Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Extracting metals directly from metal oxides

Patent ·
OSTI ID:870847
 [1];  [1];  [1]
  1. Moscow, ID
+ Show Author Affiliations
A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones, halogenated .beta.-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process.
Research Organization:
University of Idaho
DOE Contract Number:
FG02-91ER75679
Assignee:
Idaho Research Foundation, Inc. (Moscow, ID)
Patent Number(s):
US 5606724
OSTI ID:
870847
Country of Publication:
United States
Language:
English

References (6)

Supercritical fluids offer improved separations: Gases at high pressure and above critical temperature separate compounds under mild conditions, require less energy but more capital journal August 1981
Enhanced extraction of lanthanides with crown ether carboxylic acids of increasing lipophilicity journal January 1989
Solvent extraction of dithiocarbamate complexes and back-extraction with mercury(II) for determination of trace metals in seawater by atomic absorption spectrometry journal December 1982
Extraktion mit überkritischen Gasen — ein Vorwort journal October 1978
Supercritical fluid extraction of lanthanides and actinides from solid materials with a fluorinated .beta.-diketone journal September 1993
Zum Stand der Extraktion mit komprimierten Gasen journal January 1981

Similar Records

Extracting metals directly from metal oxides
Patent · Mon Feb 24 23:00:00 EST 1997 · OSTI ID:441851
Extraction of metals using supercritical fluid and chelate forming legand
Patent · Mon Mar 23 23:00:00 EST 1998 · OSTI ID:871431
Extraction of metals using supercritical fluid and chelate forming ligand
Patent · Mon Mar 23 23:00:00 EST 1998 · OSTI ID:597116

Related Subjects

-diketones
/423/
acids
actinide
agent
agent forms
agents
allowing
benign
benign process
beta
biologically
biologically harmful
carbon
carbon dioxide
carboxylic
carboxylic acid
carboxylic acids
chelate
chelates
chelating
chelating agent
chelating agents
consisting
containing
described
dioxide
direct
directly
economic
efficient
efficient process
embodiments
environmentally
environmentally benign
especially
especially preferred
exposing
extracting
extracting metal
extracting metals
extraction
extraction solvent
fluid
fluid solvent
fluorinated
forms
forms chelates
halogenated
harmful
harmful solvents
lanthanide
metal
metal oxide
metal oxides
metals
metals directly
method
method provide
method provides
mixtures
moving metal
oxide
oxides
phosphinic
phosphinic acid
plutonium
preferably
preferred
preferred embodiment
preferred embodiments
process
provide
provides
recovered
regenerated
removal
removing
removing metal
removing metals
selected
soluble
solvent
solvent containing
solvents
supercritical
supercritical carbon
supercritical fluid
thorium
uranium