Process for purifying or producing ionic liquids by generating an alcoholate adduct intermediate

Abstract

The present invention relates to methods for purifying or producing ionic liquids of the type Im+Y-, starting from a contaminated ionic liquid Im+X-. This ionic liquid is first mixed with a stoichiometric excess of alkali or alkaline earth metal alcoholate dissolved in an organic solvent, the alkali or alkaline earth metal salt formed in the process is then separated from the mixture, the mixture obtained after separation is reacted with an equimolar amount of acid HY to the alkali or alkaline earth metal alcoholate, and the excess salt quantities formed in the process are separated from the mixture to obtain pure ionic liquid of the type Im+ Y-. The specified process enables simple and cost-effective production, purification, and recovery of ionic liquids from industrial processes. The present invention further relates to the use of such a process for the purification and recovery of ionic liquids that have been used in wet spinning processes for the production of cellulose filaments, and to processes that include such wet spinning processes in combination with purification and recovery of ionic liquids.