George Robert Mason

US Patent:

41622308, Jul 24, 1979

Filed:

Dec 28, 1977

Appl. No.:

5/865346

Inventors:

E. Philip Horwitz - Elmhurst IL
Walter H. Delphin - Woodridge IL
George W. Mason - Clarendon Hills IL

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

G21F 904
G21F 906

US Classification:

2523011W

Abstract:

A process for partitioning and recovering actinide values from acidic waste solutions resulting from reprocessing of irradiated nuclear fuels by adding hydroxylammonium nitrate and hydrazine to the waste solution to adjust the valence of the neptunium and plutonium values in the solution to the +4 oxidation state, thus forming a feed solution and contacting the feed solution with an extractant of dihexoxyethyl phosphoric acid in an organic diluent whereby the actinide values, most of the rare earth values and some fission product values are taken up by the extractant. Separation is achieved by contacting the loaded extractant with two aqueous strip solutions, a nitric acid solution to selectively strip the americium, curium and rare earth values and an oxalate solution of tetramethylammonium hydrogen oxalate and oxalic acid or trimethylammonium hydrogen oxalate to selectively strip the neptunium, plutonium and fission product values. Uranium values remain in the extractant and may be recovered with a phosphoric acid strip. The neptunium and plutonium values are recovered from the oxalate by adding sufficient nitric acid to destroy the complexing ability of the oxalate, forming a second feed, and contacting the second feed with a second extractant of tricaprylmethylammonium nitrate in an inert diluent whereby the neptunium and plutonium values are selectively extracted.

US Patent:

40162370, Apr 5, 1977

Filed:

Sep 8, 1975

Appl. No.:

5/611272

Inventors:

George W. Mason - Clarendon Hills IL
Sonia Lewey - Joliet IL

Assignee:

The United States of America as represented by the United States Energy
Research and Development Administration - Washington DC

International Classification:

C01F 1700

US Classification:

423 21

Abstract:

Production rates for solvent extraction separation of the rare earths and yttrium from each other can be improved by the substitution of di(2-ethylhexyl) mono-thiophosphoric acid for di(2-ethylhexyl) phosphoric acid. The di(2-ethylhexyl) mono-thiophosphoric acid does not form an insoluble polymer at approximately 50% saturation as does the former extractant, permitting higher feed solution concentration and thus greater throughput.

US Patent:

42083770, Jun 17, 1980

Filed:

Jul 25, 1978

Appl. No.:

5/928026

Inventors:

E. Philip Horwitz - Elmhurst IL
George W. Mason - Clarendon Hills IL

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

C02B 132

US Classification:

423 8

Abstract:

A process for rendering actinide values recoverable from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorous extractants such as tri-n butyl phosphate (TBP) and dihexyl-N,N-diethyl carbamylmethylene phosphonate (DHDECAMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is preferably made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant is recycled after stripping the degradation products with a neutral sodium carbonate solution.

US Patent:

45487901, Oct 22, 1985

Filed:

Jul 26, 1983

Appl. No.:

6/517475

Inventors:

E. Philip Horwitz - Naperville IL
Dale G. Kalina - Naperville IL
Louis Kaplan - Lombard IL
George W. Mason - Clarendon Hills IL

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

C01G 5600
C01F 1700
C01F 953
C07C10300

US Classification:

423 9

Abstract:

A process for the recovery of actinide and lanthanide values from aqueous acidic solutions with an organic extractant having the formula: ##STR1## where. phi. is phenyl, R. sup. 1 is a straight or branched alkyl or alkoxyalkyl containing from 6 to 12 carbon atoms and R. sup. 2 is an alkyl containing from 3 to 6 carbon atoms. The process is suitable for the separation of actinide and lanthanide values from fission product values found together in high level nuclear reprocessing waste solutions.