Engineering Commons^™

Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang

Electronic Thesis and Dissertation Repository

The phenol-formaldehyde (PF) resin manufacturing industry is facing a growing challenge with respect to concerns over human health, due to the use of carcinogenic formaldehyde and sustainability due to the use of petroleum-based phenol in PF resin manufacture. Glucose and its derivative, 5-hydroxymethylfurfural (5-HMF), have proven to be potential substitutes for formaldehyde in the synthesis of phenolic novolac resins.

This thesis investigated a number of glucose and 5-HMF resin systems including the curing of phenol-glucose novolac resin (PG) with a bis-phenol-A type epoxy. The curing process was modeled according to the Sestak-Berggren equation (S, B) using Málek methods. This was …

Hydrolytic Depolymerization Of Lignin For The Preparation Of Polyols And Rigid Polyurethane Foams, Nubla Mahmood

Electronic Thesis and Dissertation Repository

This doctoral study was aimed to produce bio-polyols from Kraft lignin (KL) and hydrolysis lignin (HL) via depolymerization and utilize the lignin-derived bio-polyols in the preparation of bio-based rigid polyurethane (BRPU) foams at high percentage of bio-contents (50-70 wt.%). This study demonstrated that depolymerization is a practical and effective approach to unleash the potential of utilization of lignin, of complex structures and low reactivity/functionality, for bioproducts and biomaterials.

Depolymerization of KL was realized in alkaline medium using water alone as a solvent or employing water-ethylene glycol (EG) mixture via a low pressure (psig) proprietary process, both effective for producing low …

Treatment Of Synthetic Oil Sands Tailing Water With Activated Carbon, Alfredo Martinez Iglesias

Electronic Thesis and Dissertation Repository

The extraction of bitumen from the Canadian tar sands has thus far generated approximately 840 billion liters of oil sands process affected water (OSPW) that is currently being stored in containment ponds. OSPW is known to be acutely toxic to various organisms, due to the presence of naphthenic acids (NAs). The scale and sheer volume of OSPW being stored in tailing ponds have generated serious public concerns. Many emerging technologies have been investigated as treatment options for OSPW reclamation. This work studied the feasibility of using granular activated carbon (GAC) to adsorb several naphthenic acids in a model solution of …

Poly(Ester Amide) And Poly(Ethyl Glyoxylate) Nanoparticles For Controlled Drug Release, Amira Mohamed Moustafa

Electronic Thesis and Dissertation Repository

The objective of this research was to develop polymeric nanoparticles (NPs) having improved drug release properties for drug delivery. Poly(ester amide)s (PEAs) are promising biodegradable polymers. PEA NPs were prepared via emulsification-evaporation and salting-out methods and optimized through by varying different processing parameters. Polymer-model drug conjugates based on PEAs containing L-aspartic acid and rhodamine B were synthesized and used for NP preparation. Release behavior was studied and compared to a control system with physically encapsulated rhodamine B. It was shown that the release of rhodamine B from the covalent system did not show the burst effect and exhibited a slower …

Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo

Electronic Thesis and Dissertation Repository

The present study focuses on developing a predictive methodology to scale-up a slurry annular photoreactor using a TiO₂ Degussa P25 from the bench-scale to a pilot-plant scale. The bench-scale photoreactor is a Photo-CREC-Water II, a 2.65 L internally-irradiated slurry annular photocatalytic reactor. The pilot-plant scale photoreactor is a Photo-CREC Water Solar Simulator, a 9.8 L pilot-plant photoreactor, externally irradiated by eight lamps.

The adopted methodology allows the independent validation of radiative and kinetic models avoiding cross-correlation issues. The proposed approach involves two Monte Carlo methods, to model the Radiative Transfer Equation (RTE) inside each photoreactor. With this end, a …

Diffusion And Adsorption Coefficients Of Aromatic Hydrocarbons In Gas Chromatography Capillary Columns, Gabriela Navarro Tovar

Electronic Thesis and Dissertation Repository

This study focuses on a mathematical description of aromatic species elution peaks from a gas chromatographic BPX5 capillary column. Using the chromatographic peaks, statistical moments are calculated for toluene, naphthalene, phenol and 2-naphthol. This thesis reports two modelling approaches involving laminar gas flow, distribution coefficients (K_s) and diffusion coefficients in the stationary phase (D_s).

Firstly, a model with equilibrium adsorption is considered to describe symmetric peaks for toluene and naphthalene. Moreover, a model with non-equilibrium adsorption is proposed to describe asymmetric peaks of phenol and 2-napthol. In addition to the K_s and D …

Impact Of Local Bed Hydrodynamics On Jet-Bed Interaction, Maryam Mohagheghi Dar Ranji

Electronic Thesis and Dissertation Repository

In Fluid Coking^TM or Fluid Catalytic Cracking liquid feedstocks are injected into a bed of fluidized particles. Uniform distribution of liquid feed on fluidized particles increases the yield of valuable products and improves operability in these processes. Contact between the injected liquid and the bed particles can be greatly affected by the liquid properties and local bed hydrodynamics.

The impact of parameters such as liquid properties, fluidization velocity, nozzle atomization gas flowrate, nozzle location and inclination were investigated on the distribution of liquid sprayed into a fluidized bed with a reliable and fast response capacitance meter. This method was …

Effects Of Mixing And Vapor Residence Time On The Thermal Cracking Performance Of Fluidized Beds, Clayton Stanlick

Electronic Thesis and Dissertation Repository

The objective of this thesis is to investigate the effects of applied bed mixing and vapor phase residence time on the thermal cracking of agglomerating and non-agglomerating feedstock. Bitumen thermal cracking was investigated using a novel Mechanically Fluidized Reactor system and a pilot-scale Fluid Coking Reactor. Bed mixing and vapor residence time were studied to determine their impacts on agglomerate distributions, yields, and the quality of liquid product. Birchwood pyrolysis was investigated using a fluidized bed reactor to determine the impacts of particle-bed mixing on the pyrolysis of a non-agglomerating feedstock, to provide contrast to the agglomerating bitumen-coke system. It …

Reductive Depolymerization Of Kraft Lignin For Chemicals And Fuels Using Formic Acid As A In-Situ Hydrogen Source, Shanhua Huang

Electronic Thesis and Dissertation Repository

In this thesis work, formic acid (FA) proved to be an effective in-situ hydrogen donor for the reductive de-polymerization of kraft lignin (KL). At the optimum conditions without catalysts, i.e., 300 ^oC, 1 h, 18.6 wt.% substrate concentration, 50/50 (v/v) water-ethanol medium at a FA-to-lignin mass ratio of 0.7, KL (M_w ~10,000 g/mol) was effectively de-polymerized, producing de-polymerized lignin (DL, M_w 1, 270 g/mol) at a yield of ~90 wt.% and wt.% yield of solid residue (SR). The effects of heterogeneous catalysts on KL reductive de-polymerization in 50/50 (v/v) water-ethanol medium were also investigated. At all conditions, …

Upgrading Of Fast Pyrolysis Oil Via Hdo Using Nano-Structured Catalysts, Shima Ahmadi

Electronic Thesis and Dissertation Repository

The effects of type of solvents (hydro-treated or upgraded pyrolysis oil and ethanol) on hydro-de-oxygenation (HDO) of fast pyrolysis oil were studied. The presence and the type of solvent were found to be effective for prevention or reduction of self-polymerization during the bio-oil HDO process. Using ethanol as the solvent had superior performance in terms of the heating value, molecular weight and elemental composition of the upgraded oil products, compared to using hydro-treated oils as the solvent. Furthermore, novel CoMo catalysts supported on nano-structured materials including MCM-41 and SBA-15 were synthesized and tested on HDO of fast pyrolysis oil in …

Degradation And Biological Assessment Of Aqueous Micropollutant Mixtures, Sura M.H. Ali

Electronic Thesis and Dissertation Repository

Presence of micropollutants in water is a global concern because of their ability to potentially cause adverse effects in organisms at concentrations as low as a few ng/L, particularly when present as a component of complex mixture. Most of the endocrine disrupting compounds (EDC) and pharmaceutical and personal care products (PPCP) are not removed well in traditional wastewater treatment processes and enter the environment and spread throughout the water ecosystem. Depending on the properties of the micropollutants and the biology of the receiving species, they may bioaccumulate, metabolize or cause adverse effects. These effects may translate into alterations on a …

Factors Affecting Bed Agglomeration In Bubbling Fluidized Bed Biomass Boilers, Alejandro Montes

Electronic Thesis and Dissertation Repository

Agglomeration of bed materials at high temperature is one of the most important and challenging problems for fluidized-bed biomass boilers for thermal/power generation. Inorganic alkali components from the fuel can be problematic as they form low-melting alkali compounds. In the present study, the critical amount of liquid (molten ash in real biomass boiler operations) that would result in severe bed agglomeration and defluidization was studied in two small pilot-scales bubbling fluidized bed (BFB) rigs, one operated at room temperature using glycerol-water to simulate molten ash and the other operated at elevated temperatures using low melting-point salt (KOH) to simulate molten …

Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng

Electronic Thesis and Dissertation Repository

Solid phase extraction (SPE) using chemically bonded silica particles or small particles of an organic polymer resin, is being studied extensively for extraction of polar or non-polar compounds from various water matrices. This study focused on the evaluation of the performance of three commercial cartridges belonging to three different groups: reversed-phase, mixed-mode anion exchanger and mixed-mode cation exchanger. In the first stage of research, the performance of three cartridges was compared by extracting four antibiotics with different physic-chemical properties from water samples. The results obtained from column sorption experiments were plotted into breakthrough curves and batch equilibrium experiments results were …

Tissue Engineering Scaffolds With Enhanced Oxygen Delivery Using A Cyclodextrin Inclusion Complex, Tierney Gb Deluzio

Electronic Thesis and Dissertation Repository

The development of a strategy to improve oxygen delivery to cells seeded on scaffolds is essential for the success of tissue engineering applications. The focus of this work was to explore the application of cyclodextrin inclusion complexes (CD:ICs) with perfluorocarbons as oxygen carriers. CD:ICs were prepared from alpha-cyclodextrin and perfluoroperhydrophenanthrene via co-precipitation, paste mixing, and dry mixing complexation techniques. Characterization indicated that paste mixing at a 2:1 host:guest ratio was the most effective method for complexation between the parent molecules. The CD:ICs were then successfully incorporated in 3D fibrous mats via electrospinning with poly(carbonate urethane) and polycaprolactone as biostable and …

Studies Of Anode Electrodes For The Biogenerator, Vahid Vajihinejad

Electronic Thesis and Dissertation Repository

The BioGenerator as a fundamentally new type of H₂-to-electricity conversion system offers a quite sustainable and cost effective solution to the challenges associated with the use of fuel cells in renewable power grids.The development of an anode electrode for the BioGenerator was subject of this work. The unique features of the BioGenerator require unique electrodes, and more specifically anode. The combination of biological cathodic liquid and the hydrogen gas fuel require specific hydrophobic/hydrophilic properties of the anode. Several different methods for anode formation were studied. The spreading technique was found to be most appropriate for the conditions in …

Surfactant Assisted Dispersion Of Single-Walled Carbon Nanotubes In Polyvinylpyrrolidone Solutions, Tennison Yu

Electronic Thesis and Dissertation Repository

Obtaining stable aqueous dispersions is one of the main challenges hindering a widespread and effective use of single-walled carbon nanotubes (SWNT) in many applications. Although it has been recognized that their versatility makes them an extremely attractive material, the unique molecular structure that gives SWNTs their unmatched electronic, mechanical, and thermal properties is also responsible for strong van der Waals interactions. This, combined with extremely high aspect ratios and flexibility, causes SWNTs to adhere strongly into tightly bundled ropes. In these bundles, SWNTs are not as useful as their linearized unbundled equivalents. Thus, in order to take advantage of their …

Laser-Assisted Surface Modification Of Hybrid Hydrogels To Prevent Bacterial Contamination And Protein Fouling, Guobang Huang

Electronic Thesis and Dissertation Repository

Silicone hydrogels have been extensively studied in the fields of contact lenses, tissue engineering, and drug delivery due to their good biocompatibility, high oxygen permeability, and proper light transmission. However, their applications in biomedical devices are limited by protein adsorption and bacterial contamination because of the hydrophobic surface of silicone, which will cause more irreversible protein adsorption. Several physical methods can be applied to create a hydrophilic surface on hydrogels, such as spin coating, physical vapor deposition, dip coating, drop casting, etc. Compared to the conventional methods, the matrix assisted pulsed laser evaporation (MAPLE) is suitable to produce biopolymer/polymer film …

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H₂) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H₂ yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a …

Synthesis, Properties, And Applications Of Carboxylic Acid Functionalized Polyisobutylene, Inderpreet Sran

Electronic Thesis and Dissertation Repository

Polyisobutylene (PIB) and its copolymers are used in a wide range of commercial products owing to their high chemical stability, impermeability, elasticity, and biocompatibility. In this thesis, linear and arborescent PIB containing small percentages of isoprene (IP) were functionalized to provide different derivatives and their physical and biological properties were studied.

Study Of High Pressure Steaming On Lipid Recovery From Microalgae, Ana-Maria Aguirre

Electronic Thesis and Dissertation Repository

Sustainable and clean fuels are in demand due to the perceived negative effects on health and environment with current use of fossil fuels. Lipids from microalgae offer a potential approach to obtain sustainable biofuels. In this study a two step process was adopted: investigation of culture conditions to find optimal points for lipid productivity and cellulose content, followed by an investigation of microalgae disruption for lipid recovery.

In the first phase of the research the effect of culture conditions on Chlorella vulgaris biomass concentration and the ratio of lipid productivity/cellulose content were studied. Response surface methodology was applied to optimize …

Effect Of Nozzle Geometry On Jet Bed Interaction: Experiments With Commercial Scale Nozzles And Eroded Nozzles, Nicholas A. Prociw

Electronic Thesis and Dissertation Repository

Liquid injection into fluidized bed reactors has several industrial applications, such as Fluid Catalytic Cracking, Gas Phase Polyethylene production, and Fluid Coking. High quality liquid distribution is essential to maximize the yield of desirable products, and minimize agglomeration.

The objectives of this thesis are: to develop a method that measures the rate of liquid released from agglomerates formed as a result of liquid injection into a fluidized bed; to use this method to determine the effect of internal erosion on nozzle performance; and to compare the performance of current commercial spray nozzles to nozzles with altered geometries. To achieve these …

Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia

Electronic Thesis and Dissertation Repository

Surface plasmon resonance (SPR) sensing for quantitative analysis of chemical reactions and biological interactions has become one of the most promising applications of plasmonics. This thesis focuses on performance analysis for plasmonic sensors and implementation of plamonic optical sensors with novel nanofabrication techniques.

A universal performance analysis model is established for general two-dimensional plasmonic sensors. This model is based on the fundamental facts of surface plasmon theory. The sensitivity only depends on excitation light wavelength as well as dielectric properties of metal and dielectrics. The expression involves no structure-specified parameters, which validates this formula in broad cases of periodic, quasiperiodic …

Steam Gasification Of Biomass Surrogates: Catalyst Development And Kinetic Modelling, A S M Jahirul Islam Mazumder

Electronic Thesis and Dissertation Repository

This study reports a new fluidizable La₂O₃ promoted Ni/γ-Al₂O₃ catalyst. Prepared catalysts are characterized using BET specific surface area, XRD, TPR, TPO, H₂-pulse chemisorptions, Pyridine FTIR, NH₃-TPD and CO₂-TPD. Catalytic steam gasification of biomass surrogates (glucose and 2-methoxy-4-methylphenol) are conducted in a CREC Riser Simulator under the expected conditions of a twin circulating fludized bed gasifier.

Catalyst structure-property and structure-reactivity relationships are established using characterization and gasification results. Gasification performance of a catalyst is found to be well-correlated as a function of its Ni dispersion and basicity/acidity ratio. …

Humidity Effect On The Structure Of Electrospun Core-Shell Pcl-Peg Fibers For Tissue Regeneration Applications, Adam P. Golin

Electronic Thesis and Dissertation Repository

With the aim of creating a biodegradable scaffold for tympanic membrane (TM) tissue regeneration, core-shell nanofibers composed of a poly(caprolactone) shell and a poly(ethylene glycol) core were created using a coaxial electrospinning technique. In order to create fibers with an optimal core-shell morphology, the effect of relative humidity (RH) on the core-shell nanofibers was systematically studied, with a FITC-BSA complex encapsulated in the core to act as a model protein. The core-shell nanofibers were electrospun at relative humidity values of 20, 25, 30, and 40% RH within a glove box outfitted for humidity control. The core-shell morphology of the fibers …

The Hydrodynamic Behavior Of An Inverse Liquid-Solid Circulating Fluidized Bed, Amin Jaberi

Electronic Thesis and Dissertation Repository

In this work the hydrodynamic behavior of an inverse liquid-solid circulating fluidized bed (ILSCFB) system was studied. In addition, the hydrodynamic characteristic of the inverse liquid-solid fluidization under the conventional fluidization regime was also studied. The system consists of a downer with an inner column diameter of 7.6 cm and a height of 5.4 meters, an upcomer (riser) with an inner column diameter of 20 cm, a separator, and feeding and returning pipes which connect the downer and the upcomer. Based on the axial hydrodynamic behavior of the ILSCFB, it was found that the axial solids holdup in the downer …

Characterization Of Fine Powders And Development Of Processes For Powder Coatings, Jing Fu

Electronic Thesis and Dissertation Repository

Traditional powder coating provides poor coating appearance. Fine powder coating can overcome this drawback since the smaller powder particles lead to much smoother finish. Nevertheless, fine powder has been experienced to cause more application problems. This study investigated fine powder coatings from different aspects and it provided solutions to solve these application problems.

The investigation on fine powders conducted by this study concluded that the medium particle size and D₁₀ was not suitable for the flowability characterization of fine powder coatings. Instead, an index which represented the particle size distribution could correlate with the flowabilities of the fine powder …

Drug Delivery To The Respiratory Tract Using Dry Powder Inhalers, Doaa M.R. Mossaad

Electronic Thesis and Dissertation Repository

Aerosols are an effective method to deliver therapeutic agents to the respiratory tract. Among aerosol generation systems, dry powder inhales have been attractive area of research for both local and systemic delivery of drugs. The challenge of any inhalation delivery system is to generate particles with an adequate range of particle sizes. In order to advance powder aerosol technologies, researchers have recognized the importance of investigating determinants affecting powder dispersion. The effect of particles’ surface characteristics, inhalation airflow rate, inhalation device, and development of an effective drug-carrier system are some of the fundamental areas that have been under investigation.

The …

Quantification Of Axial Solids Mixing And Impacts Of Internals In A Liquid-Solids Circulating Fluidized Bed Downer, Ha Doan

Electronic Thesis and Dissertation Repository

Liquid solids circulating fluidized beds have great potential to be utilized in many chemical processes for their tremendous advantages. There are many studies about the riser but there is not any information on the downer as yet. This research is devoted to study the axial solids mixing in the downer. A new methodology was developed based on the concept of ion-exchanging ability of resins and the residence time distribution measurement. Resin particles were loaded with calcium ion as the tracer and Peclet number and the axial dispersion coefficient were determined for each set of operating conditions. Different designs of baffles …

Antibacterial Studies On Titania Polyurethane Nanocomposite Coatings, Koosha Azhie

Electronic Thesis and Dissertation Repository

While temporary disinfection of a surface is possible with the help of strong cleaners, tremendous interest exists for the control of microorganisms on surfaces by effective, durable antimicrobial coatings. There is a wide spectrum of potential applications for antibacterial coatings, spanning from industrial surface coatings to biomedical applications, where sterile conditions are crucial. This work examined the synthesis of the functionalized 2,2-Dimethylolpropionic acid - nanotitanium dioxide (DMPA-nTiO₂) monomer. Moreover, functionalized nanotitanium dioxide/polyurethane (nTiO₂/PU) composite coatings were prepared using the above mentioned functionalized monomer. The distribution of nTiO₂ in the polymer matrix was enhanced by monomer …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …