses

Ethylbenzene is a foundational organic compound used as a reactant in styrene production. The objective of this thesis is to present the optimization of the in-house production process of ethylbenzene, aiming to avoid external procurement for the downstream styrene manufacturing facility. The process underlines a strategic approach to enhance the yield and cost efficiency of the production of ethylbenzene. An economic analysis revealed a promising net present value of approximately $57.6 million. This thesis not only proposes a viable route for internal ethylbenzene generation but also discusses optimizing the chemical production processes for enhanced efficiency and sustainability.


The Biological Activity Of Dual-Responsive Glycopolymers For Intracellular Codelivery Of Antigen And Lipophilic Adjuvant, Micaela Shields May 2023

The Biological Activity Of Dual-Responsive Glycopolymers For Intracellular Codelivery Of Antigen And Lipophilic Adjuvant, Micaela Shields

Honors Theses

Subunit vaccines present themselves as an attractive alternative to traditional approaches to vaccines, which utilizes whole organisms to trigger an immune response. While these traditional approaches have proven themselves reliable within the history of vaccinations, they generally deliver subpar robust cellular-mediated immunity and pose many safety risks. Composed of proteins and /or peptides, subunit vaccines are safer and more precise alternatives to traditional approaches. However, the pharmacokinetic properties of the macromolecules that make up these vaccines hinder the subunit vaccine’s level of immunogenicity [d1] Examples of this hindrance include but are not limited to aggregation at the injection site and …


Development Of Novel Sensor Coating Methodology To Enable Understanding Of Fouling Mechanisms On Ion Exchange Membranes, Andrew Ulmer May 2023

Development Of Novel Sensor Coating Methodology To Enable Understanding Of Fouling Mechanisms On Ion Exchange Membranes, Andrew Ulmer

Honors Theses

As populations expand and natural water resources are depleted, severe droughts and limited access to clean water have become an increased threat to areas across the world. Effective and economic water treatment methods such as electrodialysis (ED) are vital for combating these threats, especially in developing nations and secluded locations. Organic foulant adsorption on the surface of ion exchange membranes severely limits the capabilities of water desalination systems such as ED along with significantly increasing maintenance costs. Understanding characteristics such as the total amount and rate at which these foulants at specific concentrations adsorb and desorb to the membranes is …


An Analysis Of The Production Of Pharmaceutical-Grade Acetone Via The Dehydrogenation Of Isopropanol (Ipa), Jordan Desplas May 2023

An Analysis Of The Production Of Pharmaceutical-Grade Acetone Via The Dehydrogenation Of Isopropanol (Ipa), Jordan Desplas

Honors Theses

The production of 99.9 wt% acetone from isopropanol in Unit 1100 is designed to start up in 2025 and operate for 12 years after startup. The engineering team was tasked with designing the process, creating an economic model, and optimizing the net present value (NPV). The process was simulated in AVEVA PRO/II Simulation for the design process, and the economic analysis was estimated in Microsoft Excel. Parametric and topological optimization was performed linearly on the unit operations in the process. The NPV was improved by $14M from a base case of $122M to an optimized case of $136M. The project …


Optimization Of A Fluidized Bed Reactor For The Production Of Acetone From Isopropyl Alcohol, Andrew Rawls Wasson May 2023

Optimization Of A Fluidized Bed Reactor For The Production Of Acetone From Isopropyl Alcohol, Andrew Rawls Wasson

Honors Theses

For the optimization of the isopropyl alcohol to acetone process, Unit 1100, the Net Present Value (NPV) was used as the objective function to observe the economic impact of each of the optimization factors being tested. During the optimization process, it is not only important to optimize the process’s profitability but also to ensure that the process operates efficiently and meets product specifications. The goal of this optimization was to alter variables from the base case calculations of Unit 1100 to maximize the NPV of the unit. AVEVA ProII software was used to simulate the process and make changes to …


The Design Estimate Of A Warehouse Refrigeration System, Jackson Dear May 2023

The Design Estimate Of A Warehouse Refrigeration System, Jackson Dear

Honors Theses

The intention of this project was to provide a design and cost estimate for the refrigeration systems within an industrial cold storage distribution center for Magnolia Country Frozen Foods, Inc. in East Rutherford, NJ. The facility includes eighteen 300,000 ft3 units (200 ft x 100 ft x 15 ft). These units require 200 tons of refrigeration at a maintained temperature of 0oF. This project's scope included choosing an optimal refrigeration system, selecting a refrigerant for use within the system, and providing a cost estimate for the purchase of the refrigeration system equipment and for the yearly cost associated with running …


Investigating Myosin Ensemble Force Generation Using Optical Tweezers, Janie Watts Apr 2023

Investigating Myosin Ensemble Force Generation Using Optical Tweezers, Janie Watts

Honors Theses

Myosin is a motor protein that facilitates muscle contraction and movement by stepping along actin filaments using energy from ATP hydrolysis. If myosin or other motors are disrupted throughout the body, it can have many harmful effects. Hypertrophic cardiomyopathy is a disease caused by gene mutations that affect myosin heavy chains in the heart. The tissue of the heart becomes abnormally thick, which can make it more difficult to pump blood or block blood flow out of the heart. Our goal is to discern the mechanistic difference function of a healthy and diseased heart. To accomplish this, we construct model …


Molecular And Cellular Level Characterization Of Cytoskeletal Mechanics Using A Quartz Crystal Microbalance, Emily M. Kerivan, Lyle Tobin, Mihir Basil, Dana N. Reinemann Mar 2023

Molecular And Cellular Level Characterization Of Cytoskeletal Mechanics Using A Quartz Crystal Microbalance, Emily M. Kerivan, Lyle Tobin, Mihir Basil, Dana N. Reinemann

Faculty and Student Publications

A quartz crystal microbalance (QCM) is an instrument that has the ability to measure nanogram-level changes in mass on a quartz sensor and is traditionally used to probe surface interactions and assembly kinetics of synthetic systems. The addition of dissipation monitoring (QCM-D) facilitates the study of viscoelastic systems, such as those relevant to molecular and cellular mechanics. Due to real-time recording of frequency and dissipation changes and single protein-level precision, the QCM-D is effective in interrogating the viscoelastic properties of cell surfaces and in vitro cellular components. However, few studies focus on the application of this instrument to cytoskeletal systems, …


Myosin Ii Adjusts Motility Properties And Regulates Force Production Based On Motor Environment, Omayma Y. Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann Aug 2022

Myosin Ii Adjusts Motility Properties And Regulates Force Production Based On Motor Environment, Omayma Y. Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann

Faculty and Student Publications

Introduction—Myosin II has been investigated with optical trapping, but single motor-filament assay arrangements are not reflective of the complex cellular environment. To understand how myosin interactions propagate up in scale to accomplish system force generation, we devised a novel actomyosin ensemble optical trapping assay that reflects the hierarchy and compliancy of a physiological environment and is modular for interrogating force effectors.

Methods—Hierarchical actomyosin bundles were formed in vitro. Fluorescent template and cargo actin filaments (AF) were assembled in a flow cell and bundled by myosin. Beads were added in the presence of ATP to bind the cargo AF …


Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana May 2022

Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana

Honors Theses

There is a high demand of energy for generating civil applicable power in the world and in the USA, correspondingly. The world has been consuming various sources to extract the power to meet its demands. Most of the power sources include renewable and non-renewable sources like fossil fuels, natural gas, coal, water, solar, wind, and nuclear power. Although most of these sources have many advantages in terms of their capacity and cost of production, nuclear power can be categorized as the emerging driving force in the United States and in the world for power generation, because of its reliability and …


Optimization Of An Ethylbenzene To Styrene Production Facility, John Michels May 2022

Optimization Of An Ethylbenzene To Styrene Production Facility, John Michels

Honors Theses

The purpose of this case study is to optimize the design and production of an ethylbenzene-to-styrene manufacturing facility, Unit 500. Compared to the original base-case design, the optimizations presented in this document will save approximately $337 million dollars without compromising the production requirements or quality. Optimization of this process used net present value as an objective function, with changes centered around the reactors, but also the separation equipment and exchangers prior to separation, as those devices most directly controlled process stream contents and conditions. The second set of reactors was removed in favor of using one optimized set of reactors, …


Optimization And Analysis Of A Styrene Production Process, Alexis Kimpel May 2022

Optimization And Analysis Of A Styrene Production Process, Alexis Kimpel

Honors Theses

The production of styrene from ethylbenzene in Unit 500 is designed to start up in 2024 and operate for 12 years after startup. The engineering team was tasked with designing the process, creating an economic model, and optimizing the net present value (NPV). The process was simulated in AVEVA PRO/II Simulation for the design process and to estimate the size of equipment. Parametric and topological optimization was performed subsequently on the unit operations in the process. The NPV was improved by $423M from a base case of -$919M to an optimized case of -$496M. The project is recommended to continue …


Optimization Of Styrene From Ethylbenzene Case Study, Jabria Daria Thompson May 2022

Optimization Of Styrene From Ethylbenzene Case Study, Jabria Daria Thompson

Honors Theses

The following pages detail the optimization process of styrene from ethylbenzene in the Styrene Production Plant, Unit 500. There were two parts of the assignment, each with slightly different end goals. The goal of the first part of the assignment, was to create a process that would effectively and efficiently increase the negative Net Present Value (NPV) of the production plant. Procedures taken in this process included developing a working kinetic process simulation model and optimizing this model through unit operations and heat integration, as well as developing an accurate economic model that will be used to evaluate the proposed …


The Design And Economic Optimization Of A Warehouse Refrigeration System, Hannah Talbot May 2022

The Design And Economic Optimization Of A Warehouse Refrigeration System, Hannah Talbot

Honors Theses

The purpose of this project was to design a cool warehouse refrigeration system for Acme Frozen Foods, Inc located in Newark, New Jersey. The refrigeration system was used to cool eighteen 300,000 ft3 refrigerated units (200 ft x 100 ft x 15 ft), each requiring 200 cooling tons of refrigeration at a level of 0 F. The scope of this project included determining the appropriate refrigeration cycle, selecting the most desirable refrigerant, and temperature ranges to optimize the performance of the system. This project also considered the economic cost of the power needed to run the refrigerated units and …


Optimization Of A Styrene Prodcution And Separation Process, Bryce Little May 2022

Optimization Of A Styrene Prodcution And Separation Process, Bryce Little

Honors Theses

A step wise optimization of Unit 500 was completed. Unit 500 is a planned ethylbenzene to styrene production plant that has a annual production goal of 100,000 metric tons of styrene. The cost of styrene on the market is $1,598. The base case of Unit 500 produced styrene at a cost of $2,650. Optimization was completed with an emphasis on parametric changes though material of construction and heat integration were also considered. The optimized Unit 500 design reduced the cost of styrene production to $2,035 per metric ton. While this represents a significant improvement on the base case cost, it …


Probing Myosin Ensemble Mechanics In Actin Filament Bundles Using Optical Tweezers, Omayma Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann May 2022

Probing Myosin Ensemble Mechanics In Actin Filament Bundles Using Optical Tweezers, Omayma Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann

Faculty and Student Publications

Myosins are motor proteins that hydrolyze ATP to step along actin filament (AF) tracks and are essential in cellular processes such as motility and muscle contraction. To understand their force-generating mechanisms, myosin II has been investigated both at the single-molecule (SM) level and as teams of motors in vitro using biophysical methods such as optical trapping. These studies showed that myosin force-generating behavior can differ greatly when moving from the single-molecule level in a three-bead arrangement to groups of motors working together on a rigid bead or coverslip surface in a gliding arrangement. However, these assay constructions do not permit …


Optimization Of A Fluidized Bed Reactor For The Production Of Styrene From Ethylbenzene, Gregory Espenan May 2022

Optimization Of A Fluidized Bed Reactor For The Production Of Styrene From Ethylbenzene, Gregory Espenan

Honors Theses

In order to optimize Unit 500, a styrene production plant, the Net Present Value (NPV) was used as the objective function to ensure every optimization strategy had a positive economic effect. To optimize a chemical plant, it is important to note efficiency, economics, product specifications, and production requirements. The goal of this project was to make changes to the base case of Unit 500 to minimize the cost to produce styrene for an upstream unit. PRO/II was used to simulate various points in different unit operations throughout the process. The NPV was measured after each unit operation was simulated to …


A Proper Framework For Studying Noise From Jets With Non-Compact Sources, Woutijn J. Baars, Nathan E. Murray, Charles E. Tinney Dec 2021

A Proper Framework For Studying Noise From Jets With Non-Compact Sources, Woutijn J. Baars, Nathan E. Murray, Charles E. Tinney

Faculty and Student Publications

A quantitative assessment of the acoustic source field produced by a laboratory-scale heated jet with a gas dynamic Mach number of 1.55 and an acoustic Mach number of 2.41 is performed using arrays of microphones that are traversed across the axial and radial plane of the jet's acoustic field. The nozzle contour comprises a method of characteristics shape so that shock-related noise is minimal and the dominant sound production mechanism is from Mach waves. The spatial topography of the overall sound pressure level is shown to be dominated by a distinct lobe residing on the principal acoustic emission path, which …


Metasurface Cloaks To Decouple Closely Spaced Printed Dipole Antenna Arrays Fed By A Microstrip-To-Balanced Transmission-Line Transition, Doojin Lee, Alexander B. Yakovlev Sep 2021

Metasurface Cloaks To Decouple Closely Spaced Printed Dipole Antenna Arrays Fed By A Microstrip-To-Balanced Transmission-Line Transition, Doojin Lee, Alexander B. Yakovlev

Faculty and Student Publications

In this work, we present a numerical study of 1D and 2D closely spaced antenna arrays of microstrip dipole antennas covered by a metasurface in order to properly cloak and decouple the antenna arrays operating at neighboring frequencies. We show that the two strongly coupled arrays fed by a microstrip-to-balanced transmission-line transition are effectively decoupled in 1D and 2D array scenarios by covering the dipole antenna elements with an elliptically shaped metasurface. The metasurface comprises sub-wavelength periodic metallic strips printed on an elliptically shaped dielectric cover around the dipole antennas and integrated with the substrate. We present a practical design …


Heteroacene-Based Amphiphile As A Molecular Scaffold For Bioimaging Probes, Tharindu A. Ranathunge, Mahesh Loku Yaddehige, Jordan H. Varma, Cameron Smith, Jay Nguyen, Iyanuoluwani Owolabi, Wojciech Kolodziejczyk, Nathan I. Hammer, Glake Hill, Alex Flynt, Davita L. Watkins Aug 2021

Heteroacene-Based Amphiphile As A Molecular Scaffold For Bioimaging Probes, Tharindu A. Ranathunge, Mahesh Loku Yaddehige, Jordan H. Varma, Cameron Smith, Jay Nguyen, Iyanuoluwani Owolabi, Wojciech Kolodziejczyk, Nathan I. Hammer, Glake Hill, Alex Flynt, Davita L. Watkins

Faculty and Student Publications

The challenges faced with current fluorescence imaging agents have motivated us to study two nanostructures based on a hydrophobic dye, 6H-pyrrolo[3,2-b:4,5-b’]bis [1,4]benzothiazine (TRPZ). TRPZ is a heteroacene with a rigid, pi-conjugated structure, multiple reactive sites, and unique spectroscopic properties. Here we coupled TRPZ to a tert-butyl carbamate (BOC) protected 2,2-bis(hydroxymethyl)propanoic acid (bisMPA) dendron via azide-alkyne Huisgen cycloaddition. Deprotection of the protected amine groups on the dendron afforded a cationic terminated amphiphile, TRPZ-bisMPA. TRPZ-bisMPA was nanoprecipitated into water to obtain nanoparticles (NPs) with a hydrodynamic radius that was comparison, TRPZ-PG was encapsulated in pluronic-F127 (Mw = 12 kD), a polymer surfactant …


Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis May 2021

Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis

Honors Theses

Our team entered the 2021 AVEVA Academic Competition, where teams of undergraduate senior chemical engineering students competed across the country. The competition was composed of two parts: the base case design and the optimization of a chemical process. As part of the competition, our team is acting as the Engineering team for a fictional company that has given us this project. Due to COVID-19, our methanol producing company has lost a contract with a customer, leaving 23,000 tonnes/yr of unclaimed methanol. We have two choices with this methanol: either sell the methanol on the market at the spot price for …


Ethylbenzene Production Case Study And Optimization, Brandon Borek May 2021

Ethylbenzene Production Case Study And Optimization, Brandon Borek

Honors Theses

The objective of this project was to investigate the process of producing ethylbenzene from the liquid-phase reaction of ethylene and benzene and perform parametric and topological optimizations to increase the net present value of the production facility. To do so, the base case conditions of the process were modeled and quantified economically followed by an investigation into the existing process to determine conditions that could be altered to improve the economic viability of the project. After optimizing the parametric conditions and topology of the process, the net present value of the project was increased by 305 million dollars to 191 …