Even so, key gaps in fundamental knowledge stood in the way of developing a functional industrial process, and this is where the expertise of the ORNL scientists came in. First, a soluble calixarene-crown extractant would have to be synthesized. A critical step was the use of special fluorinated alcohols that enhance BOB Calix's extraction strength, allowing the expensive extractant to be effective at economical concentrations. One of the alcohols is shown below. This closed the cycle, allowing the solvent to be used over and over again.
Picture shows end-on view with foreground atoms deleted.
Recently, the process was selected as one of four top technologies for possible application at the Savannah River Site, where the process was shown in engineering evaluations to be competitive with the alternative technologies. One of the recognized advantages of alkaline-side CSEX is that the process would give a product stream that contains nearly pure cesium nitrate, an ideal feed for subsequent vitrification with concomitant major cost savings to the U.S. taxpayer. The purity of the 137 Cs product also suggests possible uses in gamma sources for industrial applications. This work was recognized by a 1999 Lockheed Martin Technical Accomplishment Award. Applied and fundamental research related to alkaline-side CSEX are continuing.