Carbon Nanofibers and Other Carbon Nanostructures As Carriers of Green Solvents (Ionic Liquids) for the Pretreatment of Saline Water for Desalination

Abstract

Desalination is intensively used throughout the world as a means of reducing the current and future water scarcity caused by the increased population, industrialization and economic growth. As a rule, desalination technologies are usually implemented in coastal and arid areas that have access to seawater sources and lack surface water sources. Among the desalination technologies implemented, membrane technology is the one preferred in many projects currently due to a series of reasons, its lower environmental impact being one of them. This drive for minimizing the environmental impact, while making the whole process more efficient, generated the idea of investigating the use of some well-known green solvents, the Ionic Liquids (ILs), and their ability to extract salts from seawater as a step in the entire desalination process. However, most of the ILs, which have high solubility for some of the salts known to cause fouling problems, are hydrophilic and thus, they cannot be used directly for extraction. Studies in the literature have shown that this type of ILs will not dissolve in water, if they are properly loaded on suitable carriers. Carbon nanostructures either in the form of fibers or tubes, with their unique properties have already been used as carriers for a wide variety of chemical species.

In this work, we will present our results for loading selected ILs on Carbon Nanofibers (CNFs) and Carbon Nanotubes (CNTs) and their extraction capability of salts from saline water.