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Abstract
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Organic solvents are frequently used in the chemical industries. These solvents are used to dissolve, extract other
materials and production of products such as detergents, pesticides and many other products. Many organic
solvents are recognized as carcinogens and expensive materials. Deep eutectic solvents (DESs) are attracting
widespread technological interest as a low-cost alternative to conventional organic solvents 1 . DESs are widely
used in many fields such as dissolution and separation, electrochemistry, and materials preparation 2 . Deep
eutectic solvents are binary mixtures that have a large depression of melting temperature at the eutectic point
relative to the melting temperature of the pure components 3 . Most of the deep eutectic solvents proposed so far
are a combination of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA) at a well-defined
stoichiometric proportion. The formation of hydrogen bonding between HBA and HBD leads to the reduction
of the melting temperature of the binary m
ixtures 4 . DESs are prepared from raw materials of natural origin such
as amino acids, sugars, organic acids, alcohols and etc. 4 . Deep eutectic solvents are as diverse fields of application
of solvents such as ionic liquids (ILs). ILs are the recommended first option for eco-friendly processes within the
framework of green chemistry. ILs are considered as the best green solvents for various kinds of reaction such
as alkylation, polymerization and preextractions, etc. 5 . Probably the most important feature of ILs is its inability
the formation of a regular crystal network dut to the geometrical asymmetry of the c ations 5 . These solvents have
melting temperature falls or below ≤ 100 °C 6 . However, Compared to ILs, deep eutectic solvents have advantages
such as high thermal and chemical stability, being cheaper to make, much less toxic, and easy preparation meth-
ods. In 2003, deep eutectic solvents (DESs) based on choline chloride and urea were r
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