Process for separating metals by micellar ultrafiltration, usable for treating radioactive effluents

Recovering a metal from an aqueous solution comprises adding an aqueous solution of a complex forming anionic surfactant of specified formula and filtering off the micelles formed using an ultrafiltration membrane. Separating at least one metal from an aqueous solution comprises adding an aqueous solution of a complex-forming anionic surfactant of formula MCOO-(CH2)m-CH(NHCOR)-COOM (I), where: M = a monovalent cation; m = 1 or 2; and R = a linear or branched, saturated or unsaturated aliphatic group with at least 8C in an amount sufficient to form micelles in the solution and subsequently filtering the solution through an ultrafiltration membrane capable of retaining the micelles formed. Independent claims are included covering: (a) a process in which the metals to be separated are selected from thorium, uranium, ruthenium and the transuranium elements; and (b) a process in which the aqueous solution to be treated is a radioactive effluent. L'invention concerne un procédé de séparation des métaux par ultrafiltration micellaire, utilisable pour le traitement d'effluents radioactifs. Ce procédé consiste à ajouter à la solution aqueuse un tensioactif anionique complexant de formule : M = cation, par exemple Na, m = 1 ou 2, R = groupe aliphatique d'au moins huit atomes de carbone, et éventuellement un tensioactif non ionique comme le Triton X-100 ou le Brij 35 pour former des micelles (10) dans la solution, et filtrer ensuite la solution sur une membrane d'ultrafiltration (3) pour retenir les micelles formées précédemment.