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Full-Text Articles in Engineering

Hydrodynamics Of Liquid-Solid And Three-Phase Inverse Circulating Fluidized Beds, Tian Nan Oct 2019

Hydrodynamics Of Liquid-Solid And Three-Phase Inverse Circulating Fluidized Beds, Tian Nan

Electronic Thesis and Dissertation Repository

The hydrodynamics of inverse liquid-solid circulating fluidized bed (ILSCFB) is experimentally studied in a 5.4 m tall and 0.076 m ID column. 5 types of low density particles are investigated with different particle terminal velocities.

Solids holdup distribution is found to be uniform in a wide range of superficial liquid velocities and over 10 solid circulation rates. Average solids hold is not sensitive to particle properties. Clustering phenomenon is found to be significant affecting the slip velocity in the ILSCFB. And the cluster phenomenon is directly related to particle R­eynolds number (Ret). Particles with little Ret ...


Experimental Investigations On The Instantaneous Flow Structure In Circulating Fluidized Beds, Xiaoyang Wei Apr 2019

Experimental Investigations On The Instantaneous Flow Structure In Circulating Fluidized Beds, Xiaoyang Wei

Electronic Thesis and Dissertation Repository

Knowing the instantaneous flow structure is of great importance for the understanding of gas-particle interaction and for the prediction of reactor performances. In this thesis, a systematic and comprehensive study has been conducted on the instantaneous flow structure in a narrow rectangular riser (19 mm in thickness, 114 mm in width and 7.6 m in height), in a cylindrical riser (76 mm in diameter, 10.2 m in height) and in a cylindrical downer (50 mm in diameter, 4.9 m in height). A wider range of operating conditions has been achieved in risers and downer with superficial gas ...


Propane Oxidative Dehydrogenation Under Oxygen-Free Conditions Using Novel Fluidizable Catalysts: Reactivity, Kinetic Modeling And Simulation Study, Samira Rostom Nov 2018

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 VOx/γAl2O3 and VOx/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 ...


Electrocatalysts With High Activity And Stability For Polymer Electrolyte Membrane Fuel Cells, Zhongxin Song Sep 2018

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 Sep 2018

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 ...


Numerical Investigations Of Bubble Column Equipped With Vertical Internals In Different Arrangements, Tuntun Gaurav Aug 2018

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 ...


Production Of Monomeric Aromatics/Phenolics From Hydrolysis Lignin (Hl) By Catalytic Fast Pyrolysis And Hydrothermal Liquefaction, Hooman Paysepar May 2018

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 ...


Hydrogen Generation From Eosin Y-Sensitized Pt/Zno Under Solar Light Irradiation, Tianfang Tian May 2018

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 ...


Co2 Biomass Fluidized Gasification. Thermodynamic And Reactivity Studies., Amanda Kuhn Bastos Mar 2018

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-Al ...


Syngas Chemical Looping Combustion Using A Fluidizable Oxygen Carrier: Reactivity, Kinetics, Reactor Simulation, Imtiaz Ahmed Jan 2018

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 (HPOC) was ...


Photocatalytic Hydrogen Production Using A Mesoporous Tio2 Doped With Pt: Semiconductor Synthesis, Oxidation-Reduction Network And Quantum Efficiencies., Jesus Fabricio Guayaquil-Sosa Jan 2018

Photocatalytic Hydrogen Production Using A Mesoporous Tio2 Doped With Pt: Semiconductor Synthesis, Oxidation-Reduction Network And Quantum Efficiencies., Jesus Fabricio Guayaquil-Sosa

Electronic Thesis and Dissertation Repository

The present PhD dissertation establishes that hydrogen can be produced using mesoporous TiO2 as a photocatalyst, doped with platinum atoms (Pt), in a slurry medium, under near-UV irradiation and with ethanol as a sacrificial reagent (scavenger). These mesoporous TiO2 photocatalysts were prepared using a sol-gel method. The mesoporous Pt-TiO2 photocatalyst displayed a reduced 2.34 eV band gap compared to the bare TiO2 (3.20 eV).

Photocatalytic hydrogen production experiments were performed in a Photo-CREC Water II Reactor (PCW-II Reactor). This novel unit provides both radial and axial symmetrical irradiation profiles. Furthermore, macroscopic energy balances developed ...


Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed Dec 2017

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of ...


Hydrodeoxygenation Of Anisole In A Novel Externally Agitated Reactor, Brett Pomeroy Dec 2017

Hydrodeoxygenation Of Anisole In A Novel Externally Agitated Reactor, Brett Pomeroy

Electronic Thesis and Dissertation Repository

Bio-oil upgrading via hydrodeoxygenation (HDO) was investigated using anisole, a model compound, in a novel Externally Agitated (EA) reactor which is expected to enhance gas-liquid-solid mixing. Operating conditions were established based on anisole HDO with 10 wt.% Ni on silica, γ-alumina, and δ-alumina while varying temperatures between 160 to 280oC, and reaction times between 30 – 90 minutes. Mild temperatures of 220oC and 45 minutes for reaction time with γ-alumina were selected for subsequent work since γ-alumina demonstrated the highest HDO activity. HDO was then investigated with varying Ni-Cu and Ni loadings. Despite the improved reducibility from ...


Hydrothermal Decarboxylation Of Fatty Acids And Their Derivatives For Liquid Transportation Fuels, Md Zakir Hossain Nov 2017

Hydrothermal Decarboxylation Of Fatty Acids And Their Derivatives For Liquid Transportation Fuels, Md Zakir Hossain

Electronic Thesis and Dissertation Repository

Due to the depletion of fossil fuel reserves, renewable resources are required to produce tomorrow’s fuel range hydrocarbons. This thesis focuses on the hydrothermal decarboxylation of fatty acids and their derivatives derived from renewable sources. These are required for liquid transportation fuels which have similar properties to conventional fuels. Detailed catalytic studies were performed for the decarboxylation of oleic acid as a model compound and corn distiller’s oil (CDO) as a real feedstock. Commercial activated carbon and laboratory prepared Ni-Al2O3, MgO-Al2O3, Mo-Al2O3 catalysts were also examined as catalysts. Fatty ...


Hydrodynamics In The Gas-Driven Inverse Liquid-Solid Fluidized Bed, Jiaqi Huang Aug 2017

Hydrodynamics In The Gas-Driven Inverse Liquid-Solid Fluidized Bed, Jiaqi Huang

Electronic Thesis and Dissertation Repository

A novel reactor named Gas-Driven Inverse Liquid-Solid Fluidized Bed (GDFB for short) was developed in this research. A vertical baffle divides the column into a riser and a downer. Inverse fluidization is driven by the gas and occurs in the downer, where hydrodynamics and their influencing factors were studied. In the solid-baffle system, four fluidization regimes were observed, including the packed bed, semi-fluidized bed, fully-fluidized bed, and circulating bed. Bed expansion ratio was higher for particles with a higher density and a smaller solids loading. Moreover, the average particle velocity was proportional to superficial gas velocity and higher for denser ...


Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen Apr 2017

Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen

Electronic Thesis and Dissertation Repository

In order to enhance both the photoactivity and physical/mechanical properties of titania/polyurethane (PU) nanocomposites, in-situ polymerization and film casting were investigated. Both self-degrading PU foams and self-cleaning PU coatings were prepared. Functional monomers were prepared usingDMPA (2,2-dimethylolpropionic acid) functionalized anatse TiO2 and P25 for integration into polyurethane foam with a "grafting-from" synthetic method. This technique was found to successfully reduce the agglomeration effect of titania nanoparticles inside the foams. In addition, the photodegradation rate was enhanced by > 120% over unmodified foam at an optimized loading of 3wt% DMPA functionalized anatase TiO2. The presence of DMPA ...


Multi-Objective Optimization Of Industrial Ammonia Synthesis, Stanislav Ivanov Apr 2017

Multi-Objective Optimization Of Industrial Ammonia Synthesis, Stanislav Ivanov

Electronic Thesis and Dissertation Repository

The thesis describes modelling and optimization work of an industrial ammonia synthesis. Author developed first-principle mathematical model of the commercial converter based on gas-solid reaction and heat transfer within the system. The model is validated with industrial data and showed satisfactory accuracy. Further, optimization study is performed in multi-objective manner to intensify ammonia production and decrease heat duty of the process. Result have revealed a potential to improve current operating condition int terms of both objectives.


Sulfur Species Selective Adsorption Using A New Offretite Based Additive, Yira Yorsirys Aponte Torrealba Nov 2016

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

Electronic Thesis and Dissertation Repository

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

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


Esterification Of Free Fatty Acid By Selected Homogeneous And Solid Acid Catalysts For Biodiesel Production, Mohamed Kaddour Sep 2016

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

Electronic Thesis and Dissertation Repository

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


Reactor Performances And Hydrodynamics Of Various Gas-Solids Fluidized Beds, Jiangshan Liu Aug 2016

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

Electronic Thesis and Dissertation Repository

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


Evaluation Of Voc Degradation In Photo-Catalytic Air Reactors: Tio2 Immobilization, Energy Efficiency And Kinetic Modeling, Cristina S. Lugo Vega Aug 2016

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

Electronic Thesis and Dissertation Repository

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

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


Catalytic Conversion Of Fructose, Glucose And Industrial Grade Sugar Syrups To 5-Hydroxymethylfurfural, A Platform For Fuels And Chemicals, Sadra Souzanchi Aug 2016

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

Electronic Thesis and Dissertation Repository

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

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


Microwave And Ultrasound Assisted Zeolitization Of Coal Fly Ash, Syed Salman Raza Bukhari Aug 2016

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

Electronic Thesis and Dissertation Repository

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

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


Mechanism Of Ethanol Partial Oxidation Over Titania Supported Vanadia Catalysts: Geometric And Electronic Structure Consequences On Reaction Kinetics, Dongmin Yun Aug 2016

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

Electronic Thesis and Dissertation Repository

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


Particle Entrainment Studies From Dry And Wet Bed, Saber Ayatollahi May 2016

Particle Entrainment Studies From Dry And Wet Bed, Saber Ayatollahi

Electronic Thesis and Dissertation Repository

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

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

First, a new fluidized bed was ...


Visible Light Driven Photocatalysis For Degradation Of Diclofenac, Noshin Hashim Apr 2016

Visible Light Driven Photocatalysis For Degradation Of Diclofenac, Noshin Hashim

Electronic Thesis and Dissertation Repository

Diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug (NSAID), is a commonly detected substance that readily accumulates in tissues of aquatic fish and poses a threat to wildlife and freshwater quality. Advanced Oxidation Processes (AOPs) have been explored as an alternative method for complete mineralization of DCF as conventional treatment methods are inadequate for treatment of trace contaminants.

This study employs a semi-batch, swirl-flow, monolithic type photocatalytic reactor to determine intrinsic kinetic parameters of DCF mineralization, in an immobilized system under both UV and visible radiation. The goal of this work to determine true kinetics of DCF, after correcting for ...


Doped Tio2 Nanowires For Applications In Dye Sensitized Solar Cells And Sacrifical Hydrogen Production, Qasem Alsharari Apr 2016

Doped Tio2 Nanowires For Applications In Dye Sensitized Solar Cells And Sacrifical Hydrogen Production, Qasem Alsharari

Electronic Thesis and Dissertation Repository

This thesis explores the synthesis of metal oxide 1-D nanowires using a sol-gel method in supercritical carbon dioxide (sc-CO2), as an environmental friendly enabling solvent. Porous nanowires were synthesized and their performance was tested in dye sensitized solar cell and sacrifical hydrogen production. Titanium isopropoxide (TIP) was used as a precursor for titania synthesis while copper, bismuth and indium were examined as dopants, respectively. The sol-gel reactions were catalyzed by acetic acid in CO2 at a temperature of 60 °C and pressure of 5000 psi. It was observed that acetic acid/monomer ratio > 4 produced nanowires while a ...


Enhanced Solar Photocatalytic Hydrogen Generation And Water Treatment Using Hetero-Structure Photocatalysts, Ghodsieh Malekshoar Feb 2016

Enhanced Solar Photocatalytic Hydrogen Generation And Water Treatment Using Hetero-Structure Photocatalysts, Ghodsieh Malekshoar

Electronic Thesis and Dissertation Repository

Among different approaches to overcome current environmental concerns, heterogeneous photocatalysis is recognized as a promising one. While there are various applications of photocatalysis including water splitting and water treatment, the overall efficiency of this process is still fairly low due to the two dominant drawbacks of current semiconductors, namely wide band gap and fast recombination of photo-generated charges, which restrict the photocatalytic reactions. Designing a hybrid photocatalyst composed of semiconductor hetero-junctions is a viable approach to address these challenges.

The objective of this research project is developing efficient photocatalysts via simple and practical synthesis methods in order to enhance the ...


Catalytic Conversion Of Glycerol To Value-Added Chemical Products, Malaya Ranjan Nanda Sep 2015

Catalytic Conversion Of Glycerol To Value-Added Chemical Products, Malaya Ranjan Nanda

Electronic Thesis and Dissertation Repository

Rapid expansion of biodiesel industry has generated a huge amount of crude glycerol. This thesis aimed to explore utilization of glycerol for the production of solketal as an oxygenated fuel additive and 1, 2-propanediol as a pre-polymer via catalytic conversion.

The thesis work may be divided into two major parts. In the first part, the thermodynamics and kinetics of the glycerol ketalization for the synthesis of solketal were investigated in a batch reactor. From this information, a continuous-flow process was designed, developed and optimized using pure glycerol. Crude glycerol (13 wt% purity) was successfully upgraded into a purified crude glycerol ...


Hydrotreatment Of Lignin Into Green Fuels And Chemicals, Matthew Tymchyshyn Jul 2015

Hydrotreatment Of Lignin Into Green Fuels And Chemicals, Matthew Tymchyshyn

Electronic Thesis and Dissertation Repository

Concerns about declining non-renewable fossil resources, energy security, climate change and sustainability are increasing worldwide. This has resulted in an increased interest in the development of alternatives to fossil resources not only for energy, but particularly for chemical production on a global level. There are a number of promising alternatives to fossil resources, however, lignocellulosic biomass such as forestry residues and wood waste (limbs, bark, sawdust, etc.) seem to be the most promising. They are widely available, renewable and a non-food resource. Therefore woody biomass holds the promise of being a sustainable resources for both energy and chemical production.

The ...