Chemical Engineering Commons^™

Influence Of Coordination Environment On Catalyst Structure And Function For Co2 Hydrogenation And Ethane Partial Oxidation, Juan D. Jimenez

Theses and Dissertations

In this work, we set out to establish strong structure/activity relationships for various catalytic compositions and reactions. Through in situ spectroscopic approaches, specifically DRIFTS, Raman XPS, and XAFS, we were able to discern the reactive species in CO₂ hydrogenation over highly active cobalt nanostructures, the relevant ensemble size and composition of single site catalysts for CO₂ hydrogenation, and active vibrational modes of mixed oxide catalysts for ethane partial oxidation (EPO).

First, we illustrate how tailoring surface orientations of Co₃O₄ catalysts on the nanoscale results in control over catalytic performance via the preferential formation of active …

Multi-Scale Modeling For Transport Study Inside Porous Layers Of Polymer Electrolyte Membrane Fuel Cell Using Direct Numerical Simulation, Pongsarun Satjaritanun

Theses and Dissertations

The direct modeling-based Lattice Boltzmann Agglomeration Method (LBAM) is used to explore the electrochemical kinetics and multi-scalar/multi-physics transport inside the detailed structure of the porous and catalyst layers inside polymer electrolyte membrane fuel cells (PEMFCs). The complete structure of the samples is obtained by both micro- and nano- X-ray computed tomography (CT). LBAM is able to predict the electrochemical kinetics in the nanoscale catalyst layer and investigate the electrochemical variables during cell operation. This work shows success in integrating the lattice elements into an agglomerate structure in the catalyst layer (CL). The predictions using LBAM were compared and validated with …

Production Of Renewable Hydrocarbon Fuel Via Titanium Oxide-Alumina (Tio2-Al2o3) Catalytic Deoxygenation Reaction, Xian Yih Ooi

Student Works (2020-2029)

The renewable hydrocarbon-like biofuel from biomass is crucial to substitute fossil fuel. Catalytic deoxygenation is a biofuel upgrading process to eliminate the high oxygen content in biofuel which will lead to corrosion, instability and lower heating value problems. The choice of support is significant to provide the maximum acid strength for the hydrogenolysis of C-O bonds. Al2O3 supported catalyst has drawn attention due to the high acidity. However, the high acidity leads to coke deposition, unstable and deactivation of the catalyst. Thus, it is important to develop methods to improve catalyst performance, reduce catalyst coking and enhance catalyst lifetime. Recently, …

Poly(Vinyl Alcohol)/Α-Chitin/Nanocellulose Composites Developed From Oil Palm Empty Fruit Bunch (Opefb) For Removal Of Cationic Dyes, Chun Fah Mok

Student Works (2020-2029)

In search of an eco-friendly polymeric adsorbent for dye effluent treatment application, poly(vinyl alcohol) (PVA)/chitin/nanocellulose composites were synthesized. The composites were reinforced by oil palm empty fruit bunch fibers (OPEFB)-derived nanocrystalline cellulose (NCC). With addition of 1 wt.% NCC, a maximum improvement of 57.64% and 50.66% in tensile strength and Young’s Modulus were achieved, respectively. However, the PVA-based composites exhibited low resistance in aqueous medium. Hence, maleic acid (MA) was incorporated, in view of modifying PVA-based composites through cross-linking reactions. The effect of varying chitin content (10 wt.%-30 wt.%) and MA content (10%-50% based on total solid content of composite) …

Tunable Luminescence Of Rare Earth Doped Nanophosphors Via Adaptive Optical Properties Of Transition Metals, Pragathi Darapaneni

LSU Doctoral Dissertations

Over the past decades, the development of light-emitting diodes (LEDs) to produce a wide range of wavelengths has revolutionized the solid-state lighting industry due to their higher energy efficiency and operational lifetimes. These LEDs employ rare earth (RE) doped phosphors due to their stable emission wavelengths which can be amplified when sensitized by other RE dopants (Yb, Ce) or shell layer passivation. However, there has been a push to replace the RE elements in LEDs due to increased socioeconomic issues. One proposed alternative, transition metal (TM) dopants, is typically avoided due to their susceptibility to the local crystal environment resulting …

Research Of Increasing The Reactivity Cotton Cellulose Intended For Chemistry, R.S. Sayfutdinov, U.D. Mukhitdinov, N.M. Eshpulatov

Technical science and innovation

The reactivity of cotton pulp during chemical processing is significantly lower compared to celluloses obtained from other cellulose-containing plants. Increasing the reactivity of cotton cellulose improves the quality of the products based on it, and also increases labor productivity.

The aim of this work is to study the possibility of replacing wood pulp imported from foreign countries with domestic cotton cellulose by increasing the reactivity of cotton cellulose for chemical processing, improving the quality of the resulting product and increasing the reaction rate.

In this work, we used methods for determining the composition and structure of cotton cellulose samples. The …

Electrochemical Characterization Of Bromine Reduction To Tribromide In Individual Nitrobenzene-In-Water Emulsion Droplets, Liang Chang, Allen J. Bard

Faculty Scholarship

We report an electrochemical study of bromine reduction to tribromide in a single nitrobenzene (NB) droplet during a single collision event. The feasibility of this study is based on the favorable distribution of Br2 in NB rather than in water, which was demonstrated by voltammetry at the NB/water interface. The NB-in-water emulsions containing the ionic liquids trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide (ILPA) as the supporting electrolyte and sodium dodecyl sulfate (SDS) as the surfactant were prepared by a high-power ultrasonication. Its single droplet as an attoliter reactor, colliding on a 25 μm Pt UME, was monitored by chronoamperometry. The spike-type current transients of …

Peptide-Modified Chondroitin Sulfate Reduces Coefficient Of Friction At Articular Cartilage Surface, Celina Twitchell, Tanaya Walimbe, Julie C. Liu, Alyssa Panitch

School of Chemical Engineering Faculty Publications

Osteoarthritis is a debilitating disease that results in pain and joint stiffness. Currently, steroidal and nonsteroidal anti-inflammatory drugs and supplements aimed at restoring lubrication to the affected joint are the most successful with respect to improving patient comfort. Due to the success in lubricating therapies, there exists a keen interest to develop better therapies that mimic how lubrication occurs naturally in the joint. Here we describe the results obtained using a chondroitin sulfate chain to which is conjugated peptides that bind to either hyaluronic acid (found in high concentrations in the synovial fluid) or collagen type II (present on the …

Transition Metal-Doped Rare-Earth Oxysulfide Catalysts For High Temperature Dry Reforming Of Methane, Changyi Jiang

LSU Doctoral Dissertations

Carbon dioxide reforming of methane is a catalytic reaction utilizing two kinds of greenhouse gases and converting them into a useful industrial gas stream, “syngas”. However, sulfur poisoning and coke formation are two major challenges for this reaction. In this study, we have synthesized and examined several Ce-La and Ce-Zr oxides, with different transition metal additives. A rapid screening technique was developed to measure reforming and coking rates at low partial pressures. It is a good indicator of catalyst behavior at higher conversions and partial pressures. Following the rapid screening, select catalysts were examined at longer times on stream. Those …

Investigation Of Tracer-Surfactant-Foam Processes In Shallow Subsurface Environmental Remediation: History-Matching And Performance Prediction, Hazem Fleifel

LSU Master's Theses

In-situ subsurface remediation has been widely used as an efficient means of cleaning up non-aqueous phase liquid (NAPL) from contaminated soils and aquifer. The use of tracer, surfactant, and foam are often considered to keep track of the propagation of injected fluids in the medium, dissolve and mobilize contaminants trapped by capillary forces, and overcome the level of heterogeneity and improve displacement and sweep efficiencies.

This study shows an actual remediation process to reduce NAPL within a military base in South Korea, by injecting tracer and surfactant solutions together for a duration of 10 days. The site consists of 5 …

Dissolved Organic Matter-Capped Silver Nanoparticles For Electrochemical Aggregation Sensing Of Atrazine In Aqueous Systems, Ziad Khalifa, Moustafa Zahran Dr, Magdy Zahran Prof, Magdi Abdel Azzem Prof

Chemical Engineering

An electrochemical sensor based on silver nanoparticles (AgNPs) was developed by immobilizing dissolved organic matter (DOM) to interact with AgNPs on a glassy carbon electrode (GC), forming a DOM/AgNP/GC composite. AgNPs have been fabricated and characterized using ultraviolet−visible spectroscopy, fluorescence spectroscopy, and transmission electron microscopy. The immobilization efficiency and stability of the DOM/AgNP/GC composite have been optimized through studying the effects of electrode material type, immobilization technique, sticking duration, supporting electrolyte, and pH using square wave anodic stripping voltammetry. The detection of atrazine (Atz), a common herbicide, in aqueous systems has a great significance because of its toxicity to humans …

Microfluidic Study Of The Electrocoalescence Of Aqueous Droplets In Crude Oil, Thomas Leary, Mohsen Yeganeh, Charles Maldarelli

Publications and Research

In electrocoalescence, an electric field is applied to a dispersion of conducting water droplets in a poorly conducting oil to force the droplets to merge in the direction of the field. Electrocoalescence is used in petroleum refining to separate water from crude oil and in droplet-based microfluidics to combine droplets of water in oil and to break emulsions. Using a microfluidic design to generate a two-dimensional (2D) emulsion, we demonstrate that electrocoalescence in an opaque crude oil can be visualized with optical microscopy and studied on an individual droplet basis in a chamber whose height is small enough to make …

Fabrication Of Perovskite Solar Cells At Uah, Natalie Mann

Research Horizons Day Posters

No abstract provided.

Enhancing Chemical Sensing With Seira And Silicon Carbide Gratings, Autumn Bruncz, Thomas Folland, Joshua Caldwell, Marko Tadjer

Research Horizons Day Posters

No abstract provided.

Dlvo Interactions Of Janus Ellipsoids With A Planar Surface, Kailian Davis

Research Horizons Day Posters

No abstract provided.

Hybrid Monomers & Resins For High-Performance Thermosetting Polymers, Thermoplastics, & Additive Manufacturing, Alexander William Bassett

Theses and Dissertations

Vinyl ester and epoxy resins are used to produce thermosetting polymeric materials for a variety of commercial and military applications due to their relatively high moduli (2-3 GPa at 25 deg C), glass transition temperatures (Tgs) (greater than or equal to 120 deg C), and adequate fracture toughness (G1C approx. 200-250 J m-2). Most commercially available vinyl ester and epoxy resins are typically cured via traditional manufacturing techniques such as resin transfer molding and thermal curing. However, additive manufacturing (AM) has gained significant traction as a favorable manufacturing technique over traditional methods due to the ability to create customizable parts …

Co2 Mass Transfer Enhancement Of Aqueous Amine Solvents By Particle Additives, Leland R. Widger, Guojie Qi, Kun Liu, Jonathan Bryant, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty Patents

The present invention relates to methods for improving carbon capture by providing particles within an amine solvent. The particles provide for increased turbulence at the interface between the counter-flowing gas and solvent, which allows for increased amine and carbamate salt diffusion between the liquid film and bulk.

The Use Of Succinonitrile As An Electrolyte Additive For Composite-Fiber Membranes In Lithium-Ion Batteries, Jahaziel Villarreal, Roberto Orrostieta Chavez, Sujay A. Chopade, Timothy P. Lodge, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications

In the present work, the effect of temperature and additives on the ionic conductivity of mixed organic/ionic liquid electrolytes (MOILEs) was investigated by conducting galvanostatic charge/discharge and ionic conductivity experiments. The mixed electrolyte is based on the ionic liquid (IL) (EMI/TFSI/LiTFSI) and organic solvents EC/DMC (1:1 v/v). The effect of electrolyte type on the electrochemical performance of a LiCoO₂ cathode and a SnO₂/C composite anode in lithium anode (or cathode) half-cells was also investigated. The results demonstrated that the addition of 5 wt.% succinonitrile (SN) resulted in enhanced ionic conductivity of a 60% EMI-TFSI 40% EC/DMC MOILE …

Three-Phase Hydrodynamic Simulation And Experimental Validation Of An Upflow Anaerobic Sludge Blanket Reactor, Camila D' Bastiani, Jéferson Luis Alba, Gabriel Tomazzoni Mazzarotto, Severino Rodrigues De Farias Neto, Anthony Reynolds, David Kennedy, Lademir Luiz Beal

Articles

This research focuses on performing multiphase solid/liquid/gas CFD simulations of a UASB reactor in order to obtain a validated model that provides a clearer understanding of the hydrodynamic behaviour of the three phases in UASB reactors. Eulerian–Eulerian, laminar, three-dimensional, multiphase simulations are carried out using Fluent 16.2. The liquid phase velocity and flow profile are validated through PIV experiments. A liquid mean velocity difference of 8.45% is found between the experimental and numerical results, thus validating the CFD model. Shadowgraphy is applied successfully to validate the biogas phase velocity and bubble size. Based on the hydrodynamic analysis results, the reactor …

Coating Topologically Complex Electrospun Fibers With Nanothin Silk Fibroin Enhances Neurite Outgrowth In Vitro, Alexis M. Ziemba, Tanner D. Fink, Mary Clare Crochiere, Devan L. Puhl, Samichya Sapkota, Ryan J. Gilbert, R. Helen Zha

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electro spun poly-l-lactic acid (PLLA) fibers are commonly used for tissue engineering applications because of their uniform morphology, and their efficacy can be further enhanced via surface modification. In this study, we aimed to increase neurite outgrowth along electro spun fibers by coating with silk fibroin (SF), a bioinert protein derived from Bombyx mori cocoon threads, shown to be neuro compatible. Aligned PLLA fibers were electro spun with smooth, pitted, and devoted surface nano topographies and coated with SF by immersion in coating solution for either 12 or 24 h. Specifically, thin-film coatings of SF were generated by leveraging the …