Catalysis and Reaction Engineering Commons^™

Metabolic Engineering For Biocatalyst Robustness To Organic Inhibitors, Liam Royce, Laura R. Jarboe

Chemical and Biological Engineering Publications

Microbial production of biorenewable fuels and chemicals is often limited by inhibition of the biocatalyst, either by increasing concentrations of the product compound or by contaminant compounds in the biomass‐derived sugars. This inhibition can interfere with economically viable production. Here we discuss typical mechanisms of inhibition and methods for improving biocatalyst robustness. Inhibition often takes the form of inhibition of enzyme activity, depletion of cofactor pools, and membrane damage; methods are discussed for mitigating each of these types of inhibition. Various evolutionary schemes have been developed and implemented on a variety of inhibitory compounds, including butanol, acetic acid, furfural ...

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

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 ...

Effect Of Density Ratio On Velocity Fluctuations In Dispersed Multiphase Flow From Simulations Of Finite-Size Particles, Vahid Tavanashad, Alberto Passalacqua, Rodney O. Fox, Shankar Subramaniam

Chemical and Biological Engineering Publications

Velocity fluctuations in the carrier phase and dispersed phase of a dispersed multiphase flow are studied using particle-resolved direct numerical simulation. The simulations correspond to a statistically homogeneous problem with an imposed mean pressure gradient and are presented for Rem=20 and a wide range of dispersed phase volume fractions (0.1≤ϕ≤0.4) and density ratios of the dispersed phase to the carrier phase (0.001≤ρp/ρf≤1000) . The velocity fluctuations in the fluid and dispersed phase at the statistically stationary state are quantified by the turbulent kinetic energy (TKE) and granular temperature, respectively. It is found ...

Selective Glucose Isomerization To Fructose Via Nitrogen-Doped Solid Base Catalyst Derived From Spent Coffee Grounds, Season S. Chen, Iris K.M. Yu, Dong-Wan Cho, Hocheol Song, Daniel C.W. Tsang, Jean-Philippe Tessonnier, Yong Sik Ok, Chi Sun Poon

Chemical and Biological Engineering Publications

In this work, glucose isomerization to fructose was conducted via a solid base biochar catalyst derived from spent coffee grounds and melamine. The X-ray photoelectron spectroscopy (XPS) spectra identified the majority of pyridinic nitrogen on the biochar surface, which imparted the strong base character of the catalyst. Activity of the catalyst was evidenced by fast conversion of glucose (12%) and high selectivity to fructose (84%) in 20 min at a moderate temperature (120 °C) compared to recently reported immobilized tertiary amines at comparable N concentrations (10-15 mol% relative to glucose). By increasing the reaction temperature to 160 °C, fructose yield ...

Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman

Chemistry Faculty Publications

Heterogeneous photocatalysis is a prominent area of research with major applications in solar energy conversion, air pollution mitigation, and removal of contaminants from water. A large number of scientific papers related to the photocatalysis field and its environmental applications are published in different journals specializing in materials and nanomaterials. However, many problems exist in the conception of papers by authors unfamiliar with standard characterization methods of photocatalysts as well as with the procedures needed to determine photocatalytic activities based on the determination of “apparent quantum efficiencies” within a wavelength interval or “apparent quantum yields” in the case of using monochromatic ...

Thin-Film Block Copolymers (Bcps) Self-Assembly As Versatile Patterning Scheme For Functional Nanomaterials, Le Zhang

LSU Master's Theses

Nanopattern generation is required for building various structural entities in every production process that involves nanostructures. Advancing nanopatterning technologies play an important role in developing and broadening the current nanopatterning technologies to meet up with the ever-demanding requirements in the realm of smaller feature sizes, smoother line-edge roughness (LER) and facile pattern transfer in pursuit of faster computer processors, better electrocatalysts and more compact and intelligent sensors, etc. Conventionally, patterning needs are heavily relied on photolithography, a technique that dominate chip-making industry for more than 50 years. However conventional photolithography is bounded by inherent resolution limits and difficult to be ...

Nanoflower-Like Bi2moo6/Ag3po4 In Water Treatment, Xavier Morgan-Lange, Jaeyun Moon, Kaleab Ayalew

McNair Poster Presentations

No abstract provided.

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 ...

Mechanistic Studies Of Reducible Metal Oxides As Hydrodeoxygenation Catalysts, Akbar Mahdavi Shakib

Electronic Theses and Dissertations

Hydrodeoxygenation of phenol to benzene using ruthenium supported titania catalysts strongly varies depending on the support crystal structure and preparation conditions. Here, we performed spectroscopic characterization of titania supports to identify the surface impurities common to commercial and synthesized titania samples using a variety of spectroscopic methods. Sulfate impurities were detected for the commercial anatase samples and a procedure for their elimination was proposed so that inactive catalysts gained reactivity. Surface hydroxyls of different TiO2 samples (anatase, rutile, and pyrogenic) were identified using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments performed on vigorously cleaned surfaces and a facet-specific assignment ...

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 ...

Platinum-Gallium (Pt-Ga) Intermetallic Alloys For Propane Dehydrogenation, Brittany K. Roopnarine, Nicole J. Libretto, Johnny Zhuchen, Zhenwei Wu, Evan Wegener, Griffin Canning, Abhaya K. Datye, Jeffrey T. Miller

The Summer Undergraduate Research Fellowship (SURF) Symposium

Natural gas is a source of energy for the United States. The Center for Innovative Strategic Transformation of Alkane Resources (CISTAR) plans to use shale gas extracted from shale rock formations as a bridge fuel to replace coal and oil while the US transitions to renewable energy like solar and wind. After methane, the largest components in shale gas are light alkanes such as ethane and propane. These can be catalytically converted to olefins, which can be further reacted to produce fuels, for example. Olefins from alkanes can be accomplished by dehydrogenation by promoted platinum alloys. This study compares the ...

Computational Catalysis: Creating A User-Friendly Tool For Research And Education, Kevin P. Greenman, Peilin Liao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Catalysis is used in a significant portion of production processes in the industrialized world, including most processing of chemicals and fuels. This makes maximizing the efficiency of catalysts a high priority. However, the immense number of candidates for new catalysts precludes the possibility of testing all of them by experiments. Density functional theory (DFT) has been widely and successfully used to calculate material properties relevant to catalysis and to screen promising candidates for experimental testing, but there currently exists no publicly- available, user-friendly tool for performing these DFT calculations. This work details the development of such a tool for nanoHUB ...

Scaling Relationships Across Chemically Related Adsorbates For Fast Screening Of Alloy Catalysts For Propane Dehydrogenation, Anne Esther Serban, Ranga Rohit Seemakurthi, Brandon C. Bukowski, Jeffrey Greeley

The Summer Undergraduate Research Fellowship (SURF) Symposium

A catalyst is a material which speeds up the rate of a specific reaction. A reaction that is of significant importance to the chemical industry is the selective transformations of light alkanes (ethane, propane), which are largely available in shale gas, to olefins. These olefins can then be converted into higher-value chemicals, materials, and fuels. However, there are several undesired reactions that take place alongside the main dehydrogenation reaction, so a catalyst of high selectivity is desired. Apart from the industrially used PtSn catalyst, work by our experimental collaborators has shown that various other Pt and Pd alloys (In, Zn ...

Identification Of Proximal And Isolated Aluminum Heteroatoms In Zeolites By Infrared Spectroscopy, Melanie A. Brunet Torres, Philip Kester, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

High demand for energy production and limited fossil fuel reserves are two factors that motivate intense research for new alternative energy resources. While we are still far from completely moving to renewable energy solutions, a new solution that replaces crude oil and coal with shale gas is currently under investigation. For this modern technology, new zeolite catalysts need to be developed for the conversion of light hydrocarbons gases to liquid transportation fuels. These catalysts are of special interest in the production of liquid fuels since they exhibit high reaction rates, molecular sieving properties and selectivity behavior. In this work, the ...

Investigation Of The Effects Of Solid-State Treatments On The Structure And Mobility Of Copper In Zeolites, Jiayang Wu, Laura Wilcox, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

Zeolites are microporous, aluminosilicate catalysts that play an important role in industrial applications as well as studies for the fundamental understanding of catalysts for emerging reactions of interest. The introduction of aluminum into the zeolite lattice introduces a negative charge on the framework that can be balanced with extra-framework cations. The control of the aluminum distribution and the choice of charge balancing cations allows for the ability to tailor the active sites to facilitate a desired reaction. This research focuses on studying copper active sites in zeolites. Copper oxide was used as a copper precursor to introduce copper ions in ...

Thermal Fluid Model Development Of Steam Methane Reformer Using Artificial Neural Network, M. A. Rafe Biswas

M. A. Rafe Biswas

Increased Energy Yield Through Fast Pyrolysis: Empowering Malawian Villages, Diehl Mutamba

Undergraduate Honors Theses

Biomass contributes to several renewable energy technologies. This project will explore the use of fast pyrolysis to produce fuels by designing an apparatus for fast pyrolysis. Malawian people harvest firewood from the forests, which is a major contributor to deforestation. Furthermore, they convert some of it to charcoal with about 10-15% efficiency to sell to city dwellers. The project will enable herbaceous fuels to replace wood, increase charcoal yields and create new products. Firewood and charcoal produce smoke and carbon monoxide (CO) that compromises the villagers’ health.

This project will address deforestation problems, improve sustainability, decrease health hazards and improve ...

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

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 ...