Engineering Commons^™

Hydrothermal Liquefaction (Htl) Of Lignocellulosic Biomass For Biocrude Production: Reaction Kinetics And Corrosion-Resistance Performance Of Candidate Alloys For Reactors, Haoyu Wang

Electronic Thesis and Dissertation Repository

In recent years, the rapid increase in the demand for clean energy and green chemicals as well as concerns over the supply and environmental impacts associated with fossil. resources have stimulated intensive research on conversion of bioresources, such as lignocellulosic biomass and biowaste, into energy, fuels, chemicals, and materials.

Hydrothermal liquefaction (HTL) is a unique thermochemical conversion process, particularly applicable for the conversion of wet biomass and biowaste feedstocks. Most of the biomass HTL studies are conducted in batch reactor and focus on the effects of catalysts, reaction temperature and time on production efficiency and chemical properties of the products. …

The Study Of Copper Corrosion Mechanisms Using Electrochemical Experimental Techniques., Evan Grimm

Electronic Theses and Dissertations

The purpose of this study was to discover and thoroughly explain the corrosion mechanisms of copper in saltwater, tap water and deionized water, and to apply these methods and findings when testing the corrosion mechanisms of other materials. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, and Tafel analysis.

The copper was found to corrode at a greater rate in saltwater, followed by tap water then deionized water, with a larger difference between saltwater and tap water than between tap water and deionized water. Each reaction was found to be both kinetically …

Increasing The Corrosion Protection Of Aisi 1008 Carbon Steel By Surface Treatment With Unmodified And Benzotriazole Modified Sol-Gel Films, Shane Thomas Kelliher

Williams Honors College, Honors Research Projects

The corrosion performance of sol-gel coated AISI 1008 carbon steel was investigated in 3.5 wt% NaCl solutions of pH 7, 9, and 12 using electrochemical measurements. A corrosion inhibitor, benzotriazole (BTA) was added to the sol-gel mixture and tested as a second, modified sol-gel coating. Sol-gel films adhered evenly to metal samples and were characterized by FTIR spectroscopy. Electrochemical Impedance Spectroscopy (EIS) showed an increase in polarization resistance from blank to sol-gel coated samples (600-18,800,000 ohms). Cyclic polarization (CPP) curves showed positive hysteresis loops for blank and unmodified sol-gel coated samples which increased at high pH following the backward potential …

Aqueous Redox Flow Batteries With Boron Doped Diamond As An Electrode., Alex M. Bates

Electronic Theses and Dissertations

As the interest and implementation of renewable energy accelerates, so does that of grid energy storage. It is widely believed that a cost-effective energy storage technology will bring about the proliferation of renewable energy. Redox flow battery (RFB) technology represents a promising solution to cost-effective grid energy storage. Compared to other technologies, RFBs have a long lifetime, high efficiency, are non-flammable, significantly reduce cost, and separately scale power and energy. The separation of power and energy enables increased energy capacity by simply adding electrolyte volume. Of the challenges facing RFB technology, one readily apparent is the cost of the active …

Testing The Effectiveness Of Reflective "Cool" Pigments, Ashleigh Carpenter

Williams Honors College, Honors Research Projects

This project is an exploration of reflective "cooling" pigments used in coatings for the exterior of a structure in order to control the temperature inside. The pigments reflect sunlight to reduce the heating effect inside a structure. While the project will include the synthesis and testing of these pigments, the focus will be on the design and construction of an apparatus to test the effectiveness of these pigments. An apparatus will be constructed with a heat source and two structures of identical dimensions. The set-up will allow for the temperature of the inside of the structures to be recorded at …

Cataloging The Degree Of Sensitization Via Electrochemical Reactivation For Studying The Corrosion Behavior Of Inconel 718, Austenitic, And Duplex Stainless Steels, Bradley Lynes

Williams Honors College, Honors Research Projects

Corrosion resistant materials can be expensive, but usually reduce the life cycle cost of metallic assets. However, negligent sensitization of these materials can lead to aggressive, intergranular corrosion. Using the methodology of the double loop electrochemical potentiokinetic reactivation (DL-EPR), this project investigates different steel reinforced bars and Inconel to determine the degree of sensitization after a heat treatment of 900°C for 2 hours. The purpose of this research is to validate and determine the appropriate test parameters for performing further DL-EPR test in the future. Additionally, the kinetics observed for each sample during the DL-EPR test will be analyzed and …

Evaluation Of Silane-Doped Epoxy Coatings For Resisting Aluminum Corrosion By Oxalic Acid, An A. Niger Metabolite, Alex Pica

Williams Honors College, Honors Research Projects

The goal of this study was to investigate whether silane-doped epoxy coatings are capable of preventing corrosion of aluminum alloy 2024-T3 by oxalic acid, one of the primary metabolites of the fungus Aspergillus Niger. Previous research suggested the success of these types of coatings at preventing AA 2024-T3 corrosion in saline solutions, and this study was meant to build on those findings by investigating the efficacy of the coating in an acidic environment.

Each coating was applied to an AA 2024-T3 coupon by dissolving the epoxy and varying amounts of 3-aminopropyltriethoxysilane in acetone and then dripping the solution onto …

The Effects Of Carboxylic Acids In Aluminum Anodizing, Abby E. Koczera

Honors Theses and Capstones

Hard-anodized alumina coatings were formed in sulfuric acid at low temperature and high current density in the presence of carboxylic acid additives. Citric acid, trimesic acid, mellitic acid and ethylenediaminetetraacetic acid (EDTA) were utilized in varying concentrations. The additives were chosen for their capacity to form complexes with tri-valent aluminum and hence impart chemical stability to the coatings. The coatings were sealed in boiling water, and corrosion resistance was observed in a high pH solution of potassium hydroxide. The coatings were examined using scanning electron microscopy (SEM) to assess coating thickness and pore dimensions. Thicker coatings were produced when the …

Corrosion Resistance Of Silane Coatings On Aluminum And Magnesium Alloys, John Demopoulos

Williams Honors College, Honors Research Projects

The purpose of this project was to increase the corrosion resistance of aluminum and magnesium alloys by coating the coupons with a silane on the surface. Four different silanes: 3-aminopropyltriethoxysilane (APTES), Bis(triethoxysilylpropyl)amine (Bis), (Heptadecafluoro-1,1,2,2-tetrahydrodecyl)trichlorosilane (FTS), and (Heptadecafluoro-1,1,2,2-tetrahydrodecyl)triethoxysilane (non Cl FTS) will be used and compared to see which silane would give the best corrosion resistance. Each silane solution was coated on the coupons by using a solution method in which the coupon was submerged for 24 hours and then thermally cured for another 24 hours. Once the coating was applied, the water contact angle and the thickness of the coating …

Passivation And Potential Fluctuation Of Az31b Alloy In Alkaline Environments, Ana C. Bacco

Williams Honors College, Honors Research Projects

Magnesium (Mg) alloys are used in many industries because of their distinctive properties, but their high chemical reactivity and poor oxide film protection make them inferior. This project focused on investigating the effects of secondary phases and intermetallic particles (IMPs) on the corrosion behavior of AZ31B Mg alloy. The test solution was chloride free NaOH with varying pH levels between 10-14, as well as testing under deaerated conditions. The open circuit potential (OCP) measurements using AZ31B in static NaOH solutions showed potential fluctuation between approximately -1.6 V_SCE (active state) and -0.4 V_SCE (passive state) during the 24-h immersion. …

Swelling-Etching Characterization Of Copper (I) Oxide - Pdms For The Development Of Micro/Nano - Particles Composite Mems Corrosion Sensor, Abdoul Kader Maiga

Graduate Theses and Dissertations

The primary objective for this thesis is to contribute to the understanding of the oxide removal process for a corrosion sensing device. The goal for designing such a device is for monitoring corrosion on metallic structures. The sensing material (6.35mm x 1mm discs) of the device is composed of copper (I) oxide particles mixed in some polydimethylsiloxane (PDMS). The PDMS, “housing,” is meant for controlling the oxidation rate through the sensing material. A solvent was used to facilitate the etchant diffusion through the PDMS matrix. Toluene and acetic acid were the ideal solvent and etchant, respectively, for carrying out the …