Isolation of Soluble 99Tc as a Compact Solid Using a Recyclable, Redox-Active, Metal-Complex Extractant

We are investigating a new paradigm in separation science, the use of recyclable, redox-active metal-complex extractants for the removal and isolation of ionic contaminants from acidic, neutral, or alkaline aqueous solutions. In this paper, we report a novel process for the extraction and recovery of TcO{sub 4}{sup -}. The noteworthy features of the process are that (i) technetium is recovered as a solid of minimal volume, (ii) the extractant and the organic solvent are recovered unchanged and can be reused many times, and (iii) the expendable chemicals are readily available, inexpensive, easy to handle, and relatively nontoxic. The key element of the process is a lipophilic, redox-active, metal-complex anion extractant, 1,1`,3,3`-tetrakis(2-methyl-2-hexyl)ferrocene, 1. 21 refs., 1 fig., 3 tabs.