Engineering Commons^™

Effects Of Magnetite Particle Morphology On Adsorption Of Copper Ions From Aqueous Solutions, Alisa Hashley

Graduate Theses & Non-Theses

Adsorptive processes can be used for metal contaminant removal. This work addresses magnetite, a magnetic iron oxide, as the adsorbent for use in an adsorptive removal system, known as the continuous flow material recovery system (CFMR), developed by Leitzke et al. [1]. Though the system is effective in removing contaminants from aqueous solution, efforts to further improve efficiency are being made. One way to improve the efficiency of the CFMR is to analyze the magnetite particles being used and investigate how the particle properties effect adsorption. The author’s research is presented and discussed here to describe the effects magnetite particle …

A Guide To Fifty Years Of Research At Montana Tech: Part 3-Decontamination Of Ratioactively Contaminated Steel By Melt Refining/Slagging Processing, Larry G. Twidwell, Samuel A. Worcester

Metallurgy

This presentation includes a discussion of the research conducted at Montana Tech in the Department of Metallurgical and Materials Engineering. The discussion is focused on Decontamination of Radioactively Contaminated Steel by Melt Refining/Slagging. This presentation is based on the research of Master of Science graduate students, industrial and academic colleagues, at the Montana College of Mineral Science and Technology (which morphed to Montana Tech [1977], then to Montana Tech of The University of Montana [2000], then to Montana Technological University [2019]). The referenced work of each of the graduate students in this presentation is gratefully acknowledged. The following summary presentation …

A Study Of Biochar Production Via Continuous Vacuum-Assisted Pyrolysis, Max Wohlgenant

Graduate Theses & Non-Theses

The present study focuses upon the design, fabrication, and feasibility of the bulk production of scientific biochar for mobile delivery. In the 2022 annual report, the National Academies of Science, Engineering, and Medicine recommended the integration of mobile, decentralized reactors that employ flexible manufacturing and circular economic principles. Biochar production, involving the thermal degradation of biomass under an inert atmosphere to yield remediation media is an ideal material to satisfy this recommendation. Many potential application sites, such as abandoned mines, are remote and limit the construction of large infrastructure. The continuous vacuum-assisted pyrolysis (CVAP) reactor was designed to: increase biochar …

Optimization Of Porosity In Cold Spray Produced Copper And Zinc Coatings, Cameron Hughes

Graduate Theses & Non-Theses

Since its invention in 1981, the cold spray (CS) additive manufacturing (AM) process has been studied and optimized to produce well-adhered, dense material coatings. CS can operate at a wide range of temperatures if the feed material remains in a solid state. Copper and zinc were studied to characterize and understand the effects of heating element voltage, travel speed, and standoff distance on deposit porosity, grain size, microhardness, and coating thickness. Samples were sprayed on 3.2 mm x 25 mm x 150 mm 6061 aluminum substrates. Sections were taken from the middle of the samples to represent steady-state conditions. Sample …

High-Pressure Slurry Ablation For Improving Separation Of Copper/Molybdenum And Flotation Of Gold Tailings, Mitchell Harvey

Graduate Theses & Non-Theses

Disa Technologies’ High-Pressure Slurry Ablation (HPSA) is a patented particle attrition technology for the comminution and selective liberation of minerals. Two slurry streams are pumped at high pressure through opposing nozzles and collisions between solid particles suspended in the slurry streams cause breakage of the feed material. HPSA was evaluated for improving the rougher flotation of molybdenite from Cu-Mo bulk concentrate and gold-bearing pyrite from gold tailings.

Copper/molybdenum samples were provided by Montana Resources in Butte, Montana. A two-factor factorial design of experiments was used to identify HPSA operating conditions which gave the highest increase in flotation performance. Variables were …

A Guide To Fifty Years Of Research At Montana Tech: Part 2 The Treatment Of Electroplating And Electromachining Metal Hydroxide Sludge For The Recovery Of Metal Values [See Also Part 1), Larry G. Twidwell

Metallurgy

ABSTRACT and FORWARD

The treatment and recovery of metal species from hydrometallurgical solutions and wastewater solids has been and continues to be an important research topic. This presentation includes a guide to the literature with a summary discussion of the research conducted at Montana Tech in the Department of Metallurgical and Materials Engineering during the 1984-2001 period. A previous presentation (Part 1) focused on the removal of arsenic, selenium, and other species by hydrometallurgical processes and the formation of environmentally stable disposable products. This guide is available at the reference presented above.

This following presentation (Part 2) is based on …

A Guide To Fifty Years Of Research At Montana Tech: Part 1-The Treatment Of Arsenic, Selenium, Thallium, Metal Bearing Solutions And Waste Solids, Larry G. Twidwell

Metallurgy

ABSTRACT and FORWARD

The removal of arsenic, selenium, and metal species from hydrometallurgical solutions and wastewaters has been and continues to be an important research topic. This presentation includes a discussion of the research conducted at Montana Tech in the Department of Metallurgical and Materials Engineering during the past fifty years. The discussion is focused on removal of arsenic by co-precipitation with Fe(III) and Fe(II), co-precipitation with Fe(III) and Al(III), reduction using elemental iron; the removal of selenium by elemental iron and catalysed iron; and the removal of cadmium, copper, nickel, zinc by co-precipitation with Fe(III) and Al(III).

This presentation …

Timeline - History Of The Metallurgy / Mineral Processing Programs (1900-2022), Jerome Downey, Larry G. Twidwell

Metallurgy

No abstract provided.

History Of The Metallurgy / Mineral Processing Programs (1900-2022), Jerome Downey, Larry G. Twidwell

Metallurgy

No abstract provided.

Treatment Of Arsenic-Bearing Minerals And Fixation Of Recovered Arsenic Products: An Updated Review, Larry G. Twidwell

Metallurgy

Mineral processing and extractive metallurgical operations have created and are creating appreciable arsenic bearing wastewater and waste solid products that have to be handled, treated for recycle, or treated for environmentally safe disposal. At present there are intense research and operational activities being conducted to provide the best viable processing procedures to ensure that the mineral processing and extractive metallurgical industries are profitable and environmentally secure. The focus of this presentation is on the element arsenic, even though many other deleterious elements may also be present in ores and concentrates. Numerous base metal resources contain arsenic bearing minerals, especially resources …

Investigation Of The Structure, Chemistry And Functional Performance Of Novel Biochars, Julie Elizabeth Muretta

Graduate Theses & Non-Theses

Biochars are a class of carbonaceous materials possessing high degrees of structural and chemical disorder in both organic and inorganic constituent phases. Despite this disorder, and in some cases because of this disorder, biochars have shown strong performance in adsorbing and even sequestering contaminants from soil, surface water and air. Biochar is the carbonaceous, solid product of heating carbonaceous feedstock in an oxygen-limited environment above 250°C, usually sourced from inexpensive, locally available agricultural and forestry wastes which can otherwise be difficult and expensive to dispose of. Biochar possesses attractive functional properties like high specific surface area, high micropore volume, and …

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 …

The Tempering Response Of Cpm® 3v Tool Steel Investigated Through Tensile Testing And Microstructural Observations, Stephen A.C. Hanson

Graduate Theses & Non-Theses

Heat treatment, tensile testing failure analysis, and microstructural evaluation of the Crucible Industries tool steel CPM® 3V was undertaken to investigate CPM® 3V’s tempering response for the following samples: As-Hardened (no tempering); tempered at 450°C, 550°C, 650°C, and 700°C; and As-Received (annealed). CPM® 3V tool steel is manufactured by Crucible Industries using their proprietary Crucible Particle Metallurgy (CPM®) technology. This material was heat-treated at four different tempering temperatures and was evaluated for tensile properties according to ASTM E8. A TMS landmark tensile fixture was used to establish the ultimate tensile strength and the yield strength of the material for the …

Fabrication And Characterization Of Manganese Oxide Surfaces From Polymer-Based Fiber Precursors, Molly C. Brockway

Graduate Theses & Non-Theses

Supercapacitors are an energy storage technologycombining properties of both capacitors and batteries to deliver high power and energydensities. Supercapacitors store charge through electrostatic and faradaic interactions between the electrode and ionic electrolyte. By improving the physical structure of electrodes, the interfacial area where energy storage occurs can be increased and electrochemical performance improved. New, fibrous, manganese oxide web-based structures tested for use as a supercapacitor electrode were fabricated by electrospinning and direct calcinationof metal salt-containing polymer fibers, and the effects of fabrication parameters on electrochemical performance were investigated. Data show that high polymer concentrations and low oxide precursor concentrations during …

Effect Of Global Energy Density On Dynamic Strain Hardening Of Selective Laser Melted Alsi10mg, Md Salah Uddin

Graduate Theses & Non-Theses

The characteristics of strain hardening of selective laser melting (SLM) processed AlSi10Mg under dynamic impact was investigated. The dynamic impact at high strain rate loading conditions occurs in many engineering applications, such as collisions of flying objects on aircraft engine components like bird impact, vehicle collisions, and impacts occur in sports events like club impact on golf balls and helmet impact. Among these various applications, the strength of the materials needs to characterize accurately for product quality, performance, and reliability.

AlSi10Mg is a lightweight metal alloy, and it has a growing demand in aircraft, military, and automotive applications. SLM is …

Particle Tracking Of A Simulated Melt Pool Of Selective Laser Melting, Prakash Gautam

Graduate Theses & Non-Theses

Metal additive manufacturing (AM) produces parts by addition as compared to subtraction of material. Selective laser melting (SLM) is an AM technique that prints objects layer-by-layer, selectively melting powders using a laser. The mechanical properties of SLM parts are affected by processing parameters and powder characteristics, both of which alter the molten melt pool flow field. Marangoni convection (M-flow) is a thermo-capillary mass transfer from a region of lower surface tension to a region of higher surface tension, referred to as a radially outward flow for SLM. However, in the presence of surface-active elements such as oxides and sulfides, the …

Synthesis Of Carbide Ceramics Via Reduction And Carburization Of Oxyanions Adsorbed Onto An Activated Carbon Matrix, Grant Wallace

Graduate Theses & Non-Theses

Carbide ceramics rank high among the hardest and most chemically resistant materials. Their ability to resist physical and chemical attack under conditions where more traditional materials fail make them very desirable for a number of industrial applications. Their use is limited, however, due to the expensive and energy-intensive methods required to produce them commercially.

A more versatile and energy-efficient process for commercial carbide production has been developed by synthesizing micron/sub-micron carbide ceramic particles through the adsorption and subsequent carburization of anions on an activated carbon matrix. Oxyanion solutions containing sodium tungstate, sodium molybdate, or sodium metasilicate are adsorbed onto activated …

A Novel Method For Making Titanium Dioxide For Photocatalytic Applications, Gary Wilson

Graduate Theses & Non-Theses

Titanium dioxide possesses near-ideal properties for large-scale application as a photocatalyst. It is cheap and abundant, nontoxic, and environmentally safe. However, it still suffers from logistical problems preventing its application in industry: namely, rapid electron-hole recombination and inability to utilize visible light. For nearly five decades researchers in this booming field have made numerous attempts to address these problems, doping and combining titanium dioxide with a wide range of materials. A novel ambient-temperature approach to synthesis and doping/modification of anatase-form titanium dioxide was attempted using both oxygen-rich and oxygen deprived synthetic routes. Reactants were exposed to various wavelengths of ultraviolet …

Effect Of Frother Strength And Solids On Gas Dispersion In A Cavitation Sparger Measured By Electrical Resistance Tomography, Philip Holdsworth

Graduate Theses & Non-Theses

Gas dispersion in column flotation is critical for optimizing particle-bubble interaction and maximizing recovery. The effect of various flotation frothers on axial gas dispersion rates in a column flotation cell were measured using electrical resistance tomography (ERT). Tests included two-phase (gas-liquid) and three-phase (gas-liquid-solid) to determine the effect of mechanical parameters and the presence of solids on gas dispersion. Gas holdup can be measured using ERT and utilized in the determination of axial gas dispersion rate in the column. The ERT is constructed with two sensor planes making it possible to simultaneously capture gas holdup values at one cm and …

Recovery Of Rare Earth Elements By Advanced Processing Technologies, Prince Sarfo

Graduate Theses & Non-Theses

Rare earth elements (REEs) are strategic materials of extreme importance to both military and civil applications. REEs are mined and processed because of their criticality. End of life rare earth metals are recycled for efficient use of natural resources and also to ensure supply of these critical raw materials. By using hydro- or pyro-metallurgi­cal approaches, REEs can be processed from mined ore or recycled from magnets and other materials as rare earth oxides, fluorides and chlorides. Typically, rare earth oxides are dissolved in a molten halide bath, converted to metal by electrolysis at elevated temperatures, and then recovered as a …

Microstuctural Analysis Of Additively Manufactured 308l Stainless Steel Produced By Plasma Arc Welding, Ryan Foley

Graduate Theses & Non-Theses

Additive Manufacturing (AM) is a technique to produce special products by depositing layers of material in a specific pattern. Wire and arc additive manufacturing (WAAM) is an AM technique that uses welding equipment that has been modified and automated to deposit layers of welding wire. Characterization of specimens produced by WAAM method is required to optimize the process parameters. This research focuses on the microstructure characterization of 308L stainless steel samples produced by a novel WAAM technique known as Plasma Arc Weld Print 3D (PP3D). PP3D consists of multiple plasma arc torches that can deposit material in two modes of …

Investigation Of Surface Treatment And Density Separation For Selective Recycling Of Plastics, Adilbek Baigabelov

Graduate Theses & Non-Theses

Froth flotation has been a useful method for flotation separation of plastics. Teeter bed concentration may also be potentially employed to accomplish gravity-based separation of plastics from a mixture. This work investigates selective separation of six different types of plastics using a novel method by combining advanced gravity concentration and froth flotation techniques. Surface active reagents were used during flotation studies for modification of surface properties of certain plastics in order to enhance selectivity. Elutriation technology in a teeter bed separator was successfully employed to achieve gravity-based concentration of certain plastics. The novel flowsheet was shown to recover plastics of …

Comparison Of Salicyl Hydroxamate Adsorption On Rare Earth Phosphates To Oxides And Carbonates, Stephanie Trant

Graduate Theses & Non-Theses

Adsorption behavior of the anionic collector salicyl hydroxamic acid (SHA) on a group of selected rare earth phosphates (REPs) was studied by means of experimental methods and modeling software. These REPs were then compared to rare earth carbonates (RECs) and rare earth oxides (REOs) to develop a trend. A suite of rare earth elements (REE) were studied that included light (LREE) and middle (MREE). Results for heavy (HREE) were inferred. Synthetic phosphate, oxide and carbonate powders of the rare earth elements Lanthanum (La), Cerium (Ce), Europium (Eu) and Dysprosium (Dy) were tested for these studies. Dysprosium phosphate was the only …

Surface Chemistry And Modelling Of Salicyl Hydroxamic Acid Adsorption At The Surface Of Rare Earth Oxides, Carbonates And Phosphates, Marc F. Sime

Graduate Theses & Non-Theses

The adsorption mechanism of salicyl hydroxamic acid (SHA, C7H7O3N) on rare earth minerals was investigated using two complementary methods: precipitation studies and modelling. Precipitation studies showed that SHA adsorption occurs through a displacement of the hydroxide ion at the surface in an ion exchange mechanism, leading to surface precipitation and/or chemisorption. Surface precipitation predominates in the light rare earth oxides (LREOs), while chemisorption predominates in the heavier REOs. Modelling revealed that adsorption of SHA on the REM surface is dependent upon the orientation of SHA on the surface as well as the distance between rare earth elements sites on the …

Material Properties Of Laser Powder Bed Fusion Processed 316l Stainless Steel, Steven Keckler

Graduate Theses & Non-Theses

Laser powder bed fusion additive manufactured 316L stainless steel specimens were evaluated to establish a baseline for future research in determining an optimized energy density and build orientation. Test specimens were printed at various energy densities. At each energy density, tensile and fatigue specimens were printed at 0o (longitudinal), 45o, and 90o (transverse) orientation to the build plate. Tensile and high cycle fatigue tests were performed then representative fracture surfaces were analyzed. The apparent melt track and dendrite size were evaluated using grain analysis software. Static loading of the tensile specimens showed a marginal difference in UTS for specimens with …

Novel Hybrid Perovskite Composites And Microstructures: Synthesis And Characterization, John P. Murphy

Graduate Theses & Non-Theses

The water-energy nexus has been described as one of the great problems of our time. In an ever-growing society the demand for resources such as water and electricity often dictate the magnitude and direction of growth of society. Efficient generation of electricity, with minimal socioeconomic pushback, is paramount in the stable growth of our society. Solar energy harvesting is a strong candidate for the efficient generation of electrical energy with increasingly minimal resource use in fabrication. As manufacturing processes improve and novel materials are discovered/optimized, solar energy harvesting becomes a more economically viable means of energy generation. Hybrid perovskites (HPs) …

Evaluation Of Metallurgical And Mechanical Properties Of Alsi10mg Produced By Selective Laser Melting, Luke J. Suttey

Graduate Theses & Non-Theses

Selective laser melting (SLM) additive manufacturing (AM) of metal powders has long been a focus in the study of AM due to the possibility of weight reduction, complex shape formation, and production cost savings. Although applicable to a variety of metals SLM AM of the AlSi10Mg alloy was studied in an attempt to characterize the effect of processing parameter and build angle variation on the final microstructural, fractographic, and mechanical properties of parts produced without any thermal post-processing techniques. Research was conducted on five build angles (0°, 30°, 45°, 60°, and 90°), and three Global Energy Densities (GED) (37.15, 45.39, …

Investigations Of Solid-State Sintering Behavior Of Binary Refractory Metal Oxide Systems, Maureen Chorney

Graduate Theses & Non-Theses

Refractory metals are commonly alloyed for improved corrosion resistance, thermal stability, and strength. In service, these alloys form highly stable oxides under mildly oxidizing conditions at relatively low temperatures. In order to recycle these materials, high temperature electrochemical processing is required to reduce the refractory metal oxides. To abet experimental evaluation of the electrochemical reduction process under development at the Idaho National Laboratory, binary mixtures of selected refractory metal oxide powders were sintered to produce cathode pellets, which could be suspended in the molten salt electrolyte during reduction experiments. Preparatory literature review revealed a paucity of published information relative to …

Characterization Of Process Induced Defects In Laser Powder Bed Fusion Processed Alsi10mg Alloy, Edward Stugelmayer

Graduate Theses & Non-Theses

Additive manufacturing using laser powder bed fusion (AM-LPBF) methods have recently experienced rapid growth and development, having the potential to replace manufacturing by plastic deformation, precision machining, or casting. AM offers advantages such as the freedom to design highly complex geometries, time and cost savings through material usage efficiency and shortened production cycles, and the potential for improved mechanical properties. Process induced defects, however, result in degradation and scattering of mechanical properties and hinder the widespread adoption of AM-LPBF in industry. This investigation focuses on the effects of varying energy density and build orientation on the evolution of process induced …

High Fidelity Kinetic Model For Flotation: Applications To Rare Earth Elements And Copper/Molybdenum Separations, Richard Ladouceur

Graduate Theses & Non-Theses

A high-fidelity kinetic model was developed to identify and elucidate the effects of varying principle froth flotation parameters on the sub-processes that occur within and between the flotation zones. Whereas traditional models fail to adequately address froth recovery and recovery by entrainment, the high-fidelity model defines these phenomena based on an improved understanding of the pulp/froth interface. Solution chemistry considerations that govern rare earth mineral separation by flotation were identified, characterized, and optimized. Application of novel surfactants such H205 and salicylhydroxamic acid (collectors) and dimethyl glycol monobutyl ether (depressant) was evaluated to define optimal flotation conditions. The effect of pressure …