Chemical Engineering Commons^™

Micro Hydroelectric Power Generation, Roberto Arraya Saenz

Chemical Engineering Undergraduate Honors Theses

MICRO-HYDRO ELECTRIC POWER GENERATION Roberto Arraya Department of Chemical Engineering – Honors Thesis ABSTRACT A major industrial water user in New Mexico discharges approximately 3.8 million gal of wastewater per day. The topology of the site provides an elevation difference of about 150 ft between the plant site and the entrance to the municipal sewage line; this flow and elevation difference is sufficient to produce about 40 kW of electrical power using a water turbine/electrical generator set to extract power from the flowing stream. This report includes designs and economic analyses for two distinct cases. One case is based on …

Purification Of Fibrinogen From Human Plasma, Ayman E. Ismail

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

A solvent detergent treated fibrinogen was purified from human plasma by cryoprecipitation (cryo) followed by chemical precipitation using ethanol (EtOH) or ammonium sulfate (AS) as precipitating agents. Amounts of fibronectin (FN), factor XIII A-subunit (FXIIIA), factor XIII b-subunit (FXIIIB), and alpha₂-antiplasmin (α₂-AP) in the isolated fibrinogen were quantified. Thromboelastography (TEG) analysis was used to evaluate the clot strength of the isolated fibrinogen and to determine the ability of the ethanol and ammonium sulfate precipitations to eliminate the solvent detergent. Sodium dodecylsulfate-polyacrylamide gel analysis indicated that fibrinogen produced by each of these precipitation methods had similar purity. …

Design Of Advanced Fouling-Resistant And Self-Cleaning Membranes For Treatment Of Oily And Impaired Waters, Daniel Wandera

All Dissertations

The overall goal of my Doctor of Philosophy (PhD) research was to design and develop advanced anti-fouling and self-cleaning membranes for treating impaired waters. Initial work focused on the development of membranes to treat produced water, which is oily wastewater that is co-produced during oil and gas exploration. Economical, environmentally sustainable treatment of the large volumes of produced water is a grand challenge for oil and gas companies. While membranes offer many advantages over more conventional treatment methods, membrane-based treatment processes for oily waters often fail due to membrane fouling. Therefore, the primary objective of my doctoral research was to …

Characterization And Quantification Of Monomers, Oligomers, And By-Products From Xylan During Biomass Pretreatment, Ching-Shuan Lau

Graduate Theses and Dissertations

Biomass pretreatment generates inhibitory products, which reduce the overall yield of xylose for ethanol production. Understanding of hemicellulose depolymerization into xylose is essential to identify the pretreatment conditions that maximize xylose formation, but minimize the generation of these inhibitory products, such as formic acid and furfural. Thus, the goal of this project is to understand how dilute acid pretreatment parameters affect hemicellulose depolymerization, maximize xylose concentrations, and minimize by-products formation.

To progress towards this goal, rates and mechanisms of hemicellulose release must be determined. Birchwood xylan was used as the starting material to produce xylose oligomers. The hydrolyzed birchwood xylan …

Optimization Of A Dynamic Hot Water Pretreatment Of Switchgrass Using Catalysis By Carbonation To Maximize Carbochemical Yields, Rohit Tanaji Dhamdere

Graduate Theses and Dissertations

A bio-refinery is a facility that converts renewable bio-resources into value-added chemicals and products. In this context of a bio-refinery, the production of the carbochemicals such as HMF, furfural and organic acids illustrate that multiple products can be produced from a renewable source such as lignocellulosic biomass (switchgrass). Traditionally, carbochemicals such as furfural and HMF are produced using inorganic acids such as H2SO4, HCL, and H3PO4. The use of such acids requires the application of high cost materials of construction such as Hastelloy-C, titanium etc.

The objective of this study is to develop a semi-continuous process for the conversion of …

Adsorption Kinetics Of Pb(Ii) And Zn(Ii) Ions Unto Carbonized Groundnut Shells And Maize Cobs, Leke Luter, Aboi Julius, Henry T. Dekaa, B. A. Ikyenge, Ande Sesugh, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Maize cobs and groundnut shell adsorbents from agricultural by-products were carbonized and investigated for adsorption of two selected metals, Lead (Pb II) and Zinc (Zn II) from aqueous solutions of these metals. Kinetic studies of the adsorption processes were investigated employing Elovich and the intraparticle diffussion models. The results showed that, the adsorption capacities of these comparatively cheaper adsorbents and their efficiency for the removal of Pb(II) and Zn(II) ions from aqueous solution present them suitable for use in place of the costly commercial activated carbons.

Gallium Containing Glass Polyalkenoate Anti-Cancerous Bone Cements: Glass Characterization And Physical Properties, A. W. Wren, A. Coughlan, L. Placek, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

A gallium (Ga) glass series (0.48SiO₂-0.40ZnO-0.12CaO, with 0.08 mol% substitution for ZnO) was developed to formulate a Ga-containing Glass Polyalkenoate Cement (GPC) series. Network connectivity (NC) and X-ray Photoelectron Spectroscopy (XPS) was employed to investigate the role of Ga³⁺ in the glass, where it is assumed to act as a network modifier. Ga-GPC series was formulated with E9 and E11 polyacrylic acid (PAA) at 50, 55 and 60 wt% additions. E11 working times (T_w) ranged from 68 to 96 s (Lcon.) and 106 s for the Ga-GPCs (LGa-1 and LGa-2). Setting times (T_s) …

Processes For The Production Of Buprenorphine With Reduced Impurity Formation, Brenda E. Allen, Esa T. Jarvi, Dennis J. Kaluta, James R. Meyer, Keith Tomazi, Anthony Mannino, Brian Orr

Chemical and Biochemical Engineering Faculty Research & Creative Works

The present invention provides process for the production of opiate alkaloids. In particular, the present invention provides processes for the production of buprenorphine or a derivative of buprenorphine that minimizes the formation of impurities.

Solid Oxide Fuel Cells With Both High Voltage And Power Output By Utilizing Beneficial Interfacial Reaction, Chao Su, Zongping Shao, Ye Lin, Yuzhou Wu, Huanting Wang

Faculty Publications

An intriguing cell concept by applying proton-conducting oxide as the ionic conducting phase in the anode and taking advantage of beneficial interfacial reaction between anode and electrolyte is proposed to successfully achieve both high open circuit voltage (OCV) and power output for SOFCs with thin-film samarium doped ceria (SDC) electrolyte at temperatures higher than 600 °C. The fuel cells were fabricated by conventional route without introducing an additional processing step. A very thin and dense interfacial layer (2–3 μm) with compositional gradient was created by in situ reaction between anode and electrolyte although the anode substrate had high surface roughness …

Homogeneous Viologens For Use As Catalysts In Direct Carbohydrate Fuel Cells, Dane C. Hansen

Theses and Dissertations

Deriving electrical energy from glucose and other carbohydrates under mild conditions is an important research objective because these biomolecules are abundant, renewable, and can provide 12 to 24 electrons per molecule, yielding substantial electrical power. It was previously observed that disubstituted viologens, salts of N,N'-disubstituted 4,4'-bipyridine, are able to oxidize glucose under alkaline conditions. Building on that initial result, the objective of this work was to understand and quantify the effectiveness and utility of viologens as catalysts for use in direct carbohydrate fuel cells.The extent that viologens oxidize carbohydrates, the conditions under which that oxidation occurs, and the mechanism for …

Order-Disorder Transition Of Aragonite Nanoparticles In Nacre, Zaiwang Huang, Xiaodong Li

Faculty Publications

Understanding nacre’s bottom-up biomineralization mechanism, particularly, how individual aragonite platelets are formed, has long remained elusive due to its crystallographic peculiarity and structural complexity. Here we report that crystallographic order-disorder transition can be triggered within individual aragonite platelets in pristine nacre by means of heat treatment and/or inelastic deformation, offering a unique opportunity to discriminate mysterious aragonite nanoparticles in transmission electron microscopy. Our findings unambiguously uncover why aragonite nanoparticles in pristine nacre have long been inaccessible under TEM observation, which is attributed to the monocrystal-polycrystal duality of the aragonite platelet. The underlying physical mechanism for why an individual aragonite platelet …

Transparent Conducting Films Of Cdse(Zns) Core(Shell) Quantum Dot Xerogels, Lasantha Korala, Li Li, Stephanie L. Brock

Chemistry Faculty Research Publications

A method of fabricating sol–gel quantum dot (QD) films is demonstrated, and their optical, structural and electrical properties are evaluated. The CdSe(ZnS) xerogel films remain quantum confined, yet are highly conductive (10⁻³ S cm⁻¹). This approach provides a pathway for the exploitation of QD gels in optoelectronic applications.

Constrained Control And Optimization Of Tubular Solid Oxide Fuel Cells For Extending Cell Lifetime, Ben Spivey, John Hedengren, Thomas F. Edgar

Faculty Publications

Extending fuel cell lifetime is a necessary objective for reducing fuel cell power generation cost of electricity. Capital costs comprise the most significant fraction of the cost of electricity. Reducing the frequency of fuel cell replacement can be achieved by implementing a control strategy that prevents excursions into operating regions causing failure. In this paper we implement a constrained MIMO model predictive controller (MPC) to avoid the failure modes relevant for a high-temperature tubular solid oxide fuel cell (SOFC) system while performing load-following. The primary causes of failure are catalyst poisoning, fuel or air starvation, carbon deposition, and microcracking. Prior …

Computational Modeling Of Functionalized Carbon Nanotubes, Nathaniel Lee Miller

Theses and Dissertations

Ab initio self-consistent field (SCF) molecular orbital calculations were performed employing various basis sets to computationally predict methods to functionalize and solubilize carbon nanotubes. The structure and Restricted Hartree-Fock (RHF) or “total” energies of functionalized nanotubes of various configurations were determined via theoretical calculations. Total energies were used to determine preferences for adsorption on nanotube sur-faces. Various diameter carbon nanotubes (CNTs) were tested to determine where a transition from a non-wrapping to a wrapping approach was found likely to occur as a function of diameter. Further refinements to this method could be used to explore additional interactions as nanotube diameter …

An Oxidase-Based Electrochemical Fluidic Sensor With High-Sensitivity And Low-Interference By On-Chip Oxygen Manipulation, Nitin Radhakrishnan, Jongwon Park, Chang Soo Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Utilizing a simple fluidic structure, we demonstrate the improved performance of oxidase-Based enzymatic biosensors. Electrolysis of water is utilized to generate bubbles to manipulate the oxygen microenvironment close to the biosensor in a fluidic channel. for the proper enzyme reactions to occur, a simple mechanical procedure of manipulating bubbles was developed to maximize the oxygen level while minimizing the pH change after electrolysis. the sensors show improved sensitivities based on the oxygen dependency of enzyme reaction. in addition, this oxygen-rich operation minimizes the ratio of electrochemical interference signal by ascorbic acid during sensor operation (i.e., amperometric detection of hydrogen peroxide). …

Examination Of The Migratory Potential Of Patterned Cortical Neurons Using Laser Direct-Write, T. B. Phamduy, C. J. Rivet, D. Kingsley, R. J. Gilbert, D. B. Chrisey

Chemical and Biochemical Engineering Faculty Research & Creative Works

We describe the patterning of neuronal cultures by a laser-based printing system. Embryonic chick cortical neurons were transferred into predetermined array positions with micron accuracy, enabling detailed study of neuronal migration, aggregation, and neurite outgrowth regulated by cell-cell interactions on a homogeneous surface. Images of cells were analyzed up to 14 days. Results demonstrated that increasing the spacing between neighboring groups of cells causes intra-group cells to preferentially migrate towards each other and aggregate towards the center of the printed 'spot'. In addition, increasing the printed 'spot' size encouraged migration towards neighboring groups of cells. © 2012 IEEE.

The Structural Characterization Of Ga 2o 3-Na 2o-Cao-Zno-Sio 2 Bioactive Glasses, T. J. Keenan, A. W. Wren, A. Coughlan, M. M. Hall, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The characterization of bioactive glasses in which zinc (Zn) has been incrementally replaced by gallium (Ga). © 2012 IEEE.

Silver Coated Bioactive Glass Particles For Wound Healing Applications, P. Hassanzadeh, A. W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hench and colleagues discovered that bone could bond chemically to certain glass compositions in 1969 [1]. This group of glasses is known as bioactive glasses [1]. Some special compositions of bioactive glasses will bond to soft tissues as well as bone [1]. One of the important characteristics of bioactive glasses is their ability to release beneficial ions such as Ca²⁺, Na⁺, Zn²⁺, Sr²⁺, and PO 43- in the body, which promote self-healing [2]. Bioactive glasses generally contain much less glass former (e.g., SiO₂, B₂O₃ etc.) than conventional …

Increasing The Quantity Of Silver In Zinc-Based Glass Polyalkenoate Cement: Is There An Improvement In Antibacterial Efficacy?, A. Coughlan, S. M. Breed, C. Ashraf, J. A. Cardinale, M. M. Hall, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone cements should have the ability to chemically bond to both bone and surgical metals, exhibit no chemical or thermal necrosis, and have no significant shrinkage or exotherm upon setting. Taking these properties into consideration, glass polyalkenoate cements (GPCs) have potential as bone cements. GPCs are formed by the reaction between an ion-leachable glass and an aqueous solution of polyacrylic acid (PAA) [1] and have proven antibacterial and cariostatic properties [2], which are related to their ability to release beneficial amounts of ions over time [3, 4]. The GPCs can be formulated to release ions that can have a therapeutic …

Gallium Containing Glass Polyalkenoate Bone Cements: Glass Characterization And Physical Properties, L. Placek, A. W. Wren, A. Coughlan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Gallium (Ga) glasses were developed to formulate a Glass Polyalkenoate Cement (GPC) series with both E9 and E11 polyacrylic acid (PAA) at 50, 55 and 60wt% additions. Working times (T w), setting times (T s), compression (σ c), and biaxial flexural (σ f) strength testing were evaluated to determine the GPCs potential use in orthopedics. © 2012 IEEE.