Ionic liquids and deep eutectic solvents in wastewater treatment: recent endeavours

Contamination in global water world has reached to such an extreme extent that scientist community is making tireless efforts to find the way to recycle, reuse or recirculate the wastewater by removing the sludge and other water pollutants apart. Newer water resources generation is another difficult but necessary challenge to increase the consumable water ratio in our environment which could be accomplished only by decontaminating them in a bulk measure. Ionic liquids (ILs) or deep eutectic solvents (DESs) have become unique in showing their capability of purifying or decontaminating considerable amount of water resources, be it wastewater from industries, sludge treatment or newer resources. Having some intricate and wide range of chemical properties, ILs and DESs with water-miscible, -immiscible or partially-miscible characters are becoming one of the choices of scientist community among other chemicals in solving the problem regarding removal of contaminants from water. Here in this article, we have highlighted some of the successful implementation of "green " ILs and DESs in addressing and participating in generation of consumable water by means of removal of several types of contaminants like, toxic metals and metal ions, organic wastes, surfactants, pesticides, dyestuffs, microplastics, lignocellulosic biomasses etc. It has been taken care of the concern about the possibilities of non-recovery costs of ILs and DESs in water due to usage of large amount of them which have been tried by recovering, removing or recycling them after accomplishing their decontamination role. Uniqueness, probable future prospects and the economic viability have been discussed and concluded comprehensively.