Samantha A. Labb

About

I am currently a fourth year PhD Candidate at Colorado State University studying radiochemistry and radiation health physics. My journey started at Salisbury University where I completed my BSc. in chemistry. Here, I conducted four years of organic and organometallic chemistry research designing ligands for radioanalytical separations. This research resulted in a passion for overcoming the current limitations of nuclear energy. As a result, I decided to pursue my PhD in this field. Prior to beginning my PhD, I held a Graduate Research Aide position at Argonne National Laboratory where I was able to conduct research that would aide in forensic analysis of nuclear materials. I am currently a Seaborg Fellow at Los Alamos National Laboratory where I develop fundamental actinide separations to support the weapons mission. An in-depth look at my various research projects can be found here.

In addition to research, I want to bridge the gap between the scientific community and the public to provide accurate nuclear science information. Since public perception of nuclear technology is generally negative, this affects the funding that allows for further scientific advancement and bringing in a new generation of skilled nuclear workers. Using my rare, combined skillset of radiochemistry and radiation health physics, which studies radiation interactions to improve radiation safety, I can describe nuclear processes while addressing health and safety implications.

When I’m not in the lab, I can be found immersing myself in nature while camping around the country. Mindfulness plays a critical role in my life, and I have recently gained an interest in learning tea ceremony from various regions to achieve this. As a former quality control chemist at Evolution Craft Brewery, Colorado has been the perfect home to explore the world of craft brewing. In a typical day, my mornings are spent at coffee shops with books and my evenings are spent with a glass of wine and more books.

Research

Minor Actinide Separations

Minor actinides (e.g. americium, curium) are radioactive elements that are generated in small amounts in nuclear reactors. In nuclear waste, these energy-dense radionuclides can be retrieved and used as nuclear fuel to generate additional clean energy while reducing the radiotoxicity and storage lifetime of waste. Additionally, these radionuclides provide a route to improve computational simulations of nuclear weapon detonations, this data is obtained using the Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Lab. To achieve this, radiochemical processing is necessary to understand the amount of minor actinides produced. While the separation of these elements is fundamental, nearly identical chemistry of these radionuclides hinders success. However, differing oxidation states of these radionuclides can be exploited to facilitate separation. This project explores the potential of different oxidizing agents in solid-liquid extraction systems that could be implemented on both a laboratory and industrial scale.

Synthesis of a Water-soluble BTzBP Ligand for Lanthanide and Actinide Separations

Just as the minor actinides discussed above are present in nuclear waste, so too are the lanthanide elements. Prior to actinide separations, the lanthanides need to be separated from the actinides because they act as a fuel “poison” by capturing neutrons and decreasing the efficiency of energy production. In another application, these neutron capture reactions occur in Red Giant Stars (the s-process) resulting in the production of heavy elements. Obtaining these values gives an understanding of the abundance of heavy elements and the neutron density in stars, which is crucial in understanding the evolution of Giant stars and the universe. These separations are also hindered by similar chemical properties and extensive research exploring organic molecules that preferentially bind to one over another has been published. These methods, however, suffer from slow rates of extraction, insufficient solubility, and hydrolytic/radiolytic instability. It has been found that nitrogen-based ligands preferentially bind to the actinides over the lanthanides, thus this project developed the first water-soluble nitrogen-donor BTzBP ligand that may potentially be used to facilitate this separation. The results of this study were published in Synlett.

Performance of the BTzBP Ligand for Ln/An Separations

Continuing the BTzBP research beyond synthesis, I am determining the performance of this ligand and its potential for achieving successful lanthanide and actinide separations. These separations are often carried out in liquid-liquid, or solvent extraction, systems. These systems contain two layers, organic and acidic aqueous, that do not mix. Nuclear waste dissolved in acid comes into contact with the organic layer through vigorous shaking. The organic layer contains a ligand that is selective for both lanthanides and actinides and, after shaking, extracts both into the organic layer. The water-soluble BTzBP ligand is then introduced into the aqueous layer and, after another vigorous shaking, the actinides are extracted back into the acid thus resulting in the separation. This project explores how successful the BTzBP ligand is at separating the two, and will determine the optimal system conditions that produce the most efficient separation.

Improving the Recovery of Ba on Sr Resin Using Chelating Agents

The gamma radiation from the radioactive isotope, cesium-137, is useful for many applications in industry such as radiotherapy, density gauges, and well-logging devices. Unfortunately, it is also a material that can be used in radiological dispersal devices (RDDs), or “dirty bombs”. When finding Cs-137 outside of regulatory control, knowing where it came from is crucial. As Cs-137 decays, it produces stable Ba-137. The “age”, or the time since production, is determined using the ratio of Cs-137 and its daughter, Ba-137. Since manufacturers produce Cs-137 at different times, knowing the age of production can help us understand its point of origin. To determine this ratio, the two must be completely separated and measured. Previous procedures have poor recovery of Ba-137, resulting in a large uncertainty in age. This project improved the recovery of Ba-137 to decrease the uncertainty in Cs-137 age. The results of this study were published in the Journal of Radioanalytical and Nuclear Chemistry.

CV

My CV can be viewed here.

Thanks for Stopping by!

• Email
samantha.labb@colostate.edu

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Elements

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