An Overview of Structure and Dynamics Associated with Hydrophobic Deep Eutectic Solvents and Their Applications in Extraction Processes

Recent development of novel water-immiscible green solvents known as hydrophobic deep eutectic solvents (HDESs) has opened the gates for applications requiring media where the presence of water is undesirable. Ever since they were prepared, researchers have used HDESs in diverse fields such as extraction processes, CO2 sequestration, membrane formation, and catalysis. The structure and dynamics associated with the species comprising HDESs guide their suitability for specific applications. For example, varying the alkyl tail length of the HDES components significantly affects the dynamics of the components and thus helps in tuning the efficiency of extraction processes. However, the development of HDESs is still in infancy, and very few theoretical studies are available in the literature that help in understanding the structure and dynamics of HDESs. This review highlights the recent studies focused on the microscopic structure and dynamics of HDESs and their potential applications, particularly in extraction processes. We have also provided a glimpse of how the integration of experiments and computational techniques can help delineate the mechanism of extraction processes.