Recovery of uranium by tannin immobilized on matrices which have amino group

Tannin, which contains polyhydroxy groups, has a high affinity for uranium. Various tannin–protein complexes were prepared to develop new adsorbents for uranium recovery from seawater. Albumin tannate has a high ability to adsorb uranium from seawater. Tannin was immobilized on matrices which have multiple active amino groups, such as aminopolystyrene and poly(vinyl‐4,6‐diamino‐s‐triazine)—poly VT. Of these complexes, tannin immobilized on poly VT adsorbed uranium most efficiently from seawater and highly selectively from a solution containing various heavy metals; the uranium adsorption was very rapid and was pH dependent. This adsorbent therefore appears to have potential for use in a commercial process for uranium recovery from seawater or from uranium‐containing waste water.