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DECONTAMINATION ON VARIOUS SURFACES USING ION-EXCHANGE

ABSTRACT

Radioactive contamination poses several cleanup problems including: safety of cleanup

personnel, control of waste volume and end state contamination level. In an effort to

address these problems we have investigated the use of ion-exchange resin preparation

technology to treat contaminated surfaces. A variety of surfaces were contaminated with

various radionuclides. These surfaces were decontaminated with ion-specific, patent

pending, “mass effect” water based solutions, treating the surface as if it were an ion

exchange resin. The study demonstrates the ability of “mass effect” solutions to lift

radionuclides from various surfaces. Combining the “mass effect” solution with ionspecific

resins creates a mixture that lifts the contamination from the surface and can

capture it on the resin bead. This reduces cleanup time; controls waste volume and leave

the surface in a state where no more counts are removable.

INTRODUCTION

Ion-exchange resins have long been used for wastewater cleanup and radionuclide

separation. The preparation of these resins often involves activation of the resin by

altering the functional groups on the resin. For example in order to create a resin which

will capture iodine, the resin in the chloride form must be stripped of chlorine and

substituted with a functional group with lower electro negativity such as salicylate or

citrate [1]. The functional group attachment is reversible so by using high concentrations

and/or larger volumes of these reactive groups, the chloride ion is forced to leave the

resin due to the shear number of replacement ions competing for the site that the chlorine

is bound to, the “mass effect”. It is postulated that cleanup of contaminated surfaces

would be facilitated by the use of similar methods, treating the contaminated surface as

an ion exchange resin and using competing ions to displace the contamination. Mixing

specific ion exchange resins with the solution creates an alternate deposition site for the

radionuclide on a particle, which can then be removed from the surface.