Symmetric and asymmetric dithiophosphinic acids for minor actinide extraction

INOR 964

John R. Klaehn, john.klaehn@inl.gov1, Dean R. Peterman, dean.peterman@inl.gov2, Mason K. Harrup, mason.harrup@inl.gov1, Richard D. Tillotson, tillrd@inel.gov2, Thomas A. Luther, thomas.luther@inl.gov1, Mitchell R. Greenhalgh2, Jack D. Law, Jack.Law@inl.gov2, and Lee M. Daniels, ldaniels@RigakuMSC.com3. (1) Department of Chemical Sciences, Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-2208, (2) Aqueous Separations and Radiochemistry Department, Idaho National Laboratory, Mail Stop 7113, Idaho Falls, ID 83415-7113, (3) Rigaku/MSC, Inc, 9009 New Trails Dr, The Woodlands, TX 77381
Several dithiophosphinic acid (DPAH) derivatives have been isolated using a synthetic pathway which provides the control of regiochemistry and/or stereochemistry of the products. The synthetic pathway also provides an accessible route for both symmetric and asymmetric DPAH derivatives (two different substituents on phosphorus). In addition, the synthesis improves DPAH designs that can address the issues about the separation between trivalent actinides and lanthanides. Some of the DPAH products showed remarkable stability when exposed to the atmosphere for long periods. For example, bis(o-trifluoromethylphenyl)dithiophosphinic acid (1) showed very little degradation when contacted with water and nitric acid for prolonged periods. One astonishing finding is that 1 selectively extracts trivalent actinides from lanthanides at higher acidities with separation factors of over 100,000 at low pH. The synthesis and characterization along with some stability testing and Ln(III)/An(III) extraction results will be presented.
 

Chemistry of Lanthanides and Actinides
1:30 PM-3:30 PM, Thursday, August 23, 2007 BCEC -- 204 A/B, Oral

Division of Inorganic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007