ABSTRACT
Activated carbon beds can be used for the removal of many of the extractants. To make up for the loss of extractant in the resin particles, reintroduction of the extractant is practiced. Farbenfabriken Bayer terms these extracting resins "Levextrel®". Some of the extractants that may be used are aliphatic amines, phosphoric esters, and both alipatic and aromatic oximes. The beads have a low bulk density and very low specific gravity. The extractant can be 25 to 50% of the bulk weight. Since the extractant is hydrophobic, the resin has a very low water retention. The selectivity of the products depends on the extractant and the ions involved. Thus, the variety of products that can be made available is limited only by the number of liquid ion exchangers or liquid extractants available. The resins are an improvement over the liquid/liquid extraction process in that they eliminate the problem of phase separation.
