The Nonlinear Dynamics of CUC12/A1 in Nitric Acid Solution: Chloride Ion Concentration

Abstract

The Purex (Plutonium/Uranium Extraction) process employs environmentally hazardous mercury salts and organic solvents to separate plutonium and uranium from fission products. During this dissolution process, observations showed that the system was effectively dependent on the available mercury. After further investigation, the Purex process was found to be fundamentally electrochemical—that is, electron transfer from one chemical species to another occurs. Similar electrochemical behavior is observed when solid aluminum (Al) is placed in a solution of solid copper(II) chloride (CUCI2) and 3.0 M nitric acid (HN03). In addition, dissolution of aluminum occurs in the CUC12/HN03 solution. These characteristics are of interest because this new system behaves similarly to the current Purex process, and it potentially represents an environmentally-friendly method of plutonium/uranium extraction from nuclear waste materials. The primary goal of this project is to investigate the oscillatory nature of the CUC12/A1 system in hopes of obtaining a critical mass of data suitable to complete a full physical study of this system, with the final goal of finding an environmentally-suitable alternative to the current Purex process. In this paper, the electrochemical oscillations are monitored as a function of chloride concentration. My research resulted in discovering a qualitative relationship between the voltage (amplitude), frequency, and consistency of these oscillations with the amount of chloride ion (CP) present. This research also further verified the chloride ion's importance in the electrochemical process as well as that of mass transport.