Engineering Commons^™

Disinfection By-Products Formation After Coagulation Of Algal Extracellular And Intracellular Organic Matters, Tianyiru Chen

Electronic Thesis and Dissertation Repository

Algal organic matter (AOM) is found in high concentration during algal bloom season in drinking water systems, which is generally categorized into extracellular organic matter (EOM) and intracellular organic matter (IOM). These compounds are not well removed in traditional water treatment methods such as coagulation, and are the precursors of subsequent disinfection by-products (DBPs) during chlorination of water. In this study, EOM and IOM content of four different algae were quantified measuring dissolved organic carbon (DOC), UV absorbance at 254 nm and turbidity. Coagulation using alum (Al₂(SO₄)₃•16H₂O)was used to remove the algal …

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 …

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 …

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 …

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 …

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 …

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 …

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. …

Minor Whey Protein Purification Using Ion-Exchange Column Chromatography, Naeimeh Faraji Dizaji

Electronic Thesis and Dissertation Repository

This thesis is concerned with application of mechanistic models for recovery and purification of two minor milk proteins to develop an efficient and robust process. A fundamental and quantitative understanding of the underlying mechanisms assists to evaluate chances and challenges in non-linear chromatography.

The first chapter considers adsorption isotherm data of two minor whey proteins on cation exchanger under various conditions and used as the basis to develop a predictive approach for correlating adsorption behavior using a mechanistic isotherm model. The SMA isotherm model explicitly considers the contributions of protein-adsorbent and protein-protein interactions in the simulation of salt gradients in …

Recovery Of Valuable Chemicals From Agricultural Waste Through Pyrolysis, Mohammad M. Hossain

Electronic Thesis and Dissertation Repository

Agricultural crop residues are a source of inexpensive biomass to convert into bioproducts. The recovery of valuable chemicals from plant waste would partly solve the disposal issue and offer a more environmentally friendly alternative to synthetic chemical production. One approach to separate and concentrate valuable chemicals from biomass is pyrolysis using a batch reactor process. A mechanically fluidized reactor (MFR) was developed to pyrolyze biomass from ambient to temperatures near 600 °C, forming gases that are then condensed in an ice-chilled condenser to form a bio-oil. The bio-oil produced by the MFR can be separated within temperature ranges, termed one-dimensional …

A Study Of Low C/N Ratio Waste Water Treatment Using Fluidized Bed Bioreactor, Kai Li

Electronic Thesis and Dissertation Repository

In wastewater treatment field, one of the severe challenges is the handling of ammonia-rich wastewater with a low C/N ratio. The failure of nitrogen treatment can lead to adverse ecological and biological effects including depletion of dissolved oxygen, eutrophication, toxicity to aquatic life, and reduction in the suitability of water for reuse. Conventionally, extra organic carbon dosing is required in treating low C/N wastewater. Alternately, partial nitrification is of interest as an emerging technology for its’ lesser need of organic carbon addition and cost savings in aeration. In this study, a lab-scale partial nitrification fluidized bed bioreactor (PNFBR) and a …

Polymeric Superparamagnetic Nanoparticles For Drug Delivery Applications, Leena Mohammed

Electronic Thesis and Dissertation Repository

Drug delivery systems based on magnetic nanoparticles present a promising avenue for controlled targeted therapeutics, especially in cancer therapy. Conventional systematic therapeutics encompasses numerous side effects due to its limited selectivity between healthy and cancerous cells. In this thesis, novel polymeric-metallic hybrid nanoaggregates were developed to address this challenge. Magnetite nanoparticles were synthesized via precipitation of iron oxide and was surface modified using a unique chitosan derivative, glycol chitosan (GC), loaded with progesterone for potential hormonal therapy application for breast cancer. Surface characterizations techniques, in vitro drug release kinetics, investigation of progesterone release mechanism by mathematical modeling, and cell cytotoxicity …

Polyhydroxybutyrate Production In A Photobioreactor Using Spirulina Platensis, Adrianna Mika

Electronic Thesis and Dissertation Repository

Biopolymers and other naturally derived chemicals continue to gain attention over petrochemical based products due to the price volatility of crude oil, increasing need to reduce greenhouse gas emissions and public awareness of environmental issues. Cyanobacterium Spirulina (Arthrospira) platensis, a commercially feasible blue-green alga, is able to synthesize poly(3-hydroxybutyrate) (PHB), a biodegradable and biocompatible polymer, as an energy storage product of photosynthesis directly from CO₂. A flat plate photobioreactor (PBR) with LED illumination was designed for the cultivation of S. platensis. Computational fluid dynamics (CFD) software was used to improve airflow uniformity and mixing in the …

Pyrolysis Based Biorefineries For The Production Of Fermentable Substrates, Luis Carlos Luque-Moreno

Electronic Thesis and Dissertation Repository

Fast pyrolysis is rapid thermal conversion process capable of transforming multiple feedstocks into various energy carriers, specifically pyrolysis oil, bio gas, and bio char. The oil phase is of high value due to its complex mixtures of organic molecules, along with large number of anhydrous carbohydrates, which can be easily transformed into glucose via acid hydrolysis. These carbohydrates can be either biocatalyzed into fuels and chemicals by microorganisms or converted after further treatment steps. However quantities of these carbohydrates in the oil are a function of feedstock composition and process parameters. The research presented in this thesis focuses on producing …

Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian

Electronic Thesis and Dissertation Repository

Microbial fuel cells (MFCs) are widely researched for application in wastewater treatment. However, the current anodes used in MFCs often suffer from high fabrication cost and uncontrollable pore sizes. In this thesis, three-dimensional printing technique was utilized to fabricate anodes with different micro pore sizes for MFCs. Copper coating and carbonization were applied to the printed polymer anodes to increase the conductivity and specific surface area. Voltages of MFCs with various anodes were measured as well as other electrochemical tests such as linear sweep voltammetry and electrochemical impedance spectroscopy. 3D copper porous anode produced higher maximum voltages and power densities …

Biohydrogen Production From Cellulose By Clostridium Termitidis And Clostridium Beijerinckii., Maritza Gomez-Flores

Electronic Thesis and Dissertation Repository

The purpose of this study was to determine Clostridium termitidis microbial kinetics on glucose, cellobiose, and cellulose, and to assess its co-culture with Clostridium beijerinckii for hydrogen production. Microbial kinetics parameters of the mesophilic, cellulolytic, and hydrogen producer C. termitidis were determined on glucose and cellobiose using MATLAB for modelling biomass growth and substrate consumption. Hydrogen yields on these substrates were 1.99 and 1.11 mol H₂ mol^-1 hexose equivalent, respectively. C. termitidis microbial kinetics in mono-culture and in co-culture with mesophilic hydrogen producer C. beijerinckii were also investigated under agitated and non-agitated conditions, with hydrogen yields of 1.46 …

Evaluation Of Filtration Performance Of A Rotating Belt Filter For Different Primary Wastewater Influents., Tulip Chakraborty

Electronic Thesis and Dissertation Repository

Human activities around the world are responsible for production of enormous amount of wastewater, which needs to be treated quickly and effectively to avoid environmental concerns and other health implications. As an alternative to primary settlers in treating municipal wastewater, Salsnes, a subsidiary company of Trojan Technologies offers rotating belt filters (RBF) to treat the wastewater. A bench scale filtration unit of the RBF was developed to investigate the effect of varying water qualities from several wastewater plants in London, Ontario on the performance of the filter. The unit can achieve up to 80% reduction in total suspended solids (TSS), …

Process Control For Biological Nutrient Removal Processes In Fluidized Beds Treating Low Carbon To Nitrogen Municipal Wastewater, Joseph Donohue

Electronic Thesis and Dissertation Repository

Conventional wastewater treatment techniques - utilizing microorganisms to remove organics and nutrients (i.e. nitrogen and phosphorus) from a water stream and partially incorporate them into their cell structure - struggle to adapt with increased urbanization due to land and infrastructure requirements. The circulating fluidized-bed bioreactor (CFBBR) was developed as a way to provide biological treatment in an urbanized area by cultivating high-density bacteria on an inert media. The technology operates as a pre-anoxic nitrification/denitrification wastewater treatment process. The system is initially loaded with media, providing a platform for microbial growth. Internal recycle streams in the system provide the energy to …

Synthesis, Characterization And Applications Of Lignin-Based Epoxy Resins, Fatemeh Ferdosian

Electronic Thesis and Dissertation Repository

Epoxy resin is one of the most versatile thermosetting polymers with diverse applications. Epoxy resins are mainly produced from the reaction of bisphenol-A (BPA) and epichlorohydrin. The consumption of bisphenol-A is facing growing concerns over its carcinogenic effects and its sustainability. Lignin can be a promising renewable substitute of bisphenol-A in the synthesis of epoxy resins.

In this thesis work, a novel method has been developed for the synthesis of bio-based epoxy resins with reduced side reactions, employing de-polymerized lignin from organosolv lignin (DOL), kraft lignin (DKL) and hydrolysis lignin (DHL) under alkaline condition in the presence of a phase …

Towards Intensified Protein Refolding And Purification On Size Exlusion Chromatography: Fundamental Studies And Mathematical Modelling, Pegah Saremirad

Electronic Thesis and Dissertation Repository

For industrial recombinant-protein processes, protein refolding and purification are crucial steps towards the recovery of considerable numbers of active and safe therapeutic products. In this thesis, intensification strategies for protein refolding and purification processes are explored. Development of an intensified process aims at simultaneous optimization of process performance indicators, namely: refolding yield, product purity, volumetric productivity and solvent consumption which in turn decrease the cost and time constraints to market.

The first strategy investigated related to multivariable experimental work using size exclusion chromatography (SEC) as a refolding method and a denatured/reduced model protein (lysozyme). SEC was selected due to its …

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 …

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, …

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 …

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 …

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 …

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 …

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 …