Engineering Commons^™

Propane Oxidative Dehydrogenation Under Oxygen-Free Conditions Using Novel Fluidizable Catalysts: Reactivity, Kinetic Modeling And Simulation Study, Samira Rostom

Electronic Thesis and Dissertation Repository

Propane oxidative dehydrogenation (PODH) was studied using VO_x/γAl₂O₃ and VO_x/ZrO₂-γAl₂O₃ (1:1 wt.%) catalysts, as well as consecutive propane injections under oxygen-free conditions. These catalysts were synthesized with 2.5, 5 and 7.5 wt.% vanadium loadings, and prepared using a wet saturation impregnation technique. Different characterization techniques were used to establish catalyst properties including NH₃-TPD, pyridine FTIR and NH₃-TPD kinetics. As well, PODH runs in the CREC Riser Simulator were developed under oxygen free atmospheres at 500-550°C, close to 1 atm., 10-20 s and 44.0 catalyst/propane …

Piston Modelling And Gas-Solid Mixing Characterization In Jbr, Tian Dong Cai

Electronic Thesis and Dissertation Repository

The Jiggle Bed Reactor (JBR), a batch fluidized bed microreactor, is inexpensive and easy to operate with a small amount of solids. The main goal of this thesis was to provide practical tools for the design and operation of JBR systems that will ensure good gas-solids mixing.

A model was developed to predict the piston motion. The model uses four empirical parameters that change depending on the equipment characteristics. Two parameters characterize the gas supply to the piston and two parameters are used to describe the frictional forces on the piston. The model was validated with high speed video.

Experiments …

Extraction Of Astaxanthin From H. Pluvialis Using Deep Eutectic Solvents, Roya Barzegar

Electronic Thesis and Dissertation Repository

Haematococcus pluvialis (H. pluvialis) is one of the main sources of astaxanthin, a high value carotenoid and a strong antioxidant. Astaxanthin extraction is hindered by the thick cell wall of H. pluvialis which is composed of sporopollenin. Mechanical cell disruption methods, high cost and energy-consuming, are required to enhance astaxanthin extraction. This study employed a novel technology using deep eutectic solvents (DESs) to demonstrate the possibility of direct extraction of astaxanthin without a disruption step. It was established that 68% of astaxanthin can be extracted from intact H. pluvialis cells using choline chloride-glycerol (ChCl-G) mixture with 12.5% (v/v ) water …

Electrocatalysts With High Activity And Stability For Polymer Electrolyte Membrane Fuel Cells, Zhongxin Song

Electronic Thesis and Dissertation Repository

In addressing the activity and durability challenges facing electrocatalysts in polymer electrolyte membrane fuel cells (PEMFCs), atomic layer deposition (ALD) is emerging as a powerful technique for deposition of noble metals and transition metal oxides due to its exclusive advantages over other methods. The primary advantages of ALD are derived from the sequential, self-saturating, gas-surface reactions, and angstrom level control that take place during the deposition process. Therefore, ALD possesses the advantage in precisely control the particle size and uniform distribution on the substrate. By forming chemical bonds between the initial layer of ALD precursor and support atoms during the …

Hydrogen Production By Photocatalytic Water Splitting Under Near-Uv And Visible Light Using Doped Pt And Pd Tio2, Bianca Rusinque

Electronic Thesis and Dissertation Repository

Photocatalysis is a promising methodology for hydrogen production. It involves the use of an unlimited source of energy, sunlight, and a semiconductor material to split water with zero carbon emissions.

This Master’s thesis reports high efficiencies in terms of hydrogen production via water splitting using 2.0v/v% ethanol as scavenger, platinum and palladium as noble metals on TiO₂ photocatalysts at three metal loadings (1.0, 2.5 and 5.0wt%). Both near UV and visible light were used in the studies developed. These photocatalysts were synthetized using a sol-gel method whose morphological properties were enhanced due to the presence of soft template precursors. …

Chemical Modification Of Lignin Into Advanced Materials, Soheil Hajirahimkhan

Electronic Thesis and Dissertation Repository

Fossil fuel resources are being used today for most of humankind’s energy and chemical/material needs. The inevitable demise of these resources has created significant interest in the field of biomass and particularly, lignin valorization. As the world’s second most abundant polymer, more than 98% of the annually produced lignin is under-utilized either as an on-site heat source, or as landfill. Thus, finding practical approaches to modifying this inexpensive sustainable resource into materials of high value can be the next leap in lessening the dependence on fossil fuel resources and thus, developing a sustainable future.

In this thesis, kraft lignin is …

Modeling Fluid Coker Cyclone Fouling, Erica Glatt

Electronic Thesis and Dissertation Repository

Fluid Coking^TM is a continuous process that thermally converts heavy hydrocarbons, such as oil-sands bitumen, to lighter and higher-value products by horizontal injection onto a fluidized bed of hot coke particles. The deposition of carbonaceous materials in the cyclone sections of commercial Fluid Cokers has been observed throughout each run. The main objective of this work is to improve unit reliability by proposing cyclone fouling mitigation strategies based on a localized phenomenological model using Aspen Plus®. The heavy ends condensation fouling mechanism was studied by incorporating vapour-liquid thermodynamics, thermal cracking reactions, and overall fluid dynamics in the Fluid Coker. …

Biohydrogen Production From Synthetic Lignocellulosic Hydrolysates: Acclimatization And Inhibition, Basem Mikhaeil Fawzy Haroun

Electronic Thesis and Dissertation Repository

The growing concerns regarding climate change, population growth, depletion of fossil fuel, and pollution arising from the combustion of petroleum-based fuel can be identified as the most important factors driving the urgent need for environmentally friendly renewable energy. Among all the recognized alternatives to gasoline-based fuel, hydrogen is not only considered as a clean energy but also it has a high energy content of 142 kJ/g which is almost three times higher compared to other fossil fuels. Only water and heat are the by-products of hydrogen combustion. Dark fermentative hydrogen production is a feasible option in which inexpensive, low-grade, carbohydrate-rich, …

Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan

Electronic Thesis and Dissertation Repository

The use of nitrogen-based fertilizers continues to accelerate with human population growth and increases in global food requirements. Enhanced efficiency fertilizers (EEFs) have been developed to improve the synchronization between nutrient supply and crop nutrient demand. However, many of the current controlled release fertilizers are coated with non-degradable polymers that contribute to accumulation of microplastics within ecosystems. This thesis describes research towards the development of a new class of fertilizer coatings using a self-immolative polymer known as poly (ethyl glyoxylate) (PEtG). PEtG itself does not have suitable properties to produce a viable coating but once blended with another degradable polyester …

Immediate Release Ginseng Chewable Tablets And Sustained Release Amino Acid Pellets Based On Dry Powder Coating Technology Platform, Xiangwei Kong

Electronic Thesis and Dissertation Repository

Based on the dry powder coating technology platform, this study aimed to develop immediate release ginseng chewable tablets using the electrostatic powder coating technique and sustained release amino acid pellets using the plasticizer powder coating technique. For the immediate release ginseng chewable tablets, the content and types of tableting materials, as well as coating materials, coating temperature, curing time and coating level, were optimized. For the sustained release amino acid pellets, coating level and curing time on, as well as the composition of ethyl cellulose (EC), were optimized. In summary, those laboratory studies provided new opportunities for additional potential commercial …

Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Connie Wen

Electronic Thesis and Dissertation Repository

Lignocellulosic material can be subjected to pyrolysis to yield pyrolysis liquid, biochar, and gas. The pyrolysis liquid resulting from the condensation of vapours can be separated into a rich organic condensate and an acidic “aqueous pyrolysis condensate” (APC) which may be considered a waste. The target of this research is subjecting APC to anaerobic digestion to produce biogas that can be energy purposed, and to reduce the organic load of APC to acceptable levels for possible disposal. From this study, it was found that without any treatment, the inoculum requires 50 to 60 days of adaptation period to reduce the …

Hydrodynamics Of A Gas-Driven Gas-Liquid-Solid Spouted Bed, Jia Meng

Electronic Thesis and Dissertation Repository

A novel cylindrical gas-driven gas-liquid-solid spouted bed was developed in this project, which has a high potential to be used for a biological wastewater treatment process. Solids motion, flow regimes, and regime transitions in this system were studied. With increasing gas velocity, four regimes were identified, including: fixed bed, semi spouted bed, full spouted bed and internal circulating fluidized bed. The respective gas velocities for the transitions between the four regimes were experimentally identified and termed as minimum spouting velocity, full spouting velocity and minimum circulating velocity. A new “basketing” method was adopted to measure the minimum spouting velocity while …

Bubble Dynamics And Dense Phase Composition In 2-D Binary Gas-Solid Fluidized Bed, Tianzi Bai

Electronic Thesis and Dissertation Repository

Gas-solid bubbling fluidized bed with binary particles is a potential candidate for performing the dry coal beneficiation process due to its advantages such as the ability to adjust separation density and the elimination of process water. A two-dimensional (2D) fluidized bed was used to study bubble dynamics and dense phase composition distribution in order to gain some fundamental understanding of this system. Digital image analysis (DIA) was employed to measure bubble diameter, bubble rise velocity, bed expansion and particle composition distribution. Magnetite and sand particles as pure and binary mixtures were used in the fluidized bed. Bubble diameter and bubble …

Numerical Investigations Of Bubble Column Equipped With Vertical Internals In Different Arrangements, Tuntun Gaurav

Electronic Thesis and Dissertation Repository

Bubble columns are multiphase contactors with wide applications in industrial processes. Often they are equipped with longitudinal tube bundles to facilitate heat exchange. Studying effects of these internals on column hydrodynamics is vital for the design of these internals. Computational Fluid Dynamic (CFD) simulations provide an understanding of the complex two-phase flow enabling the study of the effects of the internals on the column hydrodynamics. In the present work, an Eulerian-Eulerian based two-fluid model (TFM) coupled with a population balance model (PBM) is used to simulate the gas-liquid two-phase flows in bubble columns. The models studied were validated using experimental …

Impact Of Trace Element Ions And Fe2+ On Anaerobic Food Waste Digestion, Andisheh Yazdanpanah

Electronic Thesis and Dissertation Repository

In Canada, about $31 billion worth of food is wasted annually. This amount of food waste (FW) ends up in landfills where it is naturally broken down by bacteria and releases methane to the atmosphere, a powerful greenhouse gas (GHG) which is 21 times more harmful to the environment than carbon dioxide (CO₂). This process can also be done in a controlled environment at wastewater treatment plants, in a process known as anaerobic digestion (AD). Diverting food waste from landfills to wastewater treatment facilities allows for the capture of the methane, which can be used as an energy …

Autohydrolysis Pretreatment Of Mixed Lignocellulosic Biomass, Claudio Lira

Electronic Thesis and Dissertation Repository

Lignocellulosic biomass, such as agricultural and forestry residues, can be transformed into valuable fuels and chemicals. However, the high cost of feedstock handling and the complex nature of cellulosic biomass processing and conversion remain two major challenges in biorefineries. This thesis aims to tackle these challenges by assessing the transformation of multi-feedstock using autohydrolysis pretreatment.

Corn cobs and stover (residues from corn processing), poplar chips (forestry residue), bagasse and wheat straw (agricultural residues) are abundant and often under-utilized cellulosic residues. These feedstocks were used to investigate the effects of biomass characteristics on the composition of the autohydrolysis pretreatment products. Moreover, …

Corrosion Scale Characteristics And Lead Oxide Dissolution In Chloraminated Water, Daoping Guo

Electronic Thesis and Dissertation Repository

The presence of lead in drinking water is a common issue for utilities where lead pipes are used as service lines in drinking water distribution systems. Dissolved lead concentrations have been linked to the destabilization of stratified lead corrosion scales formed at the inner walls of lead pipe used as drinking water service lines. To develop a framework for lead dissolution control, it is necessary to fully describe the characteristics of the surface layer of the lead corrosion scale in direct contact with drinking water. In the first part of this thesis, a thorough lead corrosion scale characterization is carried …

Process Analytics From Passive Acoustic Emissions Monitoring During Fluidized Bed Pellet Coating In Pharmaceutical Manufacturing, Allan Carter

Electronic Thesis and Dissertation Repository

Piezoelectric microphones were attached to a top spray fluidized bed to provide valuable process signatures. Relationships were developed between sound waves and conditions within the fluidized bed to relay critical quality and performance information. Deep learning analytics were used to extract valuable information from experimental data. Advancements in passive acoustic emissions monitoring will play a key role in optimizing pharmaceutical manufacturing pathways to ensure drug quality and performance.

Production Of Monomeric Aromatics/Phenolics From Hydrolysis Lignin (Hl) By Catalytic Fast Pyrolysis And Hydrothermal Liquefaction, Hooman Paysepar

Electronic Thesis and Dissertation Repository

Bio-oil, produced from bio-feedstocks by thermochemical conversion technologies (e.g., pyrolysis or direct liquefaction), can be renewable replacement for petroleum for energy and chemical production. However, bio oil has high oxygen content, low stability, and low heating value. Thus, upgrading of bio-oil is necessary to remove the oxygen and make it a suitable substitute for conventional liquid transportation fuels or for value-added bio-based chemicals. Oxygen in a bio-oil can be removed by catalytic cracking or hydro-de-oxygenation to the form of H₂O, CO and CO₂ in the presence of a catalyst.

The overall objective of this PhD project was …

Hydrogen Generation From Eosin Y-Sensitized Pt/Zno Under Solar Light Irradiation, Tianfang Tian

Electronic Thesis and Dissertation Repository

Hydrogen is a promising alternative energy carrier. Generating hydrogen via photocatalysts is clean and energy saving comparing to the current technology for hydrogen generation. ZnO has been proved to have photocatalytic activities for wastewater treatment by multiple studies. However, there are not enough studies to investigate its potential to generate hydrogen as the photocatalyst under light irradiation. Therefore, we will investigate the photocatalytic ability of Pt/ZnO to generate hydrogen. Triethanolamine (TEOA) was used as sacrificial reagent while Eosin Y was used as sensitizer. Pt/ZnO was characterized and tested for its activity for hydrogen generation in different conditions, which are platinum …

Maintaining And Controlling An Extrinsic Biofilm For Pathogen Removal In Dental Unit Water Lines, Bilal B. Al-Bataina

Electronic Thesis and Dissertation Repository

The control of biofilm formation is a major concern for industrial, environmental, and public health. Undesirable biofilms can harbor different disease-causing pathogens and shorten the operational life of different equipment. On the other hand, beneficial biofilms are also used in various applications and managing its growth and activity can be desirable. Killing the biofilm does not usually incorporate the removal of the dead biofilm structure that is adhered to the surface. Therefore, the aim of this thesis is to control biofilm formation; to be able to remove, inhibit, and enhance biofilm formation. This thesis investigated the use of norspermidine, D-amino …

Biobutanol Production From Cellulosic And Sugar-Based Feedstock From The Corn Plant, Reyna Gomez-Flores

Electronic Thesis and Dissertation Repository

In this thesis, biobutanol production by biological fermentation was investigated from the corn plant, integrating two approaches. The first one was to utilize corn cobs, a cellulosic-based material. The second, using a new sugar-based material, sugarcorn juice. Utilizing suitable Clostridia strains for each substrate, these approaches converged into a biorefinery concept to produce renewable biofuels in Ontario, Canada. The corn cob pretreatment was carried out by a dilute acid method resulting in temperature as the variable with most significant effect towards glucose liberation. The enzymatic hydrolysis was performed utilizing a very low concentration of an enzymatic stock solution with approximately …

Hydrothermal Liquefaction Of Microalgae For The Production Of Bio-Crude Oil, Yulin Hu

Electronic Thesis and Dissertation Repository

Due to the depletion of fossil fuels and climate change, extensive research has performed towards renewable energy production from microalgal biomass. Microalgae have several inherent benefits, such as high photosynthetic efficiencies, fast growth rates, and high lipid contents. In addition, microalgae can be cultivated in the non-arable lands (e.g., saline and waste water), thereby no competition with food crops production.

Transesterification is the one of commonly used technologies for converting microalgae into liquid bio-fuels (i.e., biodiesel). Normally, an energy-intensive drying step is required in the transesterification treatment, which accounts for nearly half of the energy input. Hence, if “wet” microalgal …

Co2 Biomass Fluidized Gasification. Thermodynamic And Reactivity Studies., Amanda Kuhn Bastos

Electronic Thesis and Dissertation Repository

This study reports biomass gasification in a CREC Riser Simulator under thermal and catalytic conditions. Steam-CO₂ and steam-inert were used as gasifier agents. Biomass feedstocks and a model compound were employed to evaluate gasification performance. It was proven that catalytic steam-CO₂ gasification significantly reduces tar formation while improving carbon conversion to syngas.

Experimental results were compared with thermodynamic equilibrium model predictions. This model accounts for biomass composition, bed temperature and gasifying agents. The model predictions are close to experimental results for steam-CO₂ gasification, leading to a zero CO₂ gain.

2-methoxy-4-methylphenol and 20%Ni-5%CeO₂/γ-Al₂O …

Study On The Surface Features Of Preg-Robbing Carbonaceous Matter During Oxidation Treatment, Mana Pourdasht

Electronic Thesis and Dissertation Repository

Carbonaceous gold ores have the ability to adsorb gold (I) cyanide from leach solutions during processing. This phenomenon, known as preg-robbing, is responsible for poor recoveries as the carbonaceous materials of the ore compete with activated carbon used during the leaching and adsorption phase of processing. Chemical oxidation of carbonaceous materials by different reagents has been utilized to investigate and compare the mechanism of Au (CN)₂ adsorption onto carbonaceous materials prior to and following the treatment.

The procedure for characterization of the carbonaceous materials (plain and modified) in the sample combines the use of several analytical techniques and test …

Covalently Crosslinked Organic/Inorganic Hybrid Biomaterials For Bone Tissue Engineering Applications, Dibakar Mondal

Electronic Thesis and Dissertation Repository

Scaffolds are key components for bone tissue engineering and regeneration. They guide new bone formation by mimicking bone extracellular matrix for cell recruitment and proliferation. Ideally, scaffolds for bone tissue engineering need to be osteoconductive, osteoinductive, porous, degradable and mechanically competent. As a single material can not provide all these requirements, composites of several biomaterials are viable solutions to combine various properties. However, conventional composites fail to fulfil these requirements due to their distinct phases at the microscopic level. Organic/inorganic (O/I) class II hybrid biomaterials, where the organic and inorganic phases are chemically crosslinked on a molecular scale, hence the …

Direct Sheet Molding Compound Process (D-Smc), Atieh Motaghi

Electronic Thesis and Dissertation Repository

The combination of highly crosslinked resin and long glass fiber reinforcement in direct sheet molding compound (D-SMC) provides the parts with high physical properties and low density suitable for large interior and exterior automotive applications. Different stages of D-SMC process including maturation zone and compression molding are studied using mathematical analysis, numerical simulation and experimental investigations.

An analytical analysis is used to calculate the pressure and velocity in the first section of maturation zone and then the permeability of fiber bundle is calculated by simulation and the agreement between the available empirical equation and simulation was obtained. The flow is …

Pyrolysis As An Economical And Ecological Treatment Option For Solid Anaerobic Digestate And Municipal Sewage Sludge, Devon J. Barry

Electronic Thesis and Dissertation Repository

The aim of this thesis was to investigate the potential for pyrolysis of solid anaerobic digestate and municipal sewage sludge. Slow, fast, and autothermal pyrolysis experiments were conducted for the anaerobic digestate while slow and fast pyrolysis experiments were carried out for the sewage sludge. Pyrolysis temperatures ranged from 250 to 550 ᵒC. The effect of pyrolysis conditions on the pyrolysis products was examined.

Fast pyrolysis at higher temperatures was favourable for energy recovery in the bio-oil products. Slow pyrolysis was favourable for the biochar products. Lower pyrolysis temperatures favoured energy recovery in the biochar; while higher temperatures increased biochar …

The Production Of Pyrolytic Biochar For Addition In Value-Added Composite Material, Douglas Matthew Cuthbertson

Electronic Thesis and Dissertation Repository

Pyrolytic biochar has recently gained attention for its potential value as a carbon sequestering by-product that can be used in industrial applications. While biochar is typically targeted for soil amendment applications, higher value applications such as addition in consumer products and building materials needs to be investigated.

In this study, biochar is produced from three different Canadian feedstocks using three different pyrolysis methods. The biochar is characterized to determine the effects that feedstock selection and pyrolysis conditions has on biochar properties. The biochar is also incorporated into concrete at varying concentrations to create a lightweight and sustainable material. The effect …

Syngas Chemical Looping Combustion Using A Fluidizable Oxygen Carrier: Reactivity, Kinetics, Reactor Simulation, Imtiaz Ahmed

Electronic Thesis and Dissertation Repository

Biomass gasification yields a blend of H₂, CO, CH₄ and CO₂, designated as syngas. Syngas can be further combusted using fluidizable oxygen carriers (OCs) during power generation via Chemical Looping Combustion (CLC). To improve syngas CLC and establish its application, a new Ni-based oxygen carrier with a Co and La modified γ-Al₂O₃ support was studied. This type of OC considerably limits the NiAl₂O₄ formation. Therefore, the oxygen carrier was engineered using a special preparation methodology to eliminate NiAl₂O₄ species formation. This promising Highly Performing Oxygen Carrier …