Short Communication
Inas M AlNashef
Abstract
Solvents play an important role in green chemistry and engineering. Availability, non-toxicity, biodegradability, recyclability, non-flammability and low price are among important factors that need to be taken into consideration when deciding whether a solvent is green or not. Up to now, the number of available green solvents is rather limited. Ionic liquids (ILs) have attracted considerable attention in many fields of scientific research. ILs have favourable characteristics, e.g. low volatility, non-flammability, thermal stability, etc. ILs have been applied in many applications including electrochemical, separation, biochemical, catalysts and many other applications. The toxicity and poor biodegradability of many ILs have been reported in the literature. ILs with high purity was also required since impurities, even in trace amounts, affect their physical properties. Additionally, their synthesis is far to be environmentally friendly. To overcome these drawbacks, a new generation of solvents, named Deep Eutectic Solvents (DES), has emerged as alternative to ILs in many applications. Formation of these DESs can be obtained by simply mixing together two or more components that can be chosen to be cheap, renewable and biodegradable. These compounds are capable of forming a eutectic mixture with a melting point lower than that of each individual component. DESs are generally liquid at temperatures lower than 100°C. Many DESs have similar physical-chemical properties to those of ILs, while being much cheaper and environmentally friendlier. In this work, author discusses and selected applications for ILs and DESs relevant to different industries, e.g. Separation, desulfurization, wastewater treatment and desalination etc.