Abstract: The invention relates to the separation of lanthanides and actinides by nanofiltration complexation. The object of the invention is to satisfy the existing need for a simple, efficient and economical technique for separating lanthanides and actinides. This object is achieved by a process consisting of using ligands of the polyamino acid type, such as EDTA or DTPA, for complexing lanthanides and/or actinides before separating them by nanofiltration. The invention further relates to novel polyamino acid ligands incorporating ligand structures additional to EDTA and DTPA. Application to the production of rare earths or nuclear waste processing, especially to recycling operations carried out on spent nuclear fuels is also discussed.

Abstract: The invention concerns an epoxidized trialkylammonium salt characterised in that it is selected among salts of general formula (I), wherein: R represents a (CH2)n—A—NH—(CH2)n′—N+R1R2R3 group wherein A represents a —CO— or CH2— group; n′ and n range between 1 and 20, with n+n′ not less than 10; R1, R2 and R3 are C1-C20 alkyl or mono-hydroxyalkyl groups, linear or branched, identical or different; X represents counterion. The invention also concerns a synthesis method for said salts, the use of said salts as chemical grafting agents, a chemical grafting method for substrates and the resulting biocidal and/or bacteriostatic substrates.