The Development and Properties of an Adsorbent for Uranium

Abstract

An adsorbent for uranium was developed by placing upon the surface of a porous char an organic substance which has a very low aqueous solubility and a strong tendency to form chelate compounds with uranium under the solution conditions at which uranium adsorption is desired. The quantity of uranium adsorbed from a sulfuric acid solution onto char modified with di-2-ethylhexyl pyrophosphate is on the order of ten times that obtained on unmodified char. Activity and capacity of a modified adsorbent are observed to be dependent on the modifier selected, the surface concentration of the modifier, and the nature of the char adsorbent. The experimental behavior of the modified adsorbents supports the assumption that adsorption occurs by formation of a uranyl chelate compound with the modifier at the surface of the adsorbent and that the adsorptive capacity of the modified adsorbent for uranium is limited by steric considerations determined by the size of the chelate molecule being formed and the pore size distribution of the adsorbent.

Studies on Uranium Recovery by Activated Carbon Impregnated With Tridodecylamine and Tributyl Phosphate

“…In fact, the activated carbon can be considered as the most effective and economic support. Charcoals impregnated with organophosphorus compounds (Byler and Maclain, 1995;Noble et al, 1958;Maclain et al, 1958) and organic amines (Goren, 1967) were investigated for the recovery of uranium from acid leach liquors.…”

Uranium Adsorption from Leach Slurries

“…Previous investigations (2,3) indicated the chelating agent must be a strong acid, form a strong chelate with uranium, be water-insoluble, and meet molecular size and spatial requirements for' strong adsorption to a suitable surface. The organophosphorus acids generally fulfilled these requirements and di-2-ethylhexyl pyrophosphate (OPPA) was selected for this study.…”