Engineering Commons^™

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

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 …

Application Of Mechanically Fluidized Reactors To Lignin Pyrolysis, Valentina Lago

Electronic Thesis and Dissertation Repository

Lignin has great potential for the production of aromatics currently derived from petroleum, since it is the most abundant source of aromatics in nature. At present, Kraft lignin is used as fuel within the pulping process but, alternatively, it could be converted to high-value chemicals using thermochemical processes such as pyrolysis. Kraft lignin, however, is a very cohesive and thermally sensitive powder with foaming and agglomerating tendency under reaction conditions. Therefore, new reactor designs are necessary to efficiently process this raw material.

Consequently, a novel reactor design, designated as Mechanically Fluidized Reactor (MFR) has been developed to successfully process Kraft …

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 …

Disinfection And Advanced Oxidation Of Highly Absorbing Fluids By Uv/Vuv Light: Process Modeling And Validation, Ferdinando Crapulli

Electronic Thesis and Dissertation Repository

One of the limitations in treating highly absorbing fluids with ultraviolet photoreactors is the short light penetration into the fluid leading to the following issues: (a) if not engineered properly, ultraviolet photoreactors dealing with highly absorbing fluids are likely to be energy-inefficient due to a non-ideal use of emitted photons and non-uniform dose distribution (b) the quantification of photo-chemical rate constants could be a challenging task due to the severe mixing-limited conditions of the experimental apparatus used during the investigation. As a result, new lab-scale apparatus (alternative to the conventional collimated beam system) and modeling approaches are needed in order …

Solar Photocatalytic Reduction Of Zn2+ Using Graphene-Based Tio2 Composite Catalyst For Application To Cso Treatment, Gloria Kumordzi

Electronic Thesis and Dissertation Repository

The improvement of photocatalyst efficiency in utilizing the majority of wavelengths in the solar spectrum, an abundant natural resource, presents the next step in the large scale application of photocatalysis for the treatment of dissolved organic and inorganic pollutants in wastewater. In this study, a composite catalyst of TiO₂ and Graphene synthesized by a hydrothermal treatment method is used to photo-reduce Zn²⁺, the most abundant heavy metal found in combined sewer overflows (CSOs). The performance of this composite catalyst was assessed under various process conditions such as pH, light intensity, catalyst loading and light source. The TiO …

Cluster Fluid Dynamics In Down Flow Reactors: Experimental And Modeling Study, Angel Virgilio Lanza Soto

Electronic Thesis and Dissertation Repository

Gas–solid concurrent downers possess unique features when compared to other gas–solid systems. Establishing their fluid dynamic properties requires both experimental measurements of gas-solid flow properties and computational modeling.

Measuring gas-solid flow properties such as cluster solid concentrations, individual cluster slip velocities, and cluster sizes, involves the use of specialized optical equipment, as well as a rigorous data analysis methodology. In addition, the modeling of the fluid dynamics of gas-solid flows in downer units offers special challenges such as establishing a proper drag model, cluster configuration and sizes, sphericity, boundary conditions, among other issues.

In this PhD dissertation, the fluid dynamics …