The PUREX extraction in nuclear fuel reprocessing leaves behind a nitric acid raffinate full of (mainly) 'fission products', which are a diverse set of elements produced by fission in a nuclear reactor. The concentrations of the various components of the raffinate are shown in this image.
My goal is to separate out the group III elements from the group IV+ elements (shown highlighted in red/blue). It does not matter what happens to the rest of the components, they can go with either or neither of these groups in any combination, all that matters is that the group III elements are spatially separated from the group IV+ elements. The process can be as inexact as necessary as long as it mostly accomplishes this goal.
Any thoughts? My nuclear chemistry book says that these group III elements are "have soluble nitrates, chlorides, and sulfates while their fluorides and hydroxides are insoluble. LaF3 is frequently used as a carrier for this group. They form stable complexes with strong chelating agents such as DPTA, EDTA, and the like". Perhaps this makes the question fairly straightforward, I'm coming from a physics, not a chemistry background. I'm just confused as to what properties the group III elements have that the group IV+ elements don't which could be leveraged to achieve some kind of separation.
Sorry for the wall of info, and thanks very much in advance for any help or input!