IONIC LIQUIDS AS REPLACEMENTS FOR N-DODECANE: A COMPUTATIONAL STUDY OF SOLVENT EFFICACY IN THE PUREX PROCESS

This study investigates the potential of ionic liquids as alternative solvents to the volatile n-dodecane used in the PUREX process for separating uranium and plutonium from spent nuclear fuel. Using the COSMO-RS method, 2106 ionic liquids were screened to evaluate their suitability. Key parameters, including the distribution coefficients of uranyl nitrate in an ionic liquid/aqueous nitric acid biphasic system and the solubility of these ionic liquids in water, were assessed. Seventeen ionic liquids, particularly those based on tetrafluoroborate (BF4), were identified as highly hydrophobic. Among these, hexamethyl guanidium tetrafluoroborate demonstrated the highest distribution coefficient, surpassing that of conventional n-dodecane despite its increased hydrophilicity. The findings indicate that certain ionic liquids hold promise as effective replacements for n-dodecane in the PUREX process, potentially enhancing solvent performance in nuclear fuel reprocessing