Advances in ionic liquids: Synthesis, environmental remediation and reusability

Ionic liquids (ILs) are next generation solvents which are synthesized by organic salts, possess negligible vapour pressure and have low flammability. They possess high thermal and electrochemical stability, can be reused for multiple cycles, and its properties can be tuned according to the components used in its synthesis. Hence, ILs are considered to be potential alternatives for the conventional organic solvents for numerous applications such as environmental remediation, nanoparticles synthesis, as catalysts in various chemical reactions, as solvents for the extraction of biomolecules from recalcitrant lignocellulosic biomass, etc. In this review article, the holistic approach of ILs starting from various techniques adopted for its synthesis along with its critical review has been discussed followed by detailed discussion on the mechanism involved for the remediation of environmental pollutants using ILs. Further, in depth documentation of various environmental pollutants remediated till date using ILs has been done. One of the major drawbacks of solvents application is the reusability factor, and hence in this review article, techniques adopted to recycle/reuse of ILs has been discussed. Further, the adverse effect of using ILs for environmental remediation has been comprehensively discussed to present a holistic view. Future studies should focus on synthesis of environment friendly ILs and their field-scale applications for environmental remediation.