Immobilization of Technetium by Electroless Plating

摘要

A process of incorporating technetium into an electroless deposit, forming an alloy that is extremely resistant to corrosion and reduces the mobility of technetium on a geologic time scale is disclosed and claimed. The process includes providing a liquid containing technetium, such as an aqueous waste stream generated during the used nuclear fuel reprocessing activities. The technetium is collected and concentrated, and provided into an electroless deposition bath. A substrate, such as suitably prepared zero valent iron or stainless steel, is introduced into the bath to initiate autocatalytic electroless deposition of the technetium onto the substrate due to the difference in electrochemical potential between the plating bath and the metals in solution. This causes a layer of technetium metal to form on the substrate. The electroless deposition is continued until virtually all of the technetium has been removed from the bath, and then continues to build a layer of technetium-free material on the outermost surface of the substrate. One or more additional deposition steps may be performed to armor the plated substrate against leaching/corrosion in a nuclear waste disposal facility.

主权项

1. A process, comprising:
providing a radioactive waste liquid generated during reprocessing of used nuclear fuel, said liquid containing 99Tc; adding chemicals to said liquid to form an electroless plating bath; introducing a plating substrate into said bath to initiate electroless deposition of said 99Tc onto said substrate; and maintaining said substrate within said bath until substantially all of said 99Tc is removed from said bath and deposited onto said substrate.