Engineering Commons^™

Effect Of Liquid-Solid Contact On Thermal Cracking Of Heavy Hydrocarbons In A Mechanically Fluidized Reactor, Mitesh C. Chaudhari

Electronic Thesis and Dissertation Repository

The aim of the thesis was to study the effect of liquid-solid contact on the thermal cracking of heavy hydrocarbons carried out in Fluid Cokers. The research has been carried out using a Mechanically Fluidized Reactor (MFR) in which the operating conditions of the Fluid Coking^TM reactions can be simulated and monitored. The first part of the research, aimed at investigating the effect of agitation on liquid-solid contact, which was carried out by changing the rotation speed of the agitator of the MFR for both non-reactive as well as for reactive systems. In both situations, it was observed that …

Photocalytic Degradation Of Malic Acid Under Thin Coated Tio2, Vanessa Silveira Rodgher

Electronic Thesis and Dissertation Repository

Opaque fluids have a limited irradiation transmission. Thus, their decontamination employing near UV irradiation poses significant technical challenges. In the present study, a thin UV-transparent/waterproof glue layer coated with a 1.5 wt% of TiO₂ and a new PhotoReactor Cell were implemented. TiO₂ irradiation in the PhotoReactor Cell was effected on the TiO₂ particle side, not directly in contact with the fluid, allowing the postulation of an “h⁺” site mobility mechanism on photocatalysis.

Photocatalytic degradation experiments with malic and malonic acid in water at 10, 20, 30 and 40 ppm showed the complete degradation of malic …

Production Of Bio-Coal And Activated Carbon From Biomass, Diana C. Cruz

Electronic Thesis and Dissertation Repository

The slow pyrolysis of different biomasses (maple wood, birch bark, switch grass, coffee pulp and corn stalk) was studied with the aim to produce a solid pyrolysis product (bio-coal) with promising properties and potential for use in traditional fossil-coal applications. Batch pyrolysis experiments were conducted in a Mechanically Fluidized Reactor (MFR) at temperatures ranging from 143 to 665 ^oC, which includes the torrefaction temperature range (200-300 ^oC). The effects of temperature and holding time on bio-coal mass yields were determined. The bio-coals were characterized in detail and a highly-controlled study on bio-coal hygroscopicity is presented. Optimal conditions for …

Fractional Condensation Of Bio-Oil Vapors, Akhil Tumbalam Gooty

Electronic Thesis and Dissertation Repository

The research project described in this thesis deals with an investigation on the fractional condensation of bio-oil vapors to improve the separation of some of the key components of the bio-oil and, consequently, improve the properties and the value of each of the separated product streams.

In the first part, the separation of a mixture of three model compounds of bio-oil from a vapor and carrier gas stream was investigated with the help of a series of three condensers maintained at different temperatures. The practical performance of the fractional condensation train was improved by comparing the experimental results with the …

Optimization Of Chiral Separation Of Nadolol By Simulated Moving Bed Technology, Nesma Nehad Hashem

Electronic Thesis and Dissertation Repository

Simulated Moving Bed (SMB) technology has gained increasing attention as one of the most powerful techniques for chromatographic separations due to its cost-effectiveness and efficiency. Application of SMB technology is especially important in the pharmaceutical industry for production of enantiopure drugs, as required under strict FDA regulations, to avoid possible adverse effects of racemic drugs. In this study, the performance of the SMB process in separation of racemic nadolol on a perphenyl carbamoylated beta cyclodextrin (β-CD) stationary phase was investigated. The equilibrium dispersive model coupled with bi-Langmuir adsorption isotherm and lumped kinetic approximation, constitute the mathematical model used to simulate …

Controlled Synthesis Of Single-Walled Carbon Nanotubes By Methane Decomposition And Their Application As Heterogeneous Partial Oxidation Catalyst, Inusa Abdullahi

Electronic Thesis and Dissertation Repository

Single-walled carbon nanotubes (SWCNTs) are materials with unique electronic and mechanical properties suitable for a large number of applications. Although, since their discovery many strategies for SWCNT synthesis have been explored, most of these are either tremendously energy intensive or require complex SWNCT purification strategies. These issues have resulted in expensive SWCNT production processes which in turn have hampered the development of a large range of SWCNT applications. This study deals with the controlled growth of SWCNTs from methane decomposition over iron and cobalt catalysts supported on MgO and the application of the CCVD grown SWCNTs as a catalyst for …

Light And Heat Selective Polymer Nanocomposite Films For Sustainable Greenhouses, Jenna M. Allan

Electronic Thesis and Dissertation Repository

Ontario greenhouse operations offer the ability to provide safe, local produce year-round. However, energy consumption associated with this service, as well as limited light intensity during winter months, is a significant problem. For this reason quantum dot (QD) nanoparticles and silica aerogel (SA) granules were investigated as potential filler materials for the enhancement of the optical and thermal properties of poly (ethylene-vinyl acetate) (EVA), a common greenhouse plastic, for the concurrent goals of increasing biomass production and reducing energy consumption in greenhouses.

The QDs, synthesized by colloidal chemistry using a single-molecular precursor method, along with commercial SA particles were integrated …

Study On The Interactions Between Nanomaterials And Proteins, Yueqi Bi

Electronic Thesis and Dissertation Repository

Incorporating proteins with nanomaterials is an effective way to enhance the stability and function of proteins. The protein-nanomaterials hybrid systems have been extensively applied in drug delivery and biocatalysis. This thesis focuses on the different interactions between proteins and nanomaterials. Three sub-projects have been studied as follows;

1) Chemical interaction: Gold nanoparticles with a particle size of 15nm were applied to label bovine serum albumin (BSA), a globular protein, for realizing a colorimetric protein assay. The results of FTIR and Raman spectra indicate that gold nanoparticles bond to BSA via the amine bonds. The surface plasma resonance (SPR) of …

Preparation And Formulation Of Powder Coating For Application Of Enamelled Wire, Liuyin Xia

Electronic Thesis and Dissertation Repository

Enamelled wire is a conductive wire coated with a very thin layer of insulation, widely used in the field that requires tight coils of wire. The traditional enamelled wire is produced by liquid paint, which consists of resins, solvents, pigments, and additives. Organic solvent takes a relatively high content, normally of 75% to 90% by weight. Many efforts have been made to decrease the percentage of solvent in the insulation paint. On the other hand, increasing the solids content of given enamel results in the viscosity rises significantly, making it harder to flow. Therefore, powder coating technology as an alternative …

Calcium Phosphate-Based Resorbable Biomaterials For Bone Regeneration, Daniel O. Costa

Electronic Thesis and Dissertation Repository

Bone defects are a prevalent problem in orthopedics and dentistry. Calcium phosphate-based coatings and nanocomposites offer unique solutions towards producing scaffolds with suitable physical, mechanical and biological properties for bone regeneration.

We developed a novel method to synthesize hydroxyapatite (HA) particles with high aspect ratio using sol-gel chemistry and hydrothermal treatment. We obtained tunable pure-phase carbonated-HA in the form of micro/nanorods and nanowires (diameters 25-800 nm). To mimic the structure of bone, HA nanowires were homogenously mixed within poly(ε-caprolactone) (PCL) to produce nanocomposites with improved mechanical properties as determined by uniaxial tensile testing.

Surface chemistry and topography of biomaterials play …

Nano Tio2/Graphene Composites For Photovoltaic And Photocatalytic Materials, Nasrin Farhangi

Electronic Thesis and Dissertation Repository

Graphene has been recognized as one of the most exciting carbon based materials of the present decade due to its unique electronic, mechanical and thermal properties. High surface area exfoliated graphene sheets with controllable surface functionality is an attractive two-dimensional surface for attaching different metals and semiconductors for improving the performance of catalysts, sensors, photoelectronic and energy conversion devices. Graphene is an ideal material which can be used for improving various metal oxide properties such as those of titania (TiO₂). TiO₂/graphene composites have shown excellent properties compared to bare TiO₂ in various applications. In high …

Simultaneous Particle Agglomeration And Attrition In A High Temperature Fluidized Bed, Mithun Saha

Electronic Thesis and Dissertation Repository

Fluid Coking^TM is a major refining process to upgrade heavy crude oil or bitumen from oil sands. In Fluid Coking^TM bitumen is atomized with steam and sprayed inside a high temperature fluidized bed of coke particles where it thermally cracks into smaller molecules. Fluid Coking^TM is a carbon rejection process as solid carbon residues are formed during fragmentation into lighter hydrocarbon vapors. New coke deposits over existing coke particles and, consequently, the particle size increases. In addition, particles agglomeration occurs when the injected liquid does not disperse uniformly on individual hot coke particles but reaches, instead, local …

Water Treatment Using Advanced Oxidation Processes: Application Perspectives, Charles R. Gilmour

Electronic Thesis and Dissertation Repository

Advanced oxidation processes (AOPs) using hydroxyl radicals and other oxidative radical species are being studied extensively for removal of organic compounds from various waste streams. However, large scale applications of these highly effective technologies in water and wastewater treatment are still very limited due to cost and inadequate information about the resultant water quality. This study focuses on the evaluation of the upstream processing and downstream post treatment analysis of selective AOPs. In the first stage of research, the performance of a proprietary catalyst (VN-TiO₂) was compared with the industry standard P25 TiO₂, for the use …

Improved Non-Linear Solution Of Dip Coating Flow, Omar Bin Yusuf

Electronic Thesis and Dissertation Repository

A thin layer of film is developed on the surface of a substrate in the dip coating process where the substrate is initially immersed into the coating fluid and then withdrawn continuously from the coating fluid bath. In this study a two dimensional flow of the thin film for a Newtonian fluid is examined theoretically by dividing the film into three separate regions. A general formulation is developed for a thin film flow, which then simplifies for each region upon considering appropriate assumptions to each region. The influence of inertia and surface tension in the presence of gravity is investigated …

Disinfection Of Low Uv Transmittance Fluids: Fundamentals And Applications, Housyn Mahmoud

Electronic Thesis and Dissertation Repository

Modern consumer demands for tasty, safe and healthier liquid foods and beverages. Chemical preservatives are usually added to foods to extend their shelf life and to protect against food borne pathogens. Application of ultraviolet (UV) light is gaining more attention as an alternative technology to disinfect fluids with low UV transmittance replacing classical chemical or thermal procedures due to growing negative public reaction over chemicals added. UV light irradiation has a positive consumer image as it is a physical non-thermal method efficient against microbial hazards, chemicals free cost effective and energy efficient methods and has been approved by regulatory agencies. …

Numerical Simulation Of Catalytic Ozone Decomposition Reaction In A Gas-Solids Circulating Fluidized Bed Riser, Lei Kong

Electronic Thesis and Dissertation Repository

Computational fluid dynamics (CFD) modeling of catalytic ozone decomposition reaction in a circulating fluidized bed (CFB) riser using iron impregnated FCC particles as catalyst is carried out. The catalytic reaction is defined as a one-step reaction with an empirical coefficient. Eularian-Eularian method with kinetic theory of granular flow is used to solve the gas-solids two-phase flow in the CFB riser. The simulation results are compared with experimental data, with the reaction rate modified using an empirical coefficient to provide better simulation results than the original reaction rate. Moreover, the particle size has great effects on the reaction rate. Studies on …

Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim

Electronic Thesis and Dissertation Repository

One of the most important parameters to cultivate microalgae is carbon dioxide absorption by microalgae. Therefore, it is necessary to determine the overall volumetric mass transfer coefficient (K_La) of carbon dioxide to quantify CO₂ transfer from the gaseous to the liquid phase. Until now, finding K_La of CO₂ for microalgae cultivation has been a challenge as there is not much information available about it in the literature and most of the time the CO₂ transfer to microalgae is approximated. In this study, correlations to directly calculate K_La of CO₂ in …

Solar And Visible Light Driven Photocatalysis For Sacrificial Hydrogen Generation And Water Detoxification With Chemically Modified Ti02, Pankaj Chowdhury

Electronic Thesis and Dissertation Repository

Photocatalysis is a recognized approach where light energy is employed to excite the semiconductor material producing electron/hole pair which eventually involves in the detoxification of pollutants and/or water splitting producing hydrogen. Existing photocatalysts suffer from poor activity or no activity in visible light irradiation which restricts them from solar light utilization. This work is focused on two key applications of photocatalysis (i) sacrificial hydrogen generation, and (ii) phenol degradation in visible and/or solar light. Platinum was loaded on TiO₂ photocatalyst by solar photo-deposition method. Eosin Y dye was used as a sensitizer for sensitization of platinum loaded TiO_{2 …}

Chiral Separation Of Racemic Mandelic Acid By The Coupling Crystallization Process And Simulated Moving Bed Technology, Shimin Mao

Electronic Thesis and Dissertation Repository

Chirality is a major concern in the modern pharmaceutical, food and agricultural industries. The importance of enantiopure drugs has risen dramatically in recent years due to FDA regulations requiring that all chiral bioactive molecules must be isolated and tested for the efficacy and safety, and have to be as pure as possible containing a single pure enantiomer. There are essentially three strategies that can be applied to obtain single pure isomers: (a) extraction from plants and animal materials (b) enantio-selective asymmetric synthesis so that only one isomer is formed in the first place, or (c) making a racemate and finding …

Synthesis And Characterization Of Graphene-Polymer Nanocomposites Via Reversible Addition-Fragmentation Chain-Transfer Polymerization, Renpeng Gu

Electronic Thesis and Dissertation Repository

Graphene has emerged as a subject of tremendous scientific interest due to its exceptional electrical, mechanical and thermal properties. When incorporated into a polymer matrix, graphene sheets can significantly improve the properties of the host polymer. However, the dispersion of pure graphene throughout a polymer matrix is not homogeneous, due to the strong van der Waals interactions between graphene sheets and the difference in surface compatabilities. To prevent agglomeration of these graphene sheets, surface functionalization is required. The goal of this thesis was to develop a facile approach for growing polymer chains from the surface of graphene sheets via reversible …

Liquid Distribution From Industrial Scale Spray Jets In Fluidized Beds, Mohammadali Zirgachianzadeh

Electronic Thesis and Dissertation Repository

Liquid injections via spray nozzles are used in fluidized bed reactors such as Fluid Cokers. In such industrial processes, in order to maximize the product yields it is required to optimize the performance of the nozzle. Moreover parts of the bed might become defluidized, bogged, due to high liquid load. Then optimizing the performance of the nozzle and local bed bogging detection is the primary research objectives for this thesis work.

The first part of the research work was focused on developing a novel method employing electrical conductance to characterize the liquid distribution in a large scale fluid bed of …

Photocatalytic Reactors For Air Treatment: Energy Efficiencies And Kinetic Modeling, Juan M. Garcia Hernandez

Electronic Thesis and Dissertation Repository

The energy efficiency of the photocatalytic conversion of gas-phase organic pollutants was studied using a redesigned and scaled up Photo-CREC-Air reactor. This photocatalytic unit has the unique feature of allowing an accurate analysis of the irradiation field by establishing macroscopic balances and in-situ measurements. The Photo-CREC-Air reactor operates in a batch mode with the photocatalyst supported by a stainless steel mesh being irradiated by 8 UV lamps. Kinetic modelling, Quantum Yields (QY) and Photochemical Thermodynamic Efficiency Factors (PTEF) were calculated using data for acetone , acetaldehyde and isopropanol photocatalytic degradation in ambient air utilizing a Degussa P25 …

Gasification Of Bio-Oils To Syngas In Fluidized Bed Reactors, Mohammad Latifi

Electronic Thesis and Dissertation Repository

Bio-fuels are renewable and clean which can be used as alternatives to fossil fuels or can be used in combination with them. Biomass is a main source of bio-fuels production: it is a renewable resource and its conversion to energy releases no net CO₂ to the environment.

Bio-oil, the valuable liquid product obtained from biomass through pyrolysis, may be either combusted to generate carbon-neutral electricity or converted to a synthesis gas from which chemicals or clean fuels can be produced. Producing bio-oil from biomass and then converting the bio-oil to syngas has several advantages: The bio-oil may be generated …

Bubble-Free Oxygen And Carbon Dioxide Mass Transfer In Bioreactors Using Microporous Membranes, Ravi Balgobin

Electronic Thesis and Dissertation Repository

Increasing gas-liquid mass transfer in bioreactors is a major goal for performance improvement in bioprocesses. The effects of bubble-free oxygen and carbon dioxide mass transfer using microporous membranes were tested in a flat module and a hollow fiber module for applications in a bio-fuel cell and cultivation of microalgae. The volumetric mass transfer coefficient, K_La, was compared to conventional bubbling. Liquid agitation rates influenced the mass transfer, as the limiting factor was the liquid boundary layer thickness. The K_La increased as the membrane hydrophobicity increased. The effect of pore size was found to be negligible …

Developing Novel Methods To Characterize Liquid Dispersion In A Fluidized Bed, Masoumeh Farkhondehkavaki

Electronic Thesis and Dissertation Repository

The performance of several important industrial processes, such as fluid coking or fluid catalytic cracking, is dependent on the good distribution of liquid feed sprayed into a fluidized bed of hot inert or catalytic particles, respectively.

Liquid injected into a fluidized bed is distributed in three different ways: (i) free moisture, or liquid coating individual particles; (ii) wet micro-agglomerates, which are fluidized; and (iii) wet macro-agglomerates, which settle to the bottom of the bed. This study develops and evaluates various methods for the determination of this moisture.

In the study using electrical techniques, two different kinds of electrodes geometries are …

Oxygen Delivery Strategies In Tissue-Engineering Constructs, Dawit Gezahegn Seifu

Electronic Thesis and Dissertation Repository

The supply of nutrients and the removal of waste products play a major role in tissue engineering. From all the nutrients necessary for cells seeded on scaffolds for tissue regeneration, oxygen is the limiting component due to its low solubility in culture media while cells consume five to six moles of oxygen for every mole of monosaccharide. The aim of the present work was to develop different strategies to improve the supply of oxygen to human coronary artery smooth muscle cells (HCASMC) seeded on three dimensional (3D) porous biostable polyurethane scaffolds. As a springboard for the study, the measured value …