Catalysis and Reaction Engineering Commons^™

Comparison Of Biomass To Bio-Oils Reactor Systems: Direct Conversion Vs. Companion Coal Gasification, Alexandra Eicher

Honors Theses

It is well known that the United States’ dependence on crude-oil negatively affects its economy, safety, and environment. To alleviate these negative consequences, a more economical and environmentally-friendly source of fuel, such as biomass, should be explored. The conversion of biomass to bio-oils involves the pyrolysis of biomass at about 500°C, thus requiring a great deal of heat. This heat source could be the excess waste heat from a coal gasifier.

As such, this report specifies the design of an industrial plant that produces bio-oils from biomass by using the waste heat from a coal gasifier. It is designed ...

A Novel Mixed Metallic Oxygen Carrier For Chemical Looping Combustion: Preparation, Characterization And Kinetic Modeling, Mohammad Rezwanul Quddus

University of Western Ontario - Electronic Thesis and Dissertation Repository

In last decades, significant concerns have been raised regarding the global warming effect. To date, about one-third of the total anthropogenic CO₂ emission results from power generation using fossil based fuel and CO₂ is the main contributor to global warming. Therefore, technologies for efficient capture of CO₂ are becoming of great value. In this respect, Chemical-Looping Combustion (CLC) has received significant attention as a promising technology facilitating concurrent CO₂ capture and power generation. This non-conventional technique employs a solid carrier, known as oxygen carrier, to supply oxygen and facilitates combustion process in absence of N_{2 ...}

Lignin Yield Maximization Of Lignocellulosic Biomass By Taguchi Robust Product Design Using Organosolv Fractionation, Anton Friedrich Astner

Masters Theses

Lignin, a byproduct of the organosolv pretreatment process using lignocellulosic biomass from switchgrass (Panicum virgatum) and tulip poplar (Liriodendron tulipifera) is currently being explored for its potential use in the production of value-added chemicals and biobased polymers. Pretreatment is one of the most expensive processing steps in cellulosic biomass conversion. Optimization of the process is one of the major goals of the biomass-toethanol conversion process. Taguchi Robust Product Design (TRPD) provides an effective engineering experimental design method for optimizing a system and designing products that are robust to process variations. Given the results of several preliminary studies of the organosolv ...

Catalytic Conversion Of Benzothiophene Over A H-Zsm5 Catalyst, Reactivity And A Kinetic Model, Saad A. Al-Bogami

University of Western Ontario - Electronic Thesis and Dissertation Repository

Nowadays and due to environmental legislations, a world-wide attention has been given towards clean transportation fuels with emphasis on sulfur contents reduction. These efforts on the other hand are challenged by the poor qualities of crude oils. The existing desulfurization technologies such as hydrodesulfurization are not capable to cope with new firm standards. Hence, it is extremely desirable to develop a catalytic desulfurization process to meet both sulfur limits and refining economics. As one aspect of this objective, it is of great importance to study and comprehend the behaviour and chemistry of individual sulfur species present in transportation fuels cuts ...

The Effects Of Ceria Addition On Aging And Sulfation Of Lean Nox Traps For Stand Alone And Lnt-Scr Applications, Vencon G. Easterling

Theses and Dissertations--Chemical and Materials Engineering

THE EFFECTS OF CERIA ADDITION ON AGING AND SULFATION OF LEAN NO_x TRAPS FOR STAND ALONE AND LNT-SCR APPLICATIONS

Model powder and fully formulated monolithic lean NO_x trap (LNT) catalysts were used to investigate the effect of ceria on desulfation behavior. Temperature-programmed reduction (TPR) experiments (model catalysts) showed each of the oxide phases present is able to store sulfur and possesses distinct behavior (temperature at which desulfation occurs). La-CeO₂ or CeO₂-ZrO₂-containing samples (monoliths) showed a greater resistance to deactivation during sulfation and required lower temperatures to restore the NO_x storage efficiency to ...

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 ...

The Synthesis And Characterization Of Novel Group 13 Nanostructured Building Block Heterogeneous Silicate Catalysts, Joshua G. Abbott

Doctoral Dissertations

A building block approach and sequential addition methodology were utilized to prepare heterogeneous silicate catalysts containing atomically dispersed group 13 metal (B, Al, Ga) centers. The octa(trimethyltin) silsequioxane, Si8[sub]O12[sub](OSnMe3[sub])8[sub], was used as the building block for the synthesis of these materials. Reaction of the building block with a variety of group 13 metal chlorides led to the formation of cross-linked matrices. All prepared materials were characterized by gravimetric analysis, gas absorption, IR, and NMR. In addition, aluminum and boron samples where characterized by 27[sup]Al and 11[sup]B solid state ...

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 ...

Characterization Of Heterogeneous Reaction Systems By Thermal Analysis And Mathematical Modeling, Shreya Adhikari, Chuck Tillie

Undergraduate Research Posters 2012

It is anticipated that this research will lead to scale-up parameters that can be used to model a laboratory-scale deposition furnace, and guide further experimentation to advance technologies for protective and conversion coatings.

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 quality ...

Optimization Of Biodiesel Production Plants, Nghi T. Nguyen

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

A conventional biodiesel plant utilizing two distillation columns to purify unreacted reactants and products is considered in this study. Thermodynamic analyses are used to assess the performance of the existing distillation columns, and reduce the costs of operation by appropriate retrofits in a biodiesel production plant. After the retrofits, the overall exergy loss for the two columns has decreased from 2430.87 kW to 1674.12 kW.

A reactive distillation is developed for esterification of lauric acid with methanol using equilibrium and nonequilibrium models. Equilibrium modeling dominated during last few decades due to their straightforward mathematical modeling. In reality, separation ...

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 in a ...

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 ...

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 ...