The TRUSPEAK Concept: Combining CMPO and HDEHP for Separating Trivalent Lanthanides from the Transuranic Elements

Journal Article · Mon Apr 08 04:00:00 EDT 2013 · Solvent Extraction and Ion Exchange, 31(3):223-236

DOI:https://doi.org/10.1080/07366299.2012.670595· OSTI ID:1082594

Lumetta, Gregg J.; Gelis, Artem V.; Braley, Jenifer C.; Carter, Jennifer C.; Pittman, Jonathan W.; Warner, Marvin G.; Vandegrift, George F.

Combining octyl(phenyl)-N,N-diisobutyl-carbamoylmethyl-phosphine oxide (CMPO) and bis-(2-ethylhexyl) phosphoric acid (HDEHP) into a single process solvent for separating transuranic elements from liquid high-level waste is explored. Co-extraction of americium and the lanthanide elements from nitric acid solution is possible with a solvent mixture consisting of 0.1-M CMPO plus 1-M HDEHP in n-dodecane. Switching the aqueous-phase chemistry to a citrate-buffered solution of diethylene triamine pentaacetic acid (DTPA) allows for selective stripping of americium, separating it from the lanthanide elements. Potential strategies for managing molybdenum and zirconium (both of which co-extract with americium and the lanthanides) have been developed. The work presented here demonstrates the feasibility of combining CMPO and HDEHP into a single extraction solvent for recovering americium from high-level waste and its separation from the lanthanides.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1082594
• Report Number(s): PNNL-SA-81137; AF5805000
• Journal Information: Solvent Extraction and Ion Exchange, 31(3):223-236, Journal Name: Solvent Extraction and Ion Exchange, 31(3):223-236
• Country of Publication: United States
• Language: English

Related Subjects

CMPO
HDEHP
actinide separation
lanthanide separation
lanthanide/actinide separation