Method for digesting spent ion exchange resins and recovering actinides therefrom using microwave radiation

Patent · Fri Jan 01 00:00:00 EST 1999

OSTI ID:872488

Nichols, Sheldon T ^[1]

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1. Augusta, GA

The present invention relates to methods for digesting diphosphonic acid substituted cation exchange resins that have become loaded with actinides, rare earth metals, or heavy metals, in a way that allows for downstream chromatographic analysis of the adsorbed species without damage to or inadequate elution from the downstream chromatographic resins. The methods of the present invention involve contacting the loaded diphosphonic acid resin with concentrated oxidizing acid in a closed vessel, and irradiating this mixture with microwave radiation. This efficiently increases the temperature of the mixture to a level suitable for digestion of the resin without the use of dehydrating acids that can damage downstream analytical resins. In order to ensure more complete digestion, the irradiated mixture can be mixed with hydrogen peroxide or other oxidant, and reirradiated with microwave radiation.

• Research Organization: Savannah River Site (SRS), Aiken, SC (United States)
• DOE Contract Number: AC09-89SR18035
• Assignee: Westinghouse Savannah River Company (Aiken, SC)
• Patent Number(s): US 5945342
• OSTI ID: 872488
• Country of Publication: United States
• Language: English

Related Subjects

method
digesting
spent
exchange
resins
recovering
actinides
therefrom
microwave
radiation
relates
methods
diphosphonic
acid
substituted
cation
loaded
rare
earth
metals
heavy
allows
downstream
chromatographic
analysis
adsorbed
species
damage
inadequate
elution
involve
contacting
resin
concentrated
oxidizing
closed
vessel
irradiating
mixture
efficiently
increases
temperature
level
suitable
digestion
dehydrating
acids
analytical
ensure
complete
irradiated
mixed
hydrogen
peroxide
oxidant
reirradiated
hydrogen peroxide
cation exchange
heavy metal
microwave radiation
exchange resin
rare earth
earth metal
exchange resins
heavy metals
earth metals
phosphonic acid
diphosphonic acid
oxidizing acid
recovering actinide
acid substituted
involve contacting
/436/204/423/