Chemical Engineering Commons^™

Instructional Slides From Molten Salt Electrochemistry Symposium (Moses) 2026, Devin Rappleye, Carlos Mejia, Alex Peroff

Faculty Publications

This instructional slide set was developed for the 2026 Molten Salt Electrochemistry Symposium (MoSES) as an introduction and review of fundamental electrochemical concepts and methods used in molten salt systems. The material is intended for students, researchers, and practitioners seeking to better understand and interpret electrochemical measurements in high-temperature molten salts.

Topics include electrochemical thermodynamics, kinetics, mass transfer, electrode potentials, cyclic voltammetry, chronopotentiometry, chronoamperometry, square-wave voltammetry, electrochemical impedance spectroscopy (EIS), and common approaches for analyzing electrochemical data. Emphasis is placed on building physical intuition, understanding underlying assumptions, recognizing common experimental artifacts, and connecting electrochemical signals to real chemical and transport …

The Open Wiki Of Electrochemical Methods (Owem): A Community-Driven Educational Resource, Anderson Fuller, Devin Rappleye

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The traditional resources for learning electrochemical methods—textbooks, academic literature, and university coursework—remain essential but are limited in accessibility, update frequency, and practical usability. This paper introduces the Open Wiki of Electrochemical Methods (OWEM), an open-access, community-driven platform designed to complement these resources. OWEM organizes content into equations, definitions, methods, tutorials, and supplementary articles, with a heavy emphasis on experimental relevance. A case study on cyclic voltammetry demonstrates how OWEM consolidates foundational theory, lesser-known results, and practical guidance within a continuously maintainable framework to benefit the broader electrochemistry community.

A Comparative Study Of Tin Electrorefining In Molten Licl–Kcl–Cacl₂: Experimental Two-Electrode Current Control And Theoretical Three-Electrode Potential Control, Bryant Johnson, George Ankrah, Ander Fuller, Devin Rappleye

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Molten salt electrorefining is a mature technology for metal recovery, yet conventional current‑controlled, two‑electrode operation provides limited electrochemical selectivity and restricted insight into electrode‑specific behavior. In this work, a simplified model is developed to compare current‑controlled two‑electrode electrorefining data with a potential‑controlled three‑electrode electrorefining simulation using tin in molten LiCl–KCl–CaCl₂ as a surrogate for plutonium processing. The model examines anodic and cathodic limitations under fixed‑potential operation and evaluates implications for selectivity, efficiency, and runtime relative to experimentally demonstrated two‑electrode performance. Results indicate that independent potential control enables operation closer to thermodynamic selectivity limits, with the potential to suppress impurity oxidation …

Evaluation Of Quantification Methods Applied To Overlapping Ftir Features, Benjamin P. Diehl

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Quantifying overlapping FTIR spectral features is critical for electrochemical analysis but often requires complex deconvolution. This work systematically evaluates several area ratio and proxy-based quantification methods using a controlled synthetic spectral model with varying signal-to-noise ratio, peak spacing, width, background, and data resolution. Constrained peak fitting and fixed-window integration consistently exhibit near-perfect monotonicity (Spearman ≈ 1.000) and linearity (Pearson ≈ 0.999–1.000) across all conditions. In contrast, derivative and moment-based metrics show sensitivity to peak overlap, width, and background. These results demonstrate that physically grounded area-based methods provide the most robust and reliable quantification of overlapping FTIR features.

Modified Anodic Stripping Voltammetry For In Situ Analysis Of Liquid Metal Composition In Molten Salt Electrorefining Systems, James H. Manner

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The development of in-situ analytical techniques for high-temperature molten salt systems is critical for advancing electrorefining in nuclear fuel recycling and metallurgical purification. This study proposes Modified Anodic Stripping Voltammetry (MASV), using a “dip-and-strip” approach where a tungsten electrode captures molten Sn–Ni alloy before stripping in LiCl–KCl–CaCl₂ at 415 °C. OCP results showed rapid loss of the metal layer due to poor wetting, and stripping peaks gave compositions inconsistent with the alloy, likely reflecting Sn/Sn²⁺ and Sn²⁺/Sn⁴⁺ redox processes. These results highlight interfacial limitations and the need for improved electrode materials and surface modification.

Data For "Unified Vapor Pressure Correlations For Lanthanide And Actinide Chlorides: An In-Depth Statistical And Thermodynamic Approach", J. Marvin Torrie, Nicolas Marvin Christensen, Kyle Duke, Carlos Mejia, Larry Baxter, Devin Rappleye

ScholarsArchive Data

This submission contains machine readable data (.csv) for all data from the publication "Unified Vapor Pressure Correlations for Lanthanide and Actinide Chlorides: An In-depth Statistical and Thermodynamic Approach". It contains the data contained in all figures in the paper and its supplementary material except for the water vapor pressure data in Figures 1 and 2. In addition, this submission contains all the original vapor pressure measurements (241 sets) from the sources reviewed in the paper.  Sufficient information is provided that readers can identify the original sources of these data sets if needed.

Distributed Model Predictive Control-Based Power Management Scheme For Grid-Integrated Microgrids, Sergio Escareno, Sijo Augustine, Liang Sun, Sathishkumar J. Ranade, Olga Lavrava, Enrico Pontelli, John Hedengren

Faculty Publications

Transitioning from traditional electrical grids to smart grids is currently an ongoing process that many nations are striving for due to their access to renewable resources. Energy management is one of the key parameters that decides the performance of such complex systems. Distributed Model Predictive Control (DMPC) is a promising technique that can be used to improve the energy management of grid-connected systems. This paper analyzes a grid-connected inverter system with DMPC that exchanges key operating parameters with the grid to optimize coordinated power sharing between its respective loads. The state-space model for the inverter is derived and verified to …

Molecular Survival Strategies Against Kidney Filtration: Implications For Therapeutic Protein Engineering, William Heaps, Anna Elise Packard, Kristina M. Mccammon, Tyler P. Green, Joseph P. Talley, Bradley C. Bundy, Dennis Della Corte

Faculty Publications

The glomerular filtration barrier poses a significant challenge for circulating proteins, with molecules below ~60–70 kDa facing rapid renal clearance. Endogenous proteins have evolved sophisticated evasion mechanisms including oligomerization, carrier binding, electrostatic repulsion, and FcRn-mediated recycling. Understanding these natural strategies provides blueprints for engineering therapeutic proteins with improved pharmacokinetics. This review examines how endogenous proteins resist filtration, evaluates their application in protein engineering, and discusses clinical translation including established technologies (PEGylation, Fc-fusion) and emerging strategies (albumin-binding domains, glycoengineering). We address critical challenges of balancing half-life extension with tissue penetration, biological activity, and immunogenicity—essential considerations for the rational design of next-generation …

Precision Acoustofluidics For High-Throughput Mechanobiology In Suspension Cells, Kaichun Yang, Ruoyu Zhong, Ke Li, John Mai, Pengzhan Liu, Ye He, Joseph Rich, Ying Chen, Janna Wang, Zhiteng Ma, Zhiteng Ma, Xianchen Xu, Qian Wu, Tony Jun Huang

Faculty Publications

Mechanomodulation, the process of altering cellular behavior through applied mechanical forces, plays a critical role in physiological processes and has substantial implications for cancer therapy, immunology, and drug development. However, precise and efficient stimulation of nonadherent cells remains a major challenge, limiting the investigation of mechanotransduction pathways and the development of targeted therapeutics. Here, we developed an acoustofluidic platform named Suspension-cell Targeted Response to Excitation via Acoustofluidic Mechanomodulation (STREAM) to enable precise, high-throughput stimulation of suspension cells. STREAM accomplishes this using 101.14-megahertz high-frequency surface acoustic waves to deliver controlled mechanical stimulation at a throughput of 500,000 cells per minute. STREAM …

The Composition Of Gases From A Diffusion Flame Above Longleaf Pine Needle Fuel Beds, David R. Weise, Thomas H. Fletcher, Timothy J. Johnson, Weimin Hao, Russell G. Tonkyn, Catherine A. Banach, Javier Palarea-Albaladejo, Mahsa Alizadeh, Stephen Baker

Faculty Publications

The gas and tar composition of a wildland fire diffusion flame from longleaf pine needles is currently relatively unmeasured and more data are needed to fill in the gap between pyrolysis data and smoke plume data, thus improving physical and chemical modeling of wildland smoke formation. A pilot experiment to measure light gas and tar composition of such a flame is described for three flame zones: persistent flame (flame base), intermittent flame, and smoke plume. Flame gases from 24 experimental fires were collected in canisters and analyzed for CO2, CO, H2, CH4, and C2 to C7 hydrocarbon gases. Other light …

Effect Of Inter Electrode Distance On Electrochemical Mineralization Of Calcium Carbonate In Mildly Acidic Environments, Irene Walker, Ivy Wu, Steven Decaluwe, Robert Bell, Kerry Rippy

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The effect of inter electrode distance (IED) on electrochemical mineralization in a parallel plate cell with a stainless-steel working electrode is presented. Three IEDs were tested, 6.5 mm, 15.5 mm, and 22.0 mm, for their water reduction effectiveness to create a region of local alkalinity that stimulates calcium carbonate precipitation in mildly acidic conditions. Chronoamperometry at -1.6 V for 30 minutes with ex-situ optical microscopy and scanning electron microscopy (SEM) were used. At the smallest IEDs, crystal clusters formed in growth-favored regimes as compared to the largest IED, where nucleation dominated, leading to encasement of the SS mesh. Rapid precipitation …

Optimal Sizing Of Battery Energy Storage Systems For Peak Shaving And Demand Response Using A Degradation-Aware Bayesian Optimization-Mixed-Integer Linear Programming Framework, Jiwei Yao, Blake Billings, Tao Gao, John Hedengren, Kody M. Powell

Faculty Publications

The increasing integration of renewable energy and rising electricity demand highlight the importance of battery energy storage systems for peak shaving and demand response. Unlike prior approaches that overlook operational impacts on degradation, this study proposes a Bayesian Optimization–Mixed Integer Linear Programming framework for optimal battery energy storage system sizing. In this framework, Mixed Integer Linear Programming determines short-term scheduling while a calibrated electrochemical model iteratively evaluates degradation. The central hypothesis is that the framework can efficiently identify optimal sizes that yield realistic and economically robust outcomes. The method is tested across three scenarios: peak shaving, peak shaving with energy-reduction …

Programmable Acoustofluidic Engineering For Creating Gradient Biomaterials, Jujing Lu, Ye He, Jianping Xia, Mingyuan Liu, Joseph Rich, Ke Jin, Ruoyu Zhong, Kaichun Yang, Jiao Qian, Ying Chen, Ke Li, Zhiteng Ma, Tony Jun Huang

Faculty Publications

Gradient biomaterials that exhibit spatially varying physical, chemical, or biological properties can be used in various applications such as tissue engineering, organoid development, mechanobiology, and spatially controlled drug delivery. However, current fabrication methods often suffer from limited gradient precision, restricted material compatibility, and poor reproducibility. Here, we introduced gradient regulation via acoustofluidic dynamic engineering (GRADE), a programmable system to generate high-fidelity gradient biomaterials across different material systems. By incorporating focused interdigital transducers with the pulsed surface acoustic wave actuation, GRADE can achieve tunable and directional acoustic streaming (0 to 22 millimeters per second), which allows accurate regulation of the gradient …

Fabrication And Evaluation Of Large Alumina Crucibles By Vat Photopolymerization Additive Manufacturing For High-Temperature Actinide Chemistry, R. Joey Griffiths, Christy Santoyo, Jean-Baptise Forien, Bradley Childs, Andrew J. Swift, Andrew Cho, Alexander Wilson-Heid, George Ankrah, Devin Rappleye, Aiden A. Martin, Jason Jeffries, Kiel Holliday

Faculty Publications

Additive manufacturing (AM) offers opportunities to advance the design and function of ceramic tooling in high temperature actinide pyrochemistry. In technical ceramics such as alumina, conventional forming techniques often restrict design flexibility and can limit experimental progress. In this study, we investigate the use of vat photopolymerization (VP) with commercial resins to fabricate large-scale alumina crucibles, reaching dimensions up to 125 mm, which is significantly larger than typically reported for dense VP ceramics. Notably, these additively manufactured components are produced using consumer-grade hardware, which limits process control, but offers significant upside in scalability and accessibility. Using microscopy and X-ray computed …

Polydopamine-Coated Magnetic Nanoparticles Data, William G. Pitt

ScholarsArchive Data

This data archive contains raw data and processed data related to research and development of magnetic nanoparticles that adhere to bacteria. This data is the foundation of data in the MS thesis of Bowen Houser, and publications and presentations related to that research effort. Polydopamine-coated magnetic nanoparticles are found to be very adhesive to gram-positive bacteria, and less adhesive to gram-negative bacteria. These data files contain information for S. aureus, S. epidermidis, S. mutans, E. coli, P. aeruginosa, and N. perflava. Some data include the kinetics of capture.

Data Release Of 5-Fluorouracil From Polylactic Acid Microparticles Containing Magnetic Nanoparticles, William G. Pitt

ScholarsArchive Data

This data archive contains raw data and processed data related to research and development of the release of the chemotherapy drug 5-fluororacil from microparticles of poly(lactic acid) which also contain superparamagnetic magnetite nanoparticles. This data is the foundation of data in the MS thesis of Tyler Green, and publications and presentations related to that research effort.

Pyrolysis Of Foliage From 24 U.S. Plant Species With Recommendations For Physics-Basedwildland Fire Models, Mahsa Alizadeh, Thomas H. Fletcher

Faculty Publications

Pyrolysis of 24 samples of foliage from three U.S. regions with frequent wildland fires (Southeastern U.S., northern Utah and Southern California) was studied in a fuel-rich flat-flame burner system at 765 ◦C (for Southeastern U.S. samples) and 725 ◦C (for northern Utah and Southern California species), with a heating rate of approximately 180 ◦C/s. These conditions were selected to mimic the conditions of wildland fires. Individual plant samples were introduced to the high temperature zone in a flat-flame burner and pyrolysis products were collected. Tar was extracted and later analyzed by GC/MS. Light gases were collected and analyzed by GC/TCD. …

Evaluating Platinum, Gold, Glassy Carbon, And Graphite Anodes For Chlorine Evolution In Molten Calcium Chloride Salt, Cameron Vann, Shelssie Klvacek, Carlos Mejia, Devin Rappleye

Faculty Publications

The chlorine evolution reaction (CER) in molten CaCl₂ plays a critical role in high-temperature electrochemical processes, including chlorination, metal refining, and used nuclear fuel treatment. This study evaluates the performance of gold (Au), platinum (Pt), glassy carbon (GC), and graphite anodes for the CER under consistent electrochemical conditions. Anode performance was assessed based on chlorine (Cl₂) gas evolution, material robustness, and kinetic parameters. Cl₂ generation was directly confirmed using quadrupole mass spectrometry for Pt, GC, and graphite anodes. GC and graphite demonstrated stable and sustained CER activity. Pt and Au were shown to have significant mass …

Using Serial Open Circuit Potentiometry To Study Ce And Gd Deposition In Molten Licl-Kcl Eutectic, Ranon G. Fuller, Guy L. Fredrickson, Devin Rappleye

Faculty Publications

The ability to electrochemically separate individual species in a pyrochemical reprocessing salt relies on first being able to detect a separation in their reaction potentials. This requires the ability to measure reaction potentials with extreme precision. In this work, we introduce a novel technique called serial open circuit potentiometry (SOCP) and demonstrate its effectiveness at precisely measuring metal deposition reaction potentials. SOCP has several advantages over traditional open circuit potentiometry, including its abilities to quantify the error of measured equilibrium potentials by averaging many individual OCP measurements, determine overpotential deposition nucleation potentials to instrument precision, and simultaneously determine the nucleation …

A C++ Library For Turbulent Mixing Simulation Using Hierarchical Parcel Swapping (Hips), Masoomeh Behrang, Tommy Starick, Heiko Schmidt, David O. Lignell

Faculty Publications

Turbulence models are crucial for simulating flows at all scales, capturing both large-scale structures and small-scale mixing. Software libraries that implement such models should support modular integration, customization, and scalability across different simulation frameworks. This paper presents Hierarchical Parcel Swapping (HiPS), a C++ library documented with Doxygen and available on GitHub. HiPS supports both mixing and reactions and can be used as a standalone model or as a subgrid model in CFD simulations. The code includes examples for users to run it as a standalone model. Additionally, considerations for using it as a subgrid model are provided.

Magnetic Nanoparticles Tethered With Zn–Dpa For The Removal Of Bacteria From Red Blood Cell Suspension, Tochukwu P. Okonkwo, Rajendra P. Gautam, Jacob B. Limburg, Breckin L. Forstrom, Bowen J. Houser, Aaron Rappleyea, Tyler P. Green, Joseph P. Talley, Alexander D. Daum, Stacey J. Smith, Karine Chesnel, William G. Pitt, Roger G. Harrison

Faculty Publications

Bacterial infections continue to drive the need for more effective and rapid methods for bacterial analysis. To address this, magnetic nanoparticles (MNPs) have emerged as promising tools, especially when their surfaces are modified with bacteria binders. The bis-zinc–dipicolylamine (Zn–DPA) complex is known for its broad affinity to bacteria. We have synthesized MNPs via a thermal decomposition method, encapsulated them in silica, modified their surface with Zn–DPA, and tested their ability to remove bacteria. The MNPs retain their superparamagnetic properties and crystallite structure after being encapsulated. The MNPs coated with silica and Zn–DPA effectively bind and remove both Gram-positive and Gram-negative …

Effect Of Short-Chain Polymer Binders On The Mechanical And Electrochemical Performance Of Silicon Anodes, Fei Sun, L. Zurita-Garcia, Dean R. Wheeler

Faculty Publications

Polymer binders are crucial components in providing both mechanical support and chemical stability to the structure of porous Li-ion electrodes. Particularly in silicon anodes, the active material undergoes substantial volume expansion of up to 275%. Due to the mechanical constraint of the current collector, these silicon materials tend to expand in the normal direction while exhibiting substantial particle rearrangement and plastic deformation. Conventional rigid binders such as polyacrylic acid (PAA) and polyimide (PI), while providing satisfactory initial capacity, do not eliminate diminished long-term performance. Our research attempts to develop binder formulations that can accommodate sufficient flexibility for the substantial volume …

Investigation Of A Stable And Saturated Reference Electrode Using Metal Chlorides And Oxides In Eutectic Licl-Kcl Molten Salts, Carlos Mejia, Devin Rappleye

Faculty Publications

Stable and reproducible reference electrodes (REs) are essential for electrochemical systems operating in high-temperature molten salts, where consistent control of potential is required. This study uses three different solutes to investigate the development and evaluation of REs in eutectic LiCl-KCl at 773 K. The solutes tested were NiCl₂, AgCl, and NiO, each prepared at multiple concentrations to assess stability, reproducibility, and saturation. Electrochemical stability was measured over three days using chronopotentiometry (CP), followed by open circuit potential (OCP), with cyclic voltammetry (CV) also integrated to monitor changes in electrochemical behavior over time. The CP-OCP approach established a Li …

Investigation Of A Stable And Saturated Reference Electrode Using Metal Chlorides And Oxides In Eutectic Licl-Kcl Molten Salts, Carlos Mejia, Devin Rappleye

Faculty Publications

Stable and reproducible reference electrodes (REs) are essential for electrochemical systems operating in high-temperature molten salts, where consistent control of potential is required. This study uses three different solutes to investigate the development and evaluation of REs in eutectic LiCl-KCl at 773 K. The solutes tested were NiCl2, AgCl, and NiO, each prepared at multiple concentrations to assess stability, reproducibility, and saturation. Electrochemical stability was measured over three days using chronopotentiometry (CP), followed by open circuit potential (OCP), with cyclic voltammetry (CV) also integrated to monitor changes in electrochemical behavior over time. The CP-OCP approach established a Li+/Li redox potential, …

Recent Advances In Developing Cell-Free Protein Synthesis Biosensors For Medical Diagnostics And Environmental Monitoring, Tyler P. Green, Joseph P. Talley, Bradley Charles Bundy

Faculty Publications

Cell-free biosensors harness the selectivity of cellular machinery without living cells’ constraints, offering advantages in environmental monitoring, medical diagnostics, and biotechnological applications. This review examines recent advances in cell-free biosensor development, highlighting their ability to detect diverse analytes including heavy metals, organic pollutants, pathogens, and clinical biomarkers with high sensitivity and specificity. We analyze technological innovations in cell-free protein synthesis optimization, preservation strategies, and field deployment methods that have enhanced sensitivity, and practical applicability. The integration of synthetic biology approaches has enabled complex signal processing, multiplexed detection, and novel sensor designs including riboswitches, split reporter systems, and metabolic sensing modules. …

Collection Of Instructional Slides From Molten Salt Electrochemistry Symposium (Moses), Devin Rappleye, Carlos Mejia

Faculty Publications

During the Molten Salt Electrochemistry Symposium (MoSES) on July 30-31, 2025, interactive instruction was given to the attendees including live demonstrations. These slides contain the introductory instructions given for each learning module at MoSES 2025. Please visit https://pyro.byu.edu/moses for more information.

An Acoustofluidic Device For Sample Preparation And Detection Of Small Extracellular Vesicles, Jessica F. Liu, Jianping Xia, Joseph Rich, Shuaiguo Zhao, Kaichun Yang, Brandon Lu, Ying Chen, Tiffany Wen Ye, Tony Jun Huang

Faculty Publications

Small extracellular vesicles (sEVs) have emerged as powerful vectors for liquid biopsy, offering a noninvasive window into the dynamic physiological and pathological states of the body. However, to fully leverage the clinical potential of sEV biomarkers, it is imperative to develop robust and efficient technologies for their isolation and analysis. In this study, we introduce a novel sharp-edge acoustofluidic platform designed for rapid and effective sample preparation, coupled with sensitive detection of specific sEV populations based on their surface markers. Our approach utilizes acoustically activated sharp-edge microstructures to concentrate bead-bound sEVs within the microfluidic device, facilitating immediate visualization by fluorescence …

Cell-Free Protein Synthesis Reactor Formats: A Brief History And Analysis, Dallin M. Chipman, Anna C. Woolley, Davu N. Chau, William A. Lance, Joseph P. Talley, Tyler P. Green, Benjamin C. Robbins, Bradley Charles Bundy

Faculty Publications

Cell-free protein synthesis (CFPS) has transformed protein production capabilities by eliminating cellular constraints, enabling the rapid expression of difficult-to-produce proteins in an open, customizable environment. As CFPS applications expand from fundamental research to industrial production, therapeutic manufacturing, and point-of-care diagnostics, the diverse array of reactor formats has become increasingly important yet challenging to navigate. This review examines the evolution and characteristics of thirteen major CFPS reactor formats, from traditional batch systems to advanced platforms. The historical development of CFPS reactors from the 1960s to present day is presented. Additionally, for each format, operational principles, advantages, limitations, and notable applications are …

Eliminating Assay Background Of A Low-Cost, Colorimetric Glutamine Biosensor By Engineering An Alternative Formulation Of Cell-Free Protein Synthesis, Joseph P. Talley, Tyler J. Free, Tyler P. Green, Dallin M. Chipman, Bradley Charles Bundy

Faculty Publications

Glutamine is an essential biomolecule that plays a pivotal role in many diseases, such as cancer, where it can serve as fuel for rapid proliferation. Treatments for these diseases can be monitored and optimized through the detection of glutamine, though standard glutamine detection procedures are costly and require complex instrumentation. Cell-free protein synthesis (CFPS) has recently enabled a paper-based, colorimetric glutamine sensor that carries the potential to increase test accessibility while dramatically reducing consumer cost to enable at-home, rapid treatment monitoring. Test sensitivity remained limited by residual assay background, thus motivating this work where CFPS reactions traditionally formulated with glutamate …

Small-Scale Production Of Bespoke Accelerated Aging Plutonium Alloy, K. S. Holliday, A. M. Parkes, Devin Rappleye, D. J. Roberts, K. J. Kondrat, S. A. Simpson, A. J. Swift, U. Mehta, R. M. Kissinger, D. L. Rosas, L. S. Ripplinger, E. R. Tardiff, S. L. Harris, S. Perkins, C. Hawkins, N. J. Gibbs, R. J. P. Driscoll, A. T. Sidambe, R. A. Cole, T. T. Roehling, J R. Jeffries

Faculty Publications

This study demonstrates the 100 g scale manufacture of a plutonium alloy that ages at an accelerated rate. The resulting alloy ages six times faster than typical weapons-grade plutonium due to the addition of ²³⁸Pu. As a major innovation, the process involved using a partial direct oxide reduction technique. This method was achieved by developing a new, complex geometry stirrer using additive manufacturing to reduce the ²³⁸Pu oxide and efficiently incorporate it into weapons-grade plutonium metal. The material was then purified by molten salt extraction and electrorefining before being alloyed with gallium. The alloy was then cold-rolled and …