Digital Commons Network^™

In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson

Electronic Thesis and Dissertation Repository

Long Fiber Thermoplastics (LFT) are promising new materials with high physical properties and low density. These high properties are obtained by embedding very long fibers (~100 mm) into a thermoplastic matrix. Such a high fiber length dictates the use of a compression molding process for manufacturing as the length of discontinuous fibers in injection molding is limited by pellet length.

LFT composites are of great interest for the automotive industry. These materials are already used in some interior and exterior car parts such as bumpers, seat structures, door module etc. This research is inspired by the desire to manufacture load …

Sulfur Species Selective Adsorption Using A New Offretite Based Additive, Yira Yorsirys Aponte Torrealba

Electronic Thesis and Dissertation Repository

Fluid Catalytic Cracking (FCC) unit is one of the most important conversion processes used in petroleum refineries. Nowadays, petroleum refineries, and specifically FCC units, have to be improved. New technologies must be developed to increase the refineries revenues as well to comply with environmental regulations. One area of significant concern is the necessary in-situ FCC gasoline sulfur reduction.

In this respect, this PhD dissertation proposes a new Zn-Offretite (Zn-OFF) additive for gasoline sulfur reduction via selective adsorption in FCC units. The PhD research developed covers the preparation of the Zn-OFF zeolites and their physicochemical characterization. This physicochemical …

Co-Substrate Fermentation Of Jerusalem Artichoke Tubers And Crude Glycerol To Butanol With Integrated Product Recovery, Tahereh Sarchami

Electronic Thesis and Dissertation Repository

Butanol has long been considered a potential advanced liquid biofuel, in addition to its current application as an industrial solvent. It can be produced biologically; however, the conventional ABE fermentation suffers from many limitations, including low butanol titer, high cost of traditional raw materials, end-product inhibition and high butanol recovery costs. Possible solutions are the use of renewable low-cost feedstocks, genetic manipulations of Clostridia spp. to improve the strains’ butanol titer and tolerance, advanced fermentation techniques, and in-situ product recovery technologies.

In order to overcome some of these limitations, the overall goal of this thesis was to develop a process …

The Effects Of Furfural On Biological Hydrogen Production In Batch And Microbial Electrolysis Cell, Hyeongu Yeo

Electronic Thesis and Dissertation Repository

Furfural inhibits biohydrogen production and numerous studies has been carried out on detoxification of furfural to enhance biofuel production. Electrochemical detoxification of furfural is a new approach to remove furfural without the degradation of sugars. However, there is limited information on the effects of the degradation products of furfural on biohydrogen production in batch tests and the impact of furfural on anode-respiring bacteria (ARB) in microbial electrolysis cells (MECs). This study investigated the effect of furfural and its derivatives, furfuryl alcohol (FFA) and 2-furoic acid (FA), on biohydrogen production. The impact of furfural on hydrogen production in MECs was also …

Development Of Ultrasonic Techniques For Characterization Of Liquid Mixtures, William A. Cooke

Electronic Thesis and Dissertation Repository

To evaluate the suitability of ultrasonic techniques for on-line process monitoring applications, an ultrasonic probe was used to measure acoustic velocity, acoustic impedance, and isentropic compressibility of hydrocarbons (including n-, iso-, and cycloalkanes, toluene, mineral oil, and crude oil) and polar liquids (alcohols, water, salt water) over a temperature range of 25-60°C. Temperature, carbon chain length, molecular shape, and intermolecular forces had significant effects on ultrasonic parameters. Relationships between media characteristics and observed ultrasonic parameters were modeled using empirical-least squares equations. The same parameters were measured in binary mixtures of hydrocarbons in heptane, as well as polar liquids in ethanol. …

Agglomerate Formation And Heat Transfer Study In A Novel Mechanically Fluidized Reactor, Dhiraj M. Kankariya

Electronic Thesis and Dissertation Repository

The aim of the thesis was to study two important features of the Mechanically Fluidized Reactor (MFR): the good distribution of injected liquid on fluidized particles and the high heat transfer rate from the heated wall to the bed. Multiple industrial processes use liquid injection in fluidized bed reactors. The liquid distribution in the reactor should be efficient to minimize bed defluidization and to maximize the yield and quality of the products.

The study used two MFR units, with internal volumes of 1.0 and 4.42 litre, respectively. Induction heating was used to rapidly heat the bed, which is a unique …

Effect Of Local Bed Hydrodynamics On The Distribution Of Liquid In A Fluidized Bed, Lingchao Li

Electronic Thesis and Dissertation Repository

In an industrial Fluid CokerTM, liquid bitumen is injected into a bed of hot coke particles through spray nozzles, grouped in several banks at different vertical positions. The main objective of this thesis is to determine whether significant improvements in liquid-solid contact could be achieved by optimizing the location of the spray nozzles. In the coker regions where bitumen is injected, the gas is a mixture of product vapors and steam. Steam introduced at different levels rises through the coker: the stripping steam is injected near the bottom, then the attrition steam above the stripper and finally the bitumen atomization …

Fabrication And Cross-Linking Of L-Aspartic Acid Functionalized Poly(Ester Amide)-Based Tissue Engineering Scaffolds, Shuyu Liu

Electronic Thesis and Dissertation Repository

Scaffold fabrication is essential in tissue engineering. Amino acid based poly(ester amide)s (PEAs) have been investigated as scaffold materials due to their non-toxic degradation byproducts, and easily tunable mechanical and biological properties. However, L-aspartic acid functionalized PEAs showed poor morphological stability when immersed in buffer. This work focuses on the further functionalization of L-aspartic acid based PEAs, scaffold fabrication and cross-linking of the scaffold to improve morphological stability. Photo-cross-linkable and thermally cross-linkable PEAs were synthesized successfully and characterized. Two scaffold fabrication methods were applied: 1) electrospinning was applied to photo-cross-linkable PEAs, followed by UV treatment to cross-link electrospun scaffolds; 2) …

Abe Fermentation From Low Cost Substrates, Kai Gao

Electronic Thesis and Dissertation Repository

The high cost of substrate and product inhibition in the fermentation broth remains two major problems associated with bio-butanol production. This thesis aims to solve these problems by examining abundant lignocellulosic biomass as potential feedstocks and exploring novel substrates such as carbohydrates derived from microalgae for ABE fermentation. The commonly observed toxic effect after pretreatment of lignocelluslosic biomass was removed by resin adsorption, where the resin could also serve as an in-situ butanol recvoery devices.

Corn cobs (an agricultural waste), switchgrass (an energy crop) and phragmites (an invasive plant in North America) were investigated as substrates for ABE fermentation by …

Esterification Of Free Fatty Acid By Selected Homogeneous And Solid Acid Catalysts For Biodiesel Production, Mohamed Kaddour

Electronic Thesis and Dissertation Repository

Biodiesel, derived from plant oils and animal fats is an attractive alternative fuel to fossil-based diesel as it is biodegradable, non-toxic, renewable, and has a low emission profile. Industrial production of biodiesel faces major challenges including limited supply of raw material and high cost of feedstock, which accounts for 60-80% of total production cost. Economic feasibility for biodiesel can be improved by using inexpensive raw materials such as waste frying oils and non-edible oils. However, these low quality feedstocks contain significant amounts of free fatty acids (FFA) which reacts with a base to produce soap hindering product separation and reduce …

Biohydrogen And Biomethane Production From Lignocellulosic Biomass, Chinaza Okeoghene Akobi

Electronic Thesis and Dissertation Repository

The main purpose of this study was to investigate the impact of furfural on mixed cultures during fermentative hydrogen production from lignocellulosic biomass. Small batch studies using synthetic lignocellulosic hydrolysate grown on mesophilic mixed cultures, revealed a threshold furfural concentration of greater than 1 g/L with enhancement to the yields (from the control) observed at 0.5 g/L furfural (at initial substrate-to–biomass (S°/X°) ratios of 0.5 and 1 gCOD/gVSS) and at both 0.5 g/L and 1 g/L furfural (at S°/X° of 2 and 4 gCOD/gVSS). This study was scaled-up from 200 mL to 11 L working volume batches, using half the …

Reactor Performances And Hydrodynamics Of Various Gas-Solids Fluidized Beds, Jiangshan Liu

Electronic Thesis and Dissertation Repository

The reactor performances and hydrodynamics were systematically studied in a multifunctional fluidized-bed system which included a bubbling fluidized bed (BFB), a turbulent fluidized bed (TFB) as well as a newly identified circulating turbulent fluidized bed (CTFB) using the same batch of activated FCC particles. Catalytic ozone decomposition was employed as the model reaction to experimentally investigate the reactor performances of BFB, TFB and CTFB. The complete mappings of ozone concentration were obtained in these fluidized beds, showing close relationship with the solids holdup distributions. In the BFBs and TFBs, the study of scale-up effect revealed that the static bed height …

Evaluation Of Voc Degradation In Photo-Catalytic Air Reactors: Tio2 Immobilization, Energy Efficiency And Kinetic Modeling, Cristina S. Lugo Vega

Electronic Thesis and Dissertation Repository

The high VOC emissions from anthropogenic sources are detrimental to both the environment and humans, contributing with ground-level ozone and particle matter formation. Heterogeneous photocatalysis provides significant potential for VOC degradation. However, the approaches to be used for photocatalyst immobilization in scaled and highly efficient photoreactors are still not well established. Furthermore, there is a lack of reported photonic efficiencies and a shortage of required methods to establish these efficiencies.

To address these issues, this PhD Dissertation reports the study of photonic efficiencies, TiO₂ immobilization on a stainless steel mesh and kinetic models in a scaled-up Photo-CREC-Air Reactor. Acetone …

Study On Developments Of Processes For Powder Coatings, Shan Gao

Electronic Thesis and Dissertation Repository

Powder coating, which utilizes polymer resin based powder, is a relatively young technology for decorative and protective purposes. It was first developed in the early 1950s and gradually grew into automotive finishes. Compared to conventional liquid coating, powder coating is an environmentally friendly technology, given that there is no emission of harmful solvent throughout the entire operating process. It is also much more efficient, economical and energy saving as a result of the capability to reuse all the powder. However, there are still some problems in the powder coating process limiting its application. This thesis focused on studying some key …

Formulation And Process Of Powder Coating For Solid Oxide Fuel Cell Interconnects, Yandaizi Zhou

Electronic Thesis and Dissertation Repository

Solid oxide fuel cell (SOFC) interconnects, which are made of chromia-forming ferritic stainless steels, are used to connect individual SOFCs in series to increase the overall cell voltage output. They are usually exposed to high operating temperature (around 800^oC) and both oxidative and reductive atmosphere. Mn_1.5Co_1.5O₄ (MCO) spinel is used for SOFC interconnect coating to decrease the oxidation rate and the chromium migration, and to increase the SOFC lifetime. The current preferred coating method is air-plasma spray (APS) which has transfer efficiency of only around 40%, and is relatively expansive. The objective of …

Ginseng Polysaccharides Nanoparticles - Synthesis, Characterization, And Biological Activity, Kazi Farida Akhter

Electronic Thesis and Dissertation Repository

North American (NA) ginseng is a widely used medicinal plant. Polysaccharides (PS), the major medicinal fractions derived from NA ginseng root, have been shown several biological activities including anti-carcinogenic, anti-aging, immunostimulatory and antioxidant activity. This work focused on nanoprocessing of ginseng PS for enhancing their immunostimulation. Herein, we have developed a novel microfluidic approach to synthesize ginseng PS nanoparticles (NPs) from NA ginseng root. The microfluidics was found to provide unimodal PS spheres down to 20 nm with very narrow particle size distributions. In addition, the immunostimulating effect was investigated on Murine macrophage cell lines, with the results revealing an …

Catalytic Conversion Of Fructose, Glucose And Industrial Grade Sugar Syrups To 5-Hydroxymethylfurfural, A Platform For Fuels And Chemicals, Sadra Souzanchi

Electronic Thesis and Dissertation Repository

5-hydroxymethylfurfural (HMF) as a versatile and polyfunctional compound derived from dehydration of biomass has attracted increasing attentions in research over the past decades. HMF is an important intermediate and platform chemical, which can be converted into different useful chemicals as well as the promising biofuels. It can be obtained from acid-catalyzed dehydration of different C₆-based carbohydrates such as glucose, fructose, sucrose and cellulose.

In this thesis, a cost-effective process for catalytic conversion of simple sugars (particularly glucose and fructose) and industrial grade sugar syrups to HMF was studied in a novel biphasic continuous-flow tubular reactor using inexpensive heterogeneous …

Controlled Delivery Of Angiogenic And Arteriogenic Growth Factors From Biodegradable Poly(Ester Amide) Electrospun Fibers For Therapeutic Angiogenesis, Somiraa S. Said

Electronic Thesis and Dissertation Repository

Therapeutic angiogenesis relies on the delivery of exogenous growth factors to stimulate neovessel formation. However, systemic administration of angiogenic factors results in rapid clearance from the site of interest due to their short biological half-life. In this work, we are reporting controlled delivery of a ‘cocktail’ of growth factors, an angiogenic factor −fibroblast growth factor-2 (FGF2), and an arteriogenic factor −fibroblast growth factor-9 (FGF9), from biodegradable poly(ester amide) (PEA) electrospun fibers towards targeting neovascular formation and maturation. FGF2 and FGF9 were dual loaded into PEA fibers using a mixed blend and emulsion electrospinning technique. Matrigel tube formation and Boyden chamber …

Microwave And Ultrasound Assisted Zeolitization Of Coal Fly Ash, Syed Salman Raza Bukhari

Electronic Thesis and Dissertation Repository

Coal fly ash (CFA) is a major bi-product of coal fired power plants and is a liability for coal power industry. Coal fly ash has been accumulating rapidly around the globe and has been known to be accident prone, resulting in $1.65 billion in clean-up costs and fines. Given the environmental damage CFA is capable of causing, it is a great interest for scientists to recycle this material. Utilization of novel energy such as microwave and ultrasound has been of research interest for the zeolitization of coal fly ash.

This research produced zeolites from CFA utilizing microwave and ultrasound power. …

Direct Conversion Of Wet Microalgae And Oleaginous Yeast To Biodiesel Using Ionic Liquids, Valerie Orr

Electronic Thesis and Dissertation Repository

This thesis examined the development of an oleaginous yeast or microalgae based biorefinery process. First, improvements were made to the Nile Red assay, a high-throughput method for monitoring lipid accumulation in oleaginous organisms resulting in a significantly more reproducible and accurate assay. This assay was then used to optimize lipid production during heterotrophic cultivation of microalgae on glucose using response surface methodology resulting in microalgae with high lipid content (37.6% wt.). In order to improve the renewability of heterotrophic lipid production, both oleaginous yeast and microalgae were cultivated using pyrolytic sugars, produced via fast pyrolysis of pinewood waste. The effects …

Hydrothermal Liquefaction Of High-Water Content Biomass And Waste Materials For The Production Of Biogas And Bio-Crude Oil, Laleh Nazari

Electronic Thesis and Dissertation Repository

Growing interest in renewable energies due to shrinking reserves of fossil fuels and climate change concerns have led to extensive research towards gaseous and liquid fuels production from renewable energy resources such as biomass and wastes. Energy generation from municipal and industrial wastes such as wastewater sludge is also environmental friendly way to deal with large volume of waste disposal with the additional advantage of eliminating part of the indirect greenhouse gas emissions from energy crops-derived biofuels.

In this thesis, a novel process for co-production of biogas and bio-crude oil from high-water-content wastewater sludge through hydrothermal liquefaction (HTL) treatments is …

Particle Agglomeration In A Slurry Bubble Column Due To Interparticle Liquid Bridging, Shona Macintyre

Electronic Thesis and Dissertation Repository

Particle agglomeration in heavy oil upgrading may occur due to the formation of a secondary liquid phase, known as carbonaceous mesophase. This secondary liquid phase is denser and more viscous compared to the continuous phase and may cause operational challenges. The experimental system in this work consisted of biodiesel (continuous liquid), aqueous glycerol (secondary liquid), glass beads, and nitrogen in a cold-flow, non-reacting slurry bubble column. The effects of the secondary liquid loading, secondary liquid viscosity, and particle diameter on the fluid dynamic behaviour are examined. Overall the addition of a denser and more viscous secondary liquid phase was found …

Mechanism Of Ethanol Partial Oxidation Over Titania Supported Vanadia Catalysts: Geometric And Electronic Structure Consequences On Reaction Kinetics, Dongmin Yun

Electronic Thesis and Dissertation Repository

Supported vanadium oxide catalysts (VO_x) are used for a wide range of industrial processes. A significant amount of research has been carried on this specific system with the aim to identify the critical parameters involved in catalytic activity. The results on this relative large body of research indicate that the catalyst support plays a critical role in determining the catalytic activity of vanadia and the use of titanium dioxide as support renders a catalyst with superior activity. Studies on supported vanadia on titanium oxide (VO_x/TiO₂) have provided an understanding on support interactions that result …

Studies On Nanocomposite Coating Produced By Laser-Assisted Process To Prevent Silicone Hydrogels From Bio-Fouling, Vishnuvardhana Wuppaladhodi

Electronic Thesis and Dissertation Repository

In this thesis, silver nanoparticles incorporated into polyvinylpyrrolidone (PVP) were deposited on silicone hydrogel to improve the hydrophilicity of the silicone hydrogel and prevent the growth of bacteria. Two different processes were employed to produce Ag nanoparticles: (1) Process-A is a photochemical reduction; (2) Process-B is laser ablation in liquid. Following that, MAPLE process was employed to deposit the Ag-PVP nanocomposites on the surface of silicone hydrogel. A solid-state pulsed laser (Nd:YAG) with a wavelength of 532 nm at a fluence of 50.4 mJ/cm² was used in the MAPLE system to deposit Ag-PVP nanocomposite coating. Our results indicate that …

Fractionation Of Cornstalk Into Cellulose And Lignin For The Production Of Sodium Carboxymethyl Cellulose, Tao Shui

Electronic Thesis and Dissertation Repository

This thesis project aimed to fractionate cornstalk into cellulose and lignin, and utilize the crude cornstalk-derived cellulose for the production of sodium carboxymethyl cellulose and the lignin for the sybthesis of bio-based phenol-formaldehyde resole resins as wood adhesives. In this thesis work, cornstalk was efficiently fractionated into crude cellulose and crude lignin in mixed solvents of acetic acid, formic acid and water at a solid/agent ratio of 1:5 (g/mL) at 80-100 °C for 120-240 min. The best conditions for organosolv fractionation of cornstalk among the test conditions were determined as follows: mixed solvent of acetic acid/formic acid/water (3:6:1, v/v/v), HCl …

Fermentative Processes Requiring Low Solubility Feed Gases: An Investigation Into Gas-Dependent Microorganisms, Eric W. Doerr

Electronic Thesis and Dissertation Repository

Two bioprocesses were separately investigated based on their common interest of using gaseous substrates that have low solubility. The first process involved the development of a mixed culture using two organisms capable of utilizing glycerol and carbon monoxide separately to increase biobutanol production, while the second process involved an investigation of different production media used in aerobic xanthan production of Xanthomonas campestris with pressurization effects. It was determined that Clostridium pasteurianum should be used with an organism like Clostridium carboxidivorans or Eubacterium limosum in order for butyrate uptake at 3 g/L to occur with a minimum 0.1 g/L butyrate production. …

Passive Acoustic Emissions In A V-Blender, Allison Crouter

Electronic Thesis and Dissertation Repository

The pharmaceutical manufacturing process consists of a number of batch steps; each step must be monitored and controlled to ensure quality standards are met. The development of process analytical technologies (PAT) can improve product monitoring with the aim of increasing efficiency, product quality and consistency and creating a better understanding of the manufacturing process.

This work investigates the feasibility of using passive acoustic emissions (PAE) to monitor particulates in a V-blender. An accelerometer was attached to the lid of a V-blender to measure vibrations from the tumbling solids. A wavelet filter removed the oscillations in the signals from the motion …

Production Of Bio-Based Phenol Formaldehyde Foams, Bing Li

Electronic Thesis and Dissertation Repository

Considering the declining non-renewable fossil resources, there is increasing interest in the development of more environmentally conscious, sustainable and cost-effective substitutes for chemical production. Lignin, a main component in lignocellulosic biomass, has been considered to be a potential substitute for petroleum-based phenol due to its phenolic structure.

This PhD dissertation aimed at producing bio-based phenol formaldehyde (BPF) foams using bio-phenols, including but not limited to, kraft lignin (KL), organosolv lignin (OL), hydrolysis lignin (HL), and bio-crude oil from white birth bark. The challenge of the existing process of producing BPF foams is that a low phenol substitution ratio, generally less …

Treatment Process For Removal Of Naphthenic Acid From Oil Refinery Wastewater, Martin W. Flatley

Electronic Thesis and Dissertation Repository

This thesis covers the sources, chronic fish toxicity and treatment of naphthenic acid in an oil refinery wastwewater system.

Particle Entrainment Studies From Dry And Wet Bed, Saber Ayatollahi

Electronic Thesis and Dissertation Repository

During the Fluid Coking Process™ bitumen is sprayed into a fluidized bed of hot coke particles. The bitumen undergoes thermal cracking and is converted into gasses, condensable vapors, and solid coke, which deposits on the coke particles. These vapors rise through the vessel and result in entrainment of coke particles. Wet fine coke particles from the freeboard region enter the cyclone and contribute to the fouling of the Coker cyclones which can lead to the premature shut-down of Fluid Cokers.

The primary objective of this research is to determine how bed wetness affects entrainment.

First, a new fluidized bed was …