Chemical Engineering Commons^™

Effect Of Surface Oxidation On The Mechanics Of Carbon Nanotube Laden Interfaces, William Daniel Ivancic

ETD Archive

Single and multi-walled carbon nanotubes (SWCNT & MWCNT) have been studied over the past three decades because of their excellent properties, including their mechanical strength and large electrical and thermal conductivities. Incorporating CNTs into phases necessary for use in consumer or industrial products has been challenging because of strong attractive interactions, heterogeneity, and lack of separation techniques for these nanomaterials. Moreover, there are further challenges incorporating CNTs into multiphase materials because of the many remaining open questions regarding the properties of an interface with CNTs adsorbed or nearby. In the present work, the mechanics and microstructure of a water/air interface …

Experimental Analysis Of Catalytic Gasification Of Waste Polymers, Samuel O. Sanya, Uc Obiako, Aliandra Barbutti, Stephen Reeves, Eric M. Lange, Jade Moten

Undergraduate Research Posters 2017

This research focuses on advancing the current knowledge of a catalytic gasification process as a potential in-situ resource utilization and waste management system. This research has significance in a variety of engineering applications, but is of particular relevance towards municipal waste management and advancing space exploration. In this technology, typically referred to as Trash to Supply Gas (TtSG), liquid phase oxidation reactions produce carbon monoxide, carbon dioxide, and water. The oxidation reactions are complemented by two gas-phase reactions: the Water Gas Shift (WGS) and the Sabatier (or methanation) reaction, the main stages in the pathway of producing hydrogen and methane …

P2: Image Analysis And Quantification Of 3d Cancer Cell Migration, Stephen Hong, Alexander Roth

Undergraduate Research Posters 2017

Metastatic tumors are known for their ability to migrate toward circulatory apparatus and detach from the primary tumor. Generally, metastasis is quantified in vitro using migration assays that are normally measured in two dimensions (2D). Threedimensional (3D) migration assays can better mimic cancers by providing similar microenvironments to those observed in vivo. Imaging 3D cell cultures requires multiple 2D images stacked along a Z-axis; however, imaged cells would be in-focus at varied z-positions at different time points due to the characteristics of cell migration. Our goal in this study was to analyze in-focus cell images and quantify cell migration in …

P1: Dispersion And Characterization Of Boron Nitride Nanotubes Stabilized By Dna, Camerin Mcdonald

Undergraduate Research Posters 2017

Boron nitride nanotubes (BNNTs) are newly emerging nanomaterials with extraordinary mechanical properties as well as thermal and chemical stability. There have been growing interests in both fundamental studies and technological development of BNNTs such as protective coatings for high temperature and hazardous environments due to recent success in large scale synthesis of BNNTs. In this work, various DNA sequences were utilized to stabilize aqueous dispersions of BNNTs. First, we determined the optimum mass ratio of 1:1 for BNNTs:DNA using (GT)20 by UV-vis absorbance measurements. Second, the DNA length effect on the dispersion yield of BNNTs was investigated using sequences (GT)3, …

Fully Compositional Multi-Scale Reservoir Simulation Of Various Co2 Sequestration Mechanisms, Denis V. Voskov, Heath Henley, Angelo Lucia

Chemical, Biomolecular, and Materials Engineering Faculty Publications

A multi-scale reservoir simulation framework for large-scale, multiphase flow with mineral precipitation in CO₂-brine systems is proposed. The novel aspects of this reservoir modeling and simulation framework are centered around the seminal coupling of rigorous reactive transport with full compositional modeling and consist of (1) thermal, multi-phase flow tightly coupled to complex phase behavior, (2) the use of the Gibbs-Helmholtz Constrained (GHC) equation of state, (3) the presence of multiple homogeneous/heterogeneous chemical reactions, (4) the inclusion of mineral precipitation/dissolution, and (5) the presence of homogeneous/heterogeneous formations. The proposed modeling and simulation framework is implemented using the ADGPRS/GFLASH system. …

Dna–Carbon Nanotube Complexation Affinity And Photoluminescence Modulation Are Independent, Prakrit V. Jena, Mohammad M. Safaee, Daniel A. Heller, Daniel E. Roxbury

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Short single-stranded DNA (ssDNA) has emerged as the natural polymer of choice for noncovalently functionalizing photoluminescent single-walled carbon nanotubes. In addition, specific empirically identified DNA sequences can be used to separate single species (chiralities) of nanotubes, with an exceptionally high purity. Currently, only limited general principles exist for designing DNA–nanotube hybrids amenable to separation processes, due in part to an incomplete understanding of the fundamental interactions between a DNA sequence and a specific nanotube structure, whereas even less is known in the design of nanotube-based sensors with determined optical properties. We therefore developed a combined experimental and analysis platform on …

Progress Toward Applications Of Carbon Nanotube Photoluminescence, Prakrit V. Jena, Thomas V. Galassi, Daniel E. Roxbury, Daniel A. Heller

Chemical, Biomolecular, and Materials Engineering Faculty Publications

In the fifteen years following the discovery of single-walled carbon nanotube (SWCNT) photoluminescence, investigators have made significant progress in their understanding of the phenomenon and toward the development of applications. The intrinsic potential of semiconducting carbon nanotubes – a family of bright, photostable near infrared (NIR) fluorophores (900–2100 nm) with tunable properties, has motivated their use as optical probes and sensors. In this perspective, we highlight the advances made in the synthesis, processing, modification, separation, and metrology of carbon nanotubes in the context of applications of their photoluminescence.

Single Nanotube Spectral Imaging To Determine Molar Concentrations Of Isolated Carbon Nanotube Species, Thomas V. Galassi, Prakrit V. Jena, Daniel E. Roxbury, Daniel A. Heller

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Electronic and biological applications of carbon nanotubes can be highly dependent on the species (chirality) of nanotube, purity, and concentration. Existing bulk methods, such as absorbance spectroscopy, can quantify sp² carbon based on spectral bands, but nanotube length distribution, defects, and carbonaceous impurities can complicate quantification of individual particles. We present a general method to relate the optical density of a photoluminescent nanotube sample to the number of individual nanotubes. By acquiring 3-dimensional images of nanotubes embedded in a gel matrix with a reducing environment, we quantified all emissive nanotubes in a volume. Via spectral imaging, we assessed structural …

Hybrid Metal Oxide Cycle Water Splitting, Richard B. Diver Jr., Robert D. Palumbo, Nathan P. Siegel, James E. Miller

Other Faculty Research and Publications

Hybrid thermochemical water splitting systems are disclosed that thermally reduces metal oxides particles to displace some but not all of the electrical requirements in a water splitting electrolytic cell. In these hybrid systems, the thermal reduction temperature is significantly reduced compared to two-step metal-oxide thermochemical cycles in which only thermal energy is required to produce hydrogen from water. Also, unlike conventional higher temperature systems where the reduction step must be carried out under reduced oxygen pressure, the reduction step in the proposed hybrid systems can be carried out in air, allowing for thermal input by a solar power tower with …

Synthesis, Characterization, And Activity Of Co/Fe Alumina/Silica Supported Ft Catalysts And The Study Of Promoter Effect Of Ruthenium, Sunday Azubike Esumike

Doctoral Dissertations

The alumina and hybrid alumina-silica FT catalyst were prepared by one-step solgel/oil-drop methods using metal-nitrate-solutions (method-I), and nanoparticle-metaloxides (method-2). The nanoparticle-metal-oxides did not participate in solubility equilibria in contrast to metal nitrate in method-1 causing no metal ion seepage; therefore, method-2 yields higher XRF metal loading efficiency than method-1. The thermal analysis confirmed that the metal loading by method-1 and method-2 involved two different pathways. Method-1 involves solubility equilibria in the conversion of metal-nitrate to metal- hydroxide and finally to metal-oxide, while in method-2 nanoparticle-metal-oxide remained intact during sol-gel-oil-drop and calcination steps.

The alumina supported catalysts were dominated by γ-alumina …

Microemulsion Formation Of Vegetable Oils Using Mixed Extended Surfactant For Cleaning Applications, Siriluk Jariyawattanarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Some vegetable oils and animal fats can form semi-solid crystalline. The formation of semi-solid fats or waxy soils results in weak interactions between the oil and surfactant during the cleaning process. In this study, the anionic extended surfac-tant (C14-15, 8PO-SO4) systems were employed to form a middle phase microemul-sion with various vegetable oils (coconut, palm and soybean oil). The addition of nonionic extended surfactant (C16-18, 2PO-4EO-OH) in the mixed surfactant systems was also evaluated to observe the solubility enhancement of oil and water phase. The IFT value of formulated surfactant systems was measured to determine the optimum salinity. The Hydrophilic-Lipophilic …

Synthesis Of Magnetic Carbon Nanoparticles Using Pyrolysis Of Glycerol And Ferrocene For Antibiotic Removal, Konrat Kerdnawee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Synthesis of magnetic carbon nanoparticles (M-CNPs) via nebulizing co-pyrolysis of glycerol and ferrocene with magnetic induction was successfully conducted. Experimental investigation on influence of synthesizing temperature and ratio of glycerol to ferrocene suggested that at 800 °C of synthesizing temperature with an initial weight ratio of glycerol to ferrocene of 3:1, the highest M-CNP synthesizing yield of 15.9 % was achieved. With the presence of magnetic induction, controlled synthesis of M-CNPs could be anticipated as a promising method for producing M-CNPs with high quality and high yield. Oxy-tetracycline (OTC) has been recognized as environmental contamination due to its over-dosage and …

Development Of Conductive Polyimide/Polysulfone Composites As Positive Temperature Coefficient Materials, Noppawat Kuengputpong

Chulalongkorn University Theses and Dissertations (Chula ETD)

For positive temperature coefficient (PTC) applications of electrically conductive composites, volume resistivity at room temperature of lower than 104 Ω.cm is one major requirement. Conductive polyimide (PI) PTC with the above level of conductivity value can be achieved by a use of carbon black (CB) as conductive filler. For materials with PTC, there is a change in resistance related to temperature. In order to reduce the amount of CB used in the PTC composites, one of well-known methods is to introduce another polymer into a polymer to generate immiscible blends. When the conductive filler is dispersed in one polymer phase, …

Advanced Carbon Materials Based Electrodes For High Performance Symmetric Supercapacitors, Keliang Wang

Electronic Theses and Dissertations

Supercapacitors have received considerable attention due to their high energy density, long life time, rapid charge/discharge rate, and because they are environmental friendly technology. Electrode materials play a key role in the final performance of supercapacitors. Carbon, usually used as symmetric supercapacitors electrode materials, exhibit extraordinary stability in harsh electrolyte and electrochemical performance owing to its physical and chemical properties. In addition, porous structure originated from activation, excellent electrical conductivity, sustainability, wide availability and low cost further offering the improvement in electrochemical performance and make it to be a promising electrode material for symmetric supercapacitors. Considering the factors affected electrochemical …

Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao

Electronic Theses and Dissertations

Butanol is considered a promising, infrastructure-compatible biofuel. Butanol has a higher energy content than ethanol and can be used in conventional gas engines without modifications. Unfortunately, the fermentation pathway for butanol production is restricted by its toxicity to the microbial strains used in the process. Butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Gas stripping technology can efficiently remove butanol from the fermentation broth as it is produced, thereby decreasing its inhibitory effects. Traditional butanol separation heavily depends on the energy intensive distillation method. One of the main issues in acetone-butanol-ethanol fermentation …

Successful Field Application Of A New Polymer Flooding Technique Suitable For Mature Oilfields Against Low-Oil-Price Background - A Case Study From East China, X. Wu, Y. Wu, C. Xiong, H. Xu, X. Jia, L. Shao, Y. Xiong, J. Zhang, A. Wang, H. Xu, J. Tian, Baojun Bai, X. Tian

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

DGXJ is a sandstone reservoir with temperature of 113 °C, salinity of 36235mg/L, and calcium and magnesium content of 1152mg/L and 30mg/L respectively. The reservoir is not only vertically multilayered and severe heterogeneous, but also witnesses water flowing channels, irregular and imperfect injecting production well patterns, high recovery degree (43%) and high water cut (97%). A new particle-type polymer (SMG) slug combined several small linked-polymer-gel (LPG)slugs and pregelled swellable particle (PSP) was applied during 2011-2015 and achieved remarkable technical and economic effect. The application area is composed of 16 injection wells and 22 production wells. Among the 22 wells, 17 …

Platinum Nanoparticles-Cobalt Oxide Nanostructures As Efficient Binary Catalyst For Ethylene Glycol Electro-Oxidation, Ghada El-Nowihy

Chemical Engineering

An enhanced electrocatalytic activity towards ethylene glycol oxidation reaction (EGO) in alkaline medium is observed at a glassy carbon (GC) electrode modified with a nanoparticle-based binary catalyst composed of Pt (nano-Pt) and cobalt oxide (nano-CoOx). The electrocatalytic activity of the modified electrodes towards EGO depends on the loading level as well as the composition of the catalyst layer atop the GC electrode surface. Several techniques including cyclic voltammetry (CV), field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) are used to address the catalytic activity of the proposed catalyst and to reveal their surface morphology and composition, respectively. …

Investigation Of Local Velocities And Phase Holdups, And Flow Regimes And Maldistribution Identification In A Trickle Bed Reactor, Mohd Fitri Bin Abdul Rahman

Doctoral Dissertations

"Trickle bed reactors are packed beds of catalyst on which gas and liquid reactants flow concurrently downward. In this work, the experimental work was carried out in 0.14 m diameter Plexiglas column using air-water system flowing over a packed bed of 3 mm glass bead particles. The local liquid and gas velocities, phase saturation and their time series have been investigated for the first time by developing, validating, and implementing a new two-tip optical fiber probe technique. It was found the radially and axially the liquid and gas velocities and their saturation vary and they also vary with times. In …

Mass Transfer Studies In Heavy Oil Recovery Using Solvents, Vijitha Mohan

Doctoral Dissertations

"Heavy oil, sometimes called bitumen, is known for its high viscosity (above 100 cp) and low API gravity (below 22⁰). In most cases, viscosity reduction is needed for the final product. There is a considerable amount of heavy oil in Alberta, Canada and the world's largest heavy oil deposit is in Venezuela. Yet less than 1% of it can be recovered because of its high viscosity. For shallow reservoirs, it is possible to resort to open cast mining. For deeper reservoirs, steam is used at ~ 350 ⁰C which gets the oil viscosity reduced to 1cp, which can now be …

Experimental Study Of Natural Convection Heat Transfer And Gaseous Dynamics From Dual-Channel Circulation Loop, Ibrahim Ahmed Said Abdallah

Doctoral Dissertations

"This research focuses on establishing a range of scaled separate and integral effects experiments for studying thermal-hydraulic behavior occurring within a component or region of the prismatic very high-temperature reactor (VHTR) such as plenum-to-plenum heat transfer and gaseous dynamics during natural circulation. Natural circulation of the coolant is the leading capability for VHTR to transport the decay heat from the core to the reactor vessel during accident scenarios. To address this need, a scaled-down facility is designed and developed with only two channels with upper and lower plena. The emphasis is placed on high-resolution and high-fidelity experimental data for local …