Actinide Separations Tailored for Californium-252, Plutonium-238, and Promethium-147 Campaigns

Dr. Lætitia H. Delmau, Radioisotope Science and Technology Division, Oak Ridge National Laboratory

UT Resource Center, 1201 Oak Ridge Turnpike, Oak Ridge, or view online via Zoom at 

https://us02web.zoom.us/j/82591646006?pwd=VL0GP2R6aUJdA2OAt4kqFNYf4a9X4d.1

 

Talk begins at 12 noon (EDT)

Doors open at 11:15 a.m. for socializing and eating lunch (light lunch will be available for a donation). Scroll down for details of the location, lunch, and Zoom.

 

Abstract

Plutonium-238, californium-252, and promethium-147 campaigns are the main hot cell production activities conducted at the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL). Each campaign comprises many process steps that had to be developed or improved upon to optimize the product quality or quantity. Californium campaigns are conducted every other year to produce nominally ~100 mg of californium-252, tens of milligrams of berkelium-249, and micrograms of einsteinium. Produced from the irradiation of curium targets in the High Flux Isotope Reactor, californium requires several processing steps to be obtained in a purity adequate for wire fabrication. Similarly, following the irradiation of neptunium-237 targets, many processes are required to obtain plutonium-238 that meets the specifications to produce radioisotope thermoelectric generators for NASA and to recycle the neptunium. The frequency of plutonium production campaigns is expected to be much higher with several campaigns every year. Now harvested from plutonium-238 production campaign waste solutions, promethium-147 is also produced at ORNL, which is the sole source of this isotope worldwide. In all three cases, separation processes are tailored to obtain the desired isotopes with the target purity while meeting tight schedules. 

 

Biographical Sketch

Dr. Lætitia H. Delmau, a distinguished radiochemist at Oak Ridge National Laboratory, is the 2024 winner of the prestigious Glenn T. Seaborg Actinide Separations Award for her contributions to actinide separations. She graduated from the Ecole Superieure de Physique et de Chimie Industrielles de la ville de Paris in 1994 with a master’s degree in chemical engineering and a post-master’s degree in radiochemistry. She received her Ph.D. in physical chemistry from the University Louis Pasteur of Strasbourg, France, while conducting her research studies at the Commissariat à l’Energie Atomique (CEA) in Cadarache. In October 1997, she joined ORNL as a postdoctoral researcher in the Chemical Separations Group (CSG) in the Chemical Sciences Division; CSG hired her in 2000. She worked within the Critical Material Institute and the Fuel Cycle Research and Development Program (STAAR), focusing on isotope separations primarily using solvent extraction or ion exchange chromatography. 

 

She helped develop a solvent extraction process to remove highly toxic cesium-137 from the high-level waste stored at the Savannah River Site; as a result, the industrial process developed under ORNL leadership is now used at the facility. She and the rest of the Salt Waste Disposal Technologies Team received the DOE Secretary’s Achievement Award in 2013. The next year she moved to ORNL’s Radioisotope Science and Technology Division. 

 

For the past 10 years, Lætitia has been involved in developing new processes for improving the quality and quantity of the production of plutonium-238, californium-252, and more recently promethium-147, a high-purity batch of which was used by her colleagues to make new discoveries about promethium that were published in the May 2024 edition of the prestigious scientific journal Nature. In 2022, she was part of the team that produced plutonium-238 for the radioisotope thermoelectric generator that since 2020 has been powering NASA’s Perseverance Rover on the planet Mars. Her work on the 2020 Mars Perseverance Rover Radioisotope Power Systems Team enabled her to receive her second DOE Secretary’s Achievement Award “for service and contributions to the Department’s mission and for the benefit of the nation.” This year she received the Seaborg Actinide Separations Award, thanks partly to the nomination by her colleague Jeff Delashmitt of ORNL’s Chemical Sciences Division who hailed her behind-the-scenes influence on a complex field.

Laetitia Delmau

Event Details

The UT Resource Center is at 1201 Oak Ridge Turnpike between Dairy Queen and Applebee's Grill. Use the entrance at the southwest (back) corner of the building. 

A light lunch (half sandwich, chips, cookie, and a drink) will be available for a $10 donation (cash, check or IOU) starting about 11:15 a.m. on a first-come, first-served basis.   Attendees may also bring food to eat.

 

Meeting Agenda
11:15 a.m.  – Arrive at UT Resource Center to grab a light lunch or chat with colleagues
11:50 a.m.  – Zoom attendees may login and chat with those online until noon
12:00 p.m. – Talk begins following a few announcements and introduction of the speaker.
 

Zoom available about 11:50 a.m.

https://us02web.zoom.us/j/82591646006?pwd=VL0GP2R6aUJdA2OAt4kqFNYf4a9X4d.1

Meeting ID: 825 9164 6006   Passcode: 978849