Doctor of Philosophy, Case Western Reserve University, 2025, Physics

Chromatography approaches are ubiquitous in chemical separations, but their characterization, optimization, and scale-up rely on trial-and-error adjustments done at the ensemble level. Such empirical methods are costly in terms of energy, time, and money, while obscuring the molecular behavior that leads to the success or failure of a separation. In this work, we develop and apply experimental techniques to probe mass transport and adsorption kinetics of solid-liquid chromatography stationary-phase materials to inform separations design. Uniquely, we develop methods for 3D spatiotemporal analysis of commercial porous resins for chiral separations, as well as novel materials for rare earth element separations. We seek to deconvolve the contributions of transport and heterogeneous adsorption, while simultaneously informing and expanding kinetic models for predicting the performance and behavior of bulk-scale separations. We primarily rely on single-molecule fluorescence microscopy to probe nano-scale heterogeneities in adsorption and quantify the rare long-lasting adsorptions that complicate separations. Our in-situ imaging unveils the inaccessibility of the inner functionalized porous volume of industry-used resins, and then we show how to recover that access. By quantifying the effects that functionalization, solution environment and flow-through conditions have on nano-scale adsorptions, we demonstrate that experimentally informed single-molecule models can predict bulk-scale chromatographic separations. Through adsorption-desorption experiments, we further demonstrate and establish how first principles models can deconvolve the complex binding behavior of rare-earth-element binding proteins. We hope these studies inform the design and use of chromatography adsorbers and demonstrate how single-molecule methods and relatively simple models can provide a new avenue to characterize and direct separations design from the bottom-up.

Committee: Lydia Kisley (Advisor); Lydia Kisley (Committee Chair); Christine Duval (Committee Member); Giuseppe Strangi (Committee Member); Michael Hinczewski (Committee Member) Subjects: Analytical Chemistry; Experiments; Physics; Scientific Imaging

Master of Science (M.S.), University of Dayton, 2023, Chemistry

Rare earth elements are found in relative ubiquity within the earth's crust and have a multitude of application to both everyday life and military defense. On the periodic table, rare earth elements consist of all 15 lanthanides, along with scandium and yttrium. These elements have a wide variety of application, spanning from private and public sector applications, all the way to military defense, thus making them highly desirable metals for eventual utilization. Current methods of rare earth element extraction and purification involve environmentally harmful processes, leading to North America's decision to not mine for rare earth elements within its territories. This decision has created a distinct lack of self-sufficiency in rare earth element production, currently resulting in a complete reliance of rare earth element imports from other countries, namely China. Due to the current processes of rare earth element extraction and purification posing large detriment to environmental stability along with a decrease in U.S. autonomy, determination of new, safer routes of rare earth element processing is of utmost priority. Specific proteins are known to bind metal ions, which has provided the scientific foundation for a protein-based extraction and purification method targeting rare earth elements. Previous research has identified a protein which is known to bind lanthanides, providing a high potential prospect for the solution to this problem. The protein of interest, named lanmodulin (LanM), contains four regions, denoted as EF hands, with three of which being involved in lanthanide binding. Building upon the previously mentioned solution is a thioredoxin protein found in the extremophile Pyrococcus furiosus. P. furiosus thioredoxin has shown the ability to stably accept newly introduced peptide sequences within its native amino acid sequence. The area of insertion possesses closely located cysteine residues which show p (open full item for complete abstract)

Committee: Kevin Hinkle (Committee Chair); Rajiv Berry (Committee Chair); Justin Biffinger (Committee Chair) Subjects: Chemical Engineering; Chemistry; Computer Science; Molecular Chemistry; Molecular Physics; Molecules

Doctor of Philosophy, The Ohio State University, 2023, Civil Engineering

Reducing CO2 emissions will be critical for meeting global targets of net zero CO2 emissions by the year 2050 and net negative CO2 emissions by 2100. To help meet these emission reduction targets there will need to be a rapid transition from a historical reliance on fossil fuels for energy generation to renewable and low CO2 emission energy generation technologies, a so-called energy transition. The energy transition will feature an increase in demand for valuable resources like rare earth elements and see widespread deployment of carbon capture, utilization, and storage infrastructure. In the first chapter we explore a novel trap-extract-precipitate (TEP) system that looks to trap rare earth elements (REEs) found in coal mine drainage before later extracting the REEs from the trap material. We apply a techno-economic analysis and life cycle assessment to two different iterations of the TEP system design to determine a levelized cost of the process and associated environmental and human health impacts. Our results indicate that the levelized cost of the process is $278/gT-REE and $86/gT-REE for two designs using different industrial by-products. Further, when considering just the passive treatment cell of the system design, we observe environmental and human health benefits that are lost once we shift the scope to include the chemical extraction of REEs. Chapter 3 evaluates the impact of stacked storage on carbon capture and storage (CCS) systems by looking at how networks change when CO2 is emplaced in different geologic CO2 storage (GCS) locations. This case study focuses on Oklahoma, which has GCS resources and existing CO2-EOR operations, both needed for stacked storage. We use an economic engineering geospatial linear optimization model, SimCCSPRO, to determine the least cost combination of point sources, GCS locations, and pipeline networks. Our results suggest point sources of CO2 drive CCS pipeline network deployment. Additionally, we identify counties t (open full item for complete abstract)

Committee: Jeffrey Bielicki (Advisor); Daniel Gingerich (Committee Member); Gil Bohrer (Committee Member); Jordan Clark (Committee Member) Subjects: Civil Engineering; Environmental Engineering

Master of Science, The Ohio State University, 2022, Civil Engineering

Acid mine drainage (AMD) and the associated mine land sediments are a valuable source of rare earth elements (REEs) and critical minerals with concentrations of REEs in AMD often orders of magnitude higher than those in river water and seawater. Recovering REEs while cleaning up AMD provides the potential to offset the cost of reclamation. In this study, we are evaluating the REE content and distribution in the sediments associated with two AMD locations in SE Ohio that exhibit high REE content. The study sites, ‘Flint Run' and ‘Howard-Williams Lake', are complex sites with multiple past remediations and reclamation attempts that continue to produce AMD with REE concentrations up to 0.9 mg/L and 1.9 mg/L, respectively. Soil cores were collected from the two sites using an auger and split-spoon sampler. Samples were collected at approximately five-foot increments and trace element and REE concentrations were analyzed on digested samples using inductively coupled plasma atomic emission spectroscopy. The mineralogy of the sediments was analyzed with a high-resolution X-Ray diffractometer. Our results show the layers of fill used to reclaim the sites were not uniform spatially or with depth and were comprised of a mixture of silty clay, underclay, coal refuse, shale, and sandstone. Samples identified as being associated with coal (i.e., clay with coal fines and coal refuse), regardless of the depth measured, had higher REE concentrations (up to 437.9 ppm total REE) in comparison to the other compositional layers studies (~36 ppm total REE). Samples associated with coal had concentrations ranging from 4.2-126 ppm for Ce to 4.5-52.6 ppm for Nd. These layers also exhibited elevated concentrations of Fe and Al. At water pH values of 5.1-6.6, REEs were expected to precipitate with Fe and Al minerals into the sediment, which was consistent with the pH value of water collected during sample collection at Howard-Williams Lake. Statistical analysis and XRD results indicate that (open full item for complete abstract)

Committee: John Lenhart (Advisor); Chin-Min Cheng (Committee Member); Tarunjit Butalia (Committee Member); Allison MacKay (Committee Member) Subjects: Civil Engineering; Environmental Engineering; Geological

MS, University of Cincinnati, 2018, Arts and Sciences: Geology

In this study, the question of microenvironmental change related to the overall eruption pattern from the Siberian Traps was examined. Using the unique rare earth element geochemistry that was produced from the successive eruptions, a geological trace that links the Siberian Traps to the environmental collapse from the effects of windblown ash was found in using over 400 marine sediment samples taken from 7 different Permian-Triassic Boundary sections. The following results show values likely indicative of material derived from the lower crust, upper mantle with the Eu/Eu* anomalies from Zal, a microcontinent in the Tethys Ocean, Gujo-Hachiman, an open ocean site in the eastern Panthalassic Ocean, along with Guryul Ravine and Spiti on the northwestern margin of Gondwana. These results represent a global signal, and could reflect a deleterious effect upon marine and terrestrial ecosystems from the possible volcanic ashfall that was produced from the Siberian Traps.

Committee: Thomas Algeo Ph.D. (Committee Chair); Warren Huff Ph.D. (Committee Member); J Barry Maynard Ph.D. (Committee Member) Subjects: Geology

Master of Science, Miami University, 2015, Computational Science and Engineering

Fluorite is a common mineral in the earth. Rare Earth Elements (REEs) readily incorporate into fluorite during its growth and are found to be sectorally zoned (i.e., having substitutional concentration differences among the nonequivalent sectors). The underlying causes of sectoral zoning (SZ) of REEs in fluorite are not clear. Also, the mechanisms which differentiate REEs in terms of binding at kinks (i.e., intermediate twists in crystal growth steps) at a crystal surface are still unknown. To study SZ, it is important to explore the dynamics of crystal growth during the adsorption of REEs. In this work, studies have been done to find the internal reasons behind the SZ by simulations and computations at both the atomic and sub-atomic levels using electronic structure methods. Atom Clusters have been modeled which represent the fluorite surface including various REEs at kink sites and nonequivalent faces. Simulation results of electronic structure methods provides detailed explanations to understand the sectoral zoning by exploring the surface structure, energetics and internal morphology for REE adsorption at the kink site of fluorite. Results indicate that adsorption energy differences among faces and differing bond orders among REEs are likely to be principle causes of SZ at the adsorption stage.

Committee: James Moller Dr. (Advisor); John Rakovan Dr. (Committee Member); Fazeel Khan Dr. (Committee Member) Subjects: Chemistry; Computer Science; Mechanical Engineering

PhD, University of Cincinnati, 2009, Engineering : Materials Science

In the framework of crystal field theory, the absorption spectra in the Vis (blue)-UV region of trivalent uranium ion doped into LaCl3 and CeCl3 single crystals are directly predicted and simulated. A new computational method for modeling the orbital hybridization (mixing of electron configurations of opposite parities) is developed with a modified crystal field approach. The developed method is based on the complete diagonalization of the modified crystal field Hamiltonian (which includes both even and odd terms of the crystal field) defined in the basis set spanned by all 5f3 and 5f26d wave functions (1274 states in total) for the open shell electrons of U3+ ion. The method provides a fundamental understanding and quantitative analysis of the crystal-field induced 5f-6d mixing in U3+:LaCl3 and U3+:CeCl3 (C3h site symmetry at the U3+ position). The odd terms of the crystal field interaction (B33(f-d) and B53((f-d) in the C3h symmetry) selectively couple the states of the 5f3 and 5f26d configurations, producing a shift of the energy levels and allow electric dipole transitions between the configuration-mixed states. The mixture of the 5f and 6d configurations was described by introducing an index of configuration mixing, which varies from 0 (no mixing) to 1.0 (maximum mixing of electron configurations). For the first time, the exchange charge model (ECM) of crystal field theory has been used to calculate the parameters of crystal field acting on the 5f and 6d electrons of U3+. The calculated crystal field parameter values based on ECM are further optimized along with free-ion parameters of the Hamiltonian in non-linear least squares fitting of the calculated U3+ energy levels to the experimental absorption spectra. The eigenfunctions of the U3+ energy levels (with configuration mixing) can be directly used to calculate the electric dipole transition intensities and simulate the absorption spectra in the spectral region where 5f3 and 5f26d configurations overlap. Int (open full item for complete abstract)

Committee: Donglu Shi PhD (Committee Chair); Dale Schaefer PhD (Committee Member); Relva Buchanan ScD (Committee Member); Dong Qian PhD (Committee Member) Subjects: Condensation; Materials Science; Molecules

MS, University of Cincinnati, 2003, Arts and Sciences : Geology

Studies of volcanic rocks from Hawaii reveal that the islands were formed through four distinct stages of volcanism. The origin of alkalic rocks produced during the last stage of development is not completely understood. Alkalic basalts can be generated at both high and low pressures. A new method of constraining pressure-temperature conditions of formation was developed, using the compositions of alkalic rocks from Haleakala Volcano. Initial P-T calculations indicated that the rocks formed from low degrees of melting over a range of pressures in the mantle (polybaric melting). Using a trace element modal melting equation and highly incompatible element concentrations, the degree of melting required to produce the Haleakala alkalic magmas was estimated. The results of these calculations indicate that low degrees of melting in the spinel peridotite zone of the mantle under polybaric conditions was required to produce the Haleakala alkalic basalts.

Committee: Dr. Attila Kilinc (Advisor) Subjects: Geology