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Actinide Separations Conference Program, May 2021

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Actinide 2021 44TH ANNUAL Separations CONFERENCE Tuesday–Thursday May 18–20, 2021 pnnl.cvent.com/ASC2021 Times denoted are Pacific Daylight Time Welcome to the 44th Annual Actinide Separations Conference Hosted virtually by Pacific Northwest National Laboratory After postponing the Actinide Separations Conference one year because of the COVID-19 global pan- demic, we are pleased to offer this online experience to connect with colleagues and share exciting developments in actinide and separations chemistry. Who would have guessed two years ago, when we started planning the ASC to be held at PNNL in Washington State, that we would be gathering over Zoom? The silver lining of the virtual conference is that more of us can attend and present this year because of the flexibility offered by the online platform. We also are pleased to hold an interactive virtual poster session on Wednesday afternoon, and hope you’ll take time to drop in. The complexities of actinide and separations chemistry are reflected in the diverse subjects of the technical program. We are looking forward to valuable and informative interchanges on topics such as molten salt chemistry, plutonium processing, critical materials, metal-organic frameworks, solvent extraction, spent nuclear fuel recycling, and medical isotopes. We encourage you to take this opportunity to learn more about your particular areas of expertise and to explore areas different than your immediate research interests. The success of this conference ultimately is because of the scientists and engineers willing to share information, ask questions, and engage actively in discussion. We thank PNNL for providing the virtual venue and administrative support. We especially thank you, the participants in the 44th Actinide Separations Conference, for your involvement. We look forward to gathering in person next year. Conference Chairman Gregg Lumetta Conference Coordinator Becky Ford Technical Program Chairman Gabriel Hall Conference Administrator Crystal Rosales 2 Advisory Board Members Candido Pereira, Argonne National Laboratory Jack D. Law, Idaho National Laboratory Kiel Holliday, Lawrence Livermore National Laboratory Casey Finstad, Los Alamos National Laboratory Laetitia H. Delmau, Oak Ridge National Laboratory Gregg J. Lumetta, Pacific Northwest National Laboratory Tracy Rudisill, Savannah River National Laboratory Mark P. Jensen, Colorado School of Mines Mike Simpson, University of Utah 2 3 Conference Schedule Times denoted in Pacific Daylight Time Tuesday, May 18 Thursday, May 20 8:00 am Welcome 7:55 am Announcements 8:10 am Tech Session 1 8:00 am Tech Session 7 Pyrochemical and Molten Salt 1 Pyrochemical and Molten Salt 3 10:15 am Break 9:40 am Break 10:30 am Tech Session 2 9:55 am Tech Session 8 Plutonium Processing Medical Isotopes 12:10 pm Lunch break 12:00 pm Lunch Break 13:30 pm Tech Session 3 13:30 pm Tech Session 9 Pyrochemical and Molten Salt 2 15:35 pm Break 15:35 pm Break 15:50 pm Tech Session 10 15:50 pm Tech Session 4 17:05 pm Seaborg Award and Closing Remarks 17:35 pm Closing Remarks for Day 1 17:35 pm ASC Conference Concludes Wednesday, May 19 7:55 am Announcements 8:00 am Tech Session 5 Solvent Extraction 1 10:05 am Break We look forward to seeing you online! If you have any technical questions, 10:20 am Tech Session 6 Solvent Extraction 2 please contact Gregg Lumetta ([email protected]) or 12:00 pm Lunch break; ASC Board Meeting (closed session) Gabe Hall ([email protected]). Logistical questions can be addressed 13:30 pm Virtual Poster Session opens (special Zoom link) to Becky Ford ([email protected]) 15:00 pm Virtual Poster Session closes 4 THE GLENN T. SEABORG Actinide Separations Award 1984 Glenn T. Seaborg, University of California at Berkeley 1985 Don E. Ferguson, Oak Ridge National Laboratory 1986 Larned B. Asprey, Los Alamos National Laboratory 1987 Wallace W. Schulz, Westinghouse Hanford Company 1988 Lawrence J. Mullins, Los Alamos National Laboratory 1989 Gregory R. Choppin, Florida State University 1990 Donald A. Orth, Westinghouse Savannah River Company 1991 David O. Campbell, Oak Ridge National Laboratory 1992 E. Philip Horwitz, Argonne National Laboratory 1993 Earl J. Wheelwright, Pacific Northwest Laboratory 1994 Leslie Burris, Argonne National Laboratory 1995 Robert R. Penneman, Los Alamos National Laboratory 1996 David G. Karraker, Westinghouse Savannah River Company 1997 Major C. Thompson, Westinghouse Savannah River Company 1998 Walter D. Bond, Oak Ridge National Laboratory 1999 Jack L. Ryan, Pacific Northwest National Laboratory 2000 John L. Swanson, Pacific Northwest National Laboratory 2001 George F. Vandegrift, Argonne National Laboratory 2002 Leonard W. Gray, Lawrence Livermore National Laboratory 2003 Kenneth L. Nash, Argonne National Laboratory 2004 Emory D. Collins, Oak Ridge National Laboratory 2005 Terry A. Todd, Idaho National Laboratory 2006 Renato Chiarizia, Argonne National Laboratory 2007 Leland L. Burger, Pacific Northwest National Laboratory 2008 Gordon D. Jarvinen, Los Alamos National Laboratory 2009 Raymond G. Wymer, Oak Ridge National Laboratory 2011 Darleane C. Hoffman,University of California-Berkeley 2012 Jimmy T. Bell, Oak Ridge National Laboratory 2013 Lane A. Bray, Pacific Northwest National Laboratory 2014 David T. Hobbs, Savannah River National Laboratory 2015 Gregg J. Lumetta, Pacific Northwest National Laboratory 2016 Guillermo (Bill) Del Cul, Oak Ridge National Laboratory 2017 Tracy Rudisill, Savannah River National Laboratory 2018 Jack D. Law, Idaho National Laboratory 2019 Bruce A. Moyer, Oak Ridge National Laboratory 4 5 2021 – Mark Jensen Mark Jensen is Professor of Chemistry and the Jerry and Tina Grandey University Chair in Nuclear Science and Engineering at the Colorado School of Mines. Prior to assuming this position in 2015, he was a staff scientist in the Heavy Elements and Separations Science Group at Argonne National Laboratory. Mark’s interest in actinide science and separations started as an under- graduate student in the ACS/DOE Nuclear Chemistry Summer School, which was followed by a summer internship in the Heavy Elements Chemistry Group at Argonne trying to make a superconducting Pu compound. In 1994 he earned a Ph.D. in inorganic and nuclear chemistry at Florida State University with Greg Choppin, using solvent extraction to study the composition and stability of environmentally relevant actinide and lanthanide complexes. After completing his dissertation, Mark moved to Argonne where he was a post- doctoral research associate mentored by Phil Horwitz and Ken Nash studying a range of separation systems. Starting as a staff scientist at Argonne in 1995, Mark’s research initially focused on understanding separa- tions of trivalent actinides from lanthanides, which led to his first presentation at an Actinide Separations Conference in 1996, Solvent Extraction Separations of Trivalent Lanthanide and Actinide Ions Using Heterocycle Substituted Methanediphosphonic Acids, which examined the potential for separation of the size-matched actinide and lanthanide cations Cf3+ and Eu3+. The importance of ligand hydration in these complexes sparked an interest in how the particular complexes formed in different separation systems drive selectivity in actinide separations. This led to series of fundamental studies on actinide and lanthanide complexes of sulfur- and nitrogen-containing ligands, including foundational structural studies of Am and Cm extractant complexes and key thermodynamic studies of americium complexes with nitrogen-containing ligands. More recently, his long-standing interest in these separations resurfaced in work on modifications to the ALSEP process to enable separation of Am from Cm and the lanthanides or improve the stripping kinetics. This interest in the complexes formed in actinide separations created opportunities with colleagues from Argonne as well as domestic and international collaborators for key experiments examining how organic phase complexes evolve with changes in the organic phase caused by phase splitting, substitution of ionic liquids for molecular diluents, sorption on chromatographic supports, or aggregation. More recently, Mark has been examining ways to co-opt features of metal-binding proteins and peptides to enable novel approaches to separating actinide elements. His work has probed conformationally-switched actinide discrimination, attempted to engineer bacteria to take up actinides, and identified a dozen possible new plutonium-binding proteins, some of which have distinct secondary interactions with receptors suitable for separations. He has shown the conformationally-switched separation of plutonium by the protein trans- ferrin to be delightfully intricate, requiring interactions between two proteins and multiple small molecule ligands that are mediated by ligand-ligand interactions in the outer coordination sphere of the actinide complexes to achieve separation. Dr. Jensen is the coauthor of 80 peer-reviewed journal papers, 25 peer-reviewed conference papers, and 3 book chapters, and has served as an associate editor of the journal Solvent Extraction and Ion Exchange since 2002. 6 TUESDAY, May 18, 2021 Times denoted in Pacific Daylight Time 8:00 - 8:10 Welcoming Remarks Jud Virden, Pacific Northwest National Laboratory Tech Session 1 – Pyrochemical and Molten Salt 1 Session Chair: Marisa Monreal, Los Alamos National Laboratory 8:10 - 8:35 The Development of Vacuum Salt Distillation at AWE Richard Driscoll, AWE Dr R J P Driscoll, AWE, Aldermaston, RG7 4PR,
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