Materials Science and Engineering Commons^™

Six Years Of Service, Supply, And Success: Processing Harvested Ccr From Impoundments, William Fedorka, P.E.

World of Coal Ash Proceedings

No abstract provided.

Developing Single Use Deposits Of Coal Derived Fly Ash As A National Resource, Nigel Cooke

World of Coal Ash Proceedings

No abstract provided.

Relating Detonation Parameters To The Detonation Synthesis Of Silicon Carbide, Martin Langenderfer, Eric W. Bohannan, Jeremy Lee Watts, William Fahrenholtz, Catherine E. Johnson

Chemistry Faculty Research & Creative Works

Detonation synthesis of silicon carbide (SiC) nanoparticles from carbon liberated by negatively oxygen balanced explosives was evaluated in a 23 factorial design to determine the effects of three categorical experimental factors: (1) cyclotrimethylene-trinitramine (RDX)/2,4,6-trinitrotoluene (TNT) ratio, (2) silicon (Si) additive concentration, and (3) Si particle size. These factors were evaluated at low and high levels as they relate to the detonation performance of the explosive and the solid Si-containing phases produced. Detonation velocity and Chapman-Jouguet (C-J) detonation pressure, which were measured using rate stick plate dent tests, were evaluated. Solid detonation product mass, silicon carbide product concentration, and residual silicon …

Synthesis And Stabilization Of Gold Nanoparticles From Chloride And Cyanide Systems, Kathryn Ariela Bozer

Graduate Theses & Non-Theses

Generating gold nanoparticles (AuNPs) from gold chloride solution by precipitating with compounds can be difficult due to the potentially required high temperatures. Tin chloride can be used to overcome this dilemma. The process that is known to make Purple of Cassius is a method where gold chloride and tin chloride solutions are mixed to form AuNPs and tin oxide precipitate. However, it is modified by adding hydrazine to resolubilize the tin oxide and provide a more stable solution for the AuNPs. A three-factor central composite experimentally designed model was created using Design Expert incorporating pH, temperature, and gold concentration as …

Control Of High-Temperature Static And Transient Thermomechanical Behavior Of Simo Ductile Iron By Al Alloying, Semen Naumovich Lekakh, Catherine E. Johnson, L. Godlewski, Mei Li

Materials Science and Engineering Faculty Research & Creative Works

Silicon and molybdenum (SiMo) ductile iron is commonly used for exhaust manifolds because these components experience thermal cycling in oxidizing environment, which requires resistance to fatigue during transient thermomechanical loads. Previous studies have demonstrated that alloying elements, such as Al, to SiMo ductile iron reduces the amount of surface degradation during static high-temperature exposure. However, deterioration of sphericity of the graphite nodules and a decrease in ductility could affect the tendency of cracking during thermal cycling. In this article, the effect of Al alloying on static and transient thermomechanical behavior of SiMo ductile iron was investigated to optimize the amount …

Detonation Synthesis Of Nanoscale Silicon Carbide From Elemental Silicon, Martin J. Langenderfer, Yue Zhou, Jeremy Lee Watts, William Fahrenholtz, Catherine E. Johnson

Materials Science and Engineering Faculty Research & Creative Works

Direct reaction of precursors with the products of detonation remains an underexplored area in the ever-growing body of detonation synthesis literature. This study demonstrated the synthesis of silicon carbide during detonation by reaction of elemental silicon with carbon products formed from detonation of RDX/TNT mixtures. Continuum scale simulation of the detonation showed that energy transfer by the detonation wave was completed within 2–9 μs depending on location of measurement within the detonating explosive charge. The simulated environment in the detonation product flow beyond the Chapman-Jouguet condition where pressure approaches 27 GPa and temperatures reach 3300 K was thermodynamically suitable for …

Calcite Depression In Bastnaesite-Calcite Flotation System Using Organic Acids, Emmy Muhoza

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bastnaesite is the primary source of light REEs, namely cerium (Ce), lanthanum (La), praseodymium (Pr), neodymium (Nd), to name a few. Bastnaesite is typically concentrated using the froth flotation beneficiation method. Flotation of bastnaesite suffers from high reagent consumption due to the similar surface characteristics of bastnaesite and associated gangue minerals, including calcite. Additionally, complex stages of high-temperature conditioning are often required to suppress the detrimental impact of dissolved calcium ions on the flotation of bastnaesite. This research seeks to investigate the capabilities of organic acids in the bastnaesite-calcite flotation systems to selectively depress calcite minerals and effectively chelate calcium …

Findings Report: Virtual Workshop On ‘Resilient Supply Of Critical Minerals’, Marek Locmelis, Angela D. Lueking, Michael S. Moats, Kwame Awuah-Offei, Lana Z. Alagha, Mark W. Fitch, Alanna Krolikowski, Shelby Clark

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Executive Summary
On August 2-3, 2021, the Thomas J. O’Keefe Institute for Sustainable Supply of Strategic Minerals at Missouri University of Science and Technology (Missouri S&T) hosted the NSF-funded virtual workshop ‘Resilient Supply of Critical Minerals’. The workshop was convened via Zoom and attracted 158 registrants, including 108 registrants from academia (61 students), 30 registrants from government agencies, and 20 registrants from the private sector. Four topical sessions were covered:

A. Mineral Exploration and Source Diversification.
B. Supply Chain and Policy Issues.
C. Improving Mineral Recycling and Reprocessing Technologies.
D. Technological Alternatives to Critical Minerals.

Each topical session was composed …

Assessment Of Heavy Metal Concentration In Soils Around Geita The Gold Mine, Tanzania, Mariam G. Mgendi, Mkabwa L. K Manoko, W.J.S. Mwegoha, C. Southway C. Southway

Journal of Humanities and Social Sciences

Health issues related to gold mining cannot be underestimated. Gold mining produce acid mine drainage (AMD), which in turn releases heavy metals into the nearby environment, hence causing environmental pollution. Heavy metals are naturally very toxic, thus pose a great health concern especially when their concentration exceeds the recommended permissible limits. In this study, concentrations of five heavy metals—including Pb, Ni, Cr, Cu and Zn—were assessed in the soil around Geita Gold Mine (GGM). A total of 17 sampling sites were established from which the soil samples were collected at 0-15cm and 15-30cm soil depth. The concentration of both total …

Modeling Of Rare Earth Solvent Extraction Process For Flowsheet Design And Optimization, Vaibhav Kumar Srivastava

Theses and Dissertations--Mining Engineering

The separation and purification of rare earth elements (REEs) into individual products has been a topic of significant interest for researchers and engineers for many decades. The prime reason for such sustained interest is due to REEs’ demand and application in modern technology, as well as the challenges associated with their separation and purification. The chemical similarity of rare earth group elements is responsible for difficult separability which makes purification of individual elements challenging. Despite associated complications, processes such as solvent extraction (SX) and ion-exchange have been successfully utilized in the separation and production of REEs on pilot and commercial …

The Effects Of Rigid Polyurethane Foam As A Confinement Material On Breaching Charge Detonations, Nathan Franz Paerschke-O'Brien

Masters Theses

"The effects of a rigid polyurethane foam used as a confinement material on four types of breaching explosives were tested, focusing on the changes in shockwave peak pressures, detonation load compression forces, and brisance cratering abilities. The Plate Dent testing procedure was modified to incorporate a load cell force sensor, and two air overpressure sensors were included adjacent to the blast to quantify each test result. The testing variables focused on the polyurethane foam cure times and thickness volumes around the breaching explosives to determine the breaching charges' optimal energy output capabilities when confined by the foam material. The rigid …

Recovery Of Phosphorus From Florida Phosphatic Waste Clay, Amir Eskanlou

Graduate Theses, Dissertations, and Problem Reports (ETD)

This MS thesis examines the recovery of phosphorus (P) from Florida waste clay (WC). A comprehensive literature review revealed that: (i)-The most important values being lost to WC are P and rare earth elements (REEs). For the recovery of these values from WC, two crucial attempts are the removal of extremely fine-sized clays, followed by the recovery of phosphate content, which can pave the path for the recovery of REEs; (ii)-Any scientific/ technological solution should, at the same time, be economically and environmentally attractive to the industry. As such, moving from mostly chemical separation processes to the primarily physical/ physicochemical …

Relating Detonation Parameters To The Detonation Synthesis Of Nanomaterials, Martin Langenderfer

Doctoral Dissertations

“This research investigates the physical and chemical processes that contribute to the detonation synthesis of silicon carbide nanoparticles. Bulk production of SiC nanoparticles through detonation is possible due to pressures achieved over 20 GPa and temperatures over 2000 K as well as quenching rates in excess of 13 billion K/second. These conditions catalyze reaction and bottom-up molecular growth while retaining particles < 100 nm in diameter. In this work, detonation synthesis of SiC was demonstrated by incorporation of polycarbosilane, an SiC precursor material, into an RDX/TNT explosive matrix prior to detonation. Detonation Synthesis of SiC was also accomplished by reacting elemental silicon with carbon liberated by the detonation of negatively oxygen balanced TNT. Hydrodynamic simulation of a 60:40 mass ratio RDX/TNT detonation created conditions thermodynamically suitable to produce cubic silicon carbide within the first 500 nanoseconds after the passage of the detonation wave while carbon remains chemically reactive for molecular formation. Simulations and experimental tests indicated that loading configuration and impedance mismatch of the precursor additives used in detonation synthesis results in conditions in the additives that exceed the accepted detonation pressure of the explosive by greater than three times. Finally, a full factorial experimental design showed increasing silicon concentration, reducing silicon size, and reducing oxygen balance by adjusting the ratio of RDX to TNT decreased the explosives detonation pressure by 20% and increased the soot yield and concentration of SiC observed in the detonation products by 82% and 442% respectively”--Abstract, page iv.

Effects Of Inert Additives On Cyclotrimethylene-Trinitramine (Rdx)/Trinitrotoluene (Tnt) Detonation Parameters To Predict Detonation Synthesis Phase Production, Martin Langenderfer, William Fahrenholtz, Catherine E. Johnson

Materials Science and Engineering Faculty Research & Creative Works

A methodology was developed to predict pressure and temperature regimes achieved during detonation of RDX/TNT compositions with inert granular inclusions. The predicted pressures and temperatures are used as inputs for thermochemical simulations to design detonation synthesis experiments that utilize shock-induced chemical reactions to produce ceramic nanomaterials. This study computationally assessed the effects of inert spherical sand inclusions and porosity produced by inert additives on the sensitivity of the explosive composition during the shock-to-detonation transition using a limited scope approach through Lee-Tarver ignition and growth modeling. On the continuum scale, the effects of inert additives on pressure generation behind the detonation …

Framing Energy And Minerals For Future Pathways, Michelle Michot Foss, Michael S. Moats, Kwame Awuah-Offei

Materials Science and Engineering Faculty Research & Creative Works

We present a challenge for Group of Twenty (G20) discussions that entails (1) greater awareness of the role of non-fuel minerals in the global economy overall, but specifically in the energy sector; and (2) the introduction and acceleration of alternative energy sources and technologies. We focus on chemical battery energy storage, given its prominence in all views and outlooks of energy futures, especially for mobility. We present recommendations for G20 discussions and actions on battery materials, and the crucial underlying supply chains for mineral commodities.

Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha

Materials Science and Engineering Faculty Research & Creative Works

Froth flotation process is extensively used for selective separation of base metal sulfides from uneconomic mineral resources. Reliable prediction of process outcomes (metal recovery and grade) is vital to ensure peak performance. This work employs an innovative hybrid machine learning (ML) model—constructed by combining the random forest model and the firefly algorithm—to predict froth flotation efficiency of galena and chalcopyrite in relation to various experimental process parameters. The hybrid model's prediction performance was rigorously evaluated and compared against four different standalone ML models. The outcomes of this study illustrate that the hybrid ML model has the prediction ability to process …

On The Investigation Of Hot Tearing Behavior Of Continuous Cast Steel, Yanru Lu

Masters Theses

”Hot tearing has long been recognized as a major problem that plagues the development of the continuous casting process and results in low-quality products. Understanding of the mechanisms and the required conditions for the hot tearing formation is important for industries but has not been well-established yet. Thus, this research focuses on the hot tearing issue observed in continuous cast steel, by providing a summary of the current research progress and then introducing a new laboratory method to determine the thermo-mechanical properties relevant to hot tearing of different steel grades under different solidification conditions. In this method, an apparatus was …

Using Numerical Models Of Dewatering At Coal Ash Impoundments To Understand Cost And Schedule, Peter Bell, Joel Thompson, Don Fuller

World of Coal Ash Proceedings

No abstract provided.

Investigating Ccr Units And Evaluating The Physical Properties Of Ponded Ccr, David Skeggs, Zahra Aghazadeh, Rachel Combs

World of Coal Ash Proceedings

No abstract provided.

Demonstration Of “No Migration” Alternative Performance Standard For Ccr Facilities In Arid To Semi- Arid Regions Using Unsaturated Zone Modeling, James Aiken, Katy Lindstom

World of Coal Ash Proceedings

No abstract provided.

State Vs Federal Ccr Rule Regulations: Comparisons And Impacts, Nicole Kron, Eric Nelson

World of Coal Ash Proceedings

No abstract provided.

Coal Combustion Residuals Management Using Geotextile Containers- Considerations For Various Options, Randall Wilcox, Gregg Lebster, Bryan Hamilton, Thomas Stephens

World of Coal Ash Proceedings

No abstract provided.

Continuous, Real-Time Tss Monitoring Verifies Effluent Quality And Coal Ash Management Performance While Reducing Compliance Costs, Dave Fraley, Chris Bauman, Dave Donahue

World of Coal Ash Proceedings

No abstract provided.

Effect Of Coal Fly Ash On Agricultural Crops :Second Phase Showcase Project On Use Of Fly Ash In Agriculture In And Around Thermal Power Station Areas Of National Thermal Power Corporation Ltd., India., K. Arivazhagan, M. Ravichandran, S.K. Dube, V.K. Mathur

World of Coal Ash Proceedings

No abstract provided.

Advantages Of Single Source Contracting In-Plant Ccr Services, Kevin Foody, Marcella Funderburg, Blake Whittington

World of Coal Ash Proceedings

No abstract provided.

Design And Construction Of A Ccr Landfill Adjacent To The Missouri River, Thomas Gredell, Jeffrey Fouse, Jay Ellington

World of Coal Ash Proceedings

No abstract provided.

Geochemical Tools For Groundwater Monitoring At Coal Fired Utilities, Jeff Gillow, Bruce Sass, Hari Parthasarathy

World of Coal Ash Proceedings

No abstract provided.

Bottom Ash Handling Conversions – Lessons Learned, Dustin Doerr

World of Coal Ash Proceedings

No abstract provided.

Encapsulation Of Thermoevaporation Brines Using Coal Combustion Residuals, Dale Prentice, Kirk Ellison, Gaurav Sant

World of Coal Ash Proceedings

No abstract provided.

Recycling Of Coal Ash In Agriculture: Use Of Vermicomposting Biotechnology, G.N. Chattopadhyay, Gourab Roy, Wasim Iftikar

World of Coal Ash Proceedings

No abstract provided.