PROCEDE D'EXTRACTION SANS SOLVANT DES POLLUANTS ORGANIQUES ET METALLIQUES

The present invention relates to a method of treating aqueous effluents that employs an organic-solventless liquid/liquid extraction which allows the organic and metallic pollutants to be extracted by virtue of their solubilization in mixed micelles. These mixed micelles, which are formed of ionic and nonionic surfactants, are capable of simultaneous extraction of the organic and metallic pollutants. The method essentially comprises the steps consisting in: a)- preparing a solution consisting of an ionic surfactant and of at least one nonionic surfactant, b)- contacting the effluent with said solution, c)- stirring the mixture, and if necessary heating to a temperature greater by at least 1°C than the cloud point of said mixture, d)- carrying out phase separation until there are two aqueous phases, one being the phase concentrated with metallic pollutants and optionally with organic pollutants, and the other being the dilute phase, e)- recovering the two phases separately. The method according to the invention is simple, quick to implement and economic in terms of energy. The reduction in polluted volumes without production of new pollution is also a very advantageous result. The method makes it possible, moreover, to regenerate the surfactants for subsequent use, and also to recover the compounds extracted, which can be stored directly as ultimate waste or utilized for other purposes. The method may also be carried out in accordance with a continuous procedure, on the same site at which the effluents are produced.