Potential for the Use of Hydrochloric Acid in Fission Reactor Fuel Recycle

Abstract

The chemistry and the effects of the use of hydrochloric acid (HCl) as the aqueous phase in fuel recycle are surveyed. Available data are sufficient to suggest that the separation of actinides and fission products in an HCl-trialkylamine system can be at least equal to that in the Purex process. Advantages of the HCl system are: simpler operation of the off-gas system, better separation of neptunium from uranium and plutonium, better control of the oxidation states of the dissolved species, and simpler recycle of the acid. A possible advantage is more complete dissolution of the fission products, leaving very little insoluble residue. Disadvantages include: the lack of development of methods for dissolution of oxide fuel in HCl, the sparsity of distribution data, the requirement for processing equipment constructed of tantalum, possible complications in the waste-handling system, and the dissolution of much of the cladding in the case of stainless-steel clad fuel. Systems using HCl are not attractive as replacements for Purex; however, there may be advantages to their use in some special applications.