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

Patent · 31 December 1998

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: WESTINGHOUSE SAVANNAH RIVER CO
• 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

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