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Deep eutectic solvent
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<h2 id="natural-deep-eutectic-solvents">Natural deep eutectic solvents</h2> <p>Natural deep eutectic solvents (NADES) are bio-based<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a><a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> deep eutectic solvents which are composed of two or more compounds that are generally plant based <a href="/facts/Primary_metabolite/lqT28ncR">primary metabolites</a>, i.e. <a href="/facts/Organic_acid/2Pfb26Lp">organic acids</a>, <a href="/facts/Sugar/jb5KXRHT">sugars</a>, <a href="/facts/Alcohol_(chemistry)/Y0SCTDkh">alcohols</a>, <a href="/facts/Amine/JvfYJfP6">amines</a> and <a href="/facts/Amino_acid/WDxYwBny">amino acids</a>.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a><a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> Work done by Choi, Spronsen <i>et al</i>.<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> showed that water can be present as part of the <a href="/facts/Solvent/LoMPMz8S">solvent</a>, being strongly retained in the liquid and which cannot be <a href="/facts/Evaporation/tgvIlJys">evaporated</a>. </p> <h2 id="research">Research</h2> <p>Compared to modern <a href="/facts/Ionic_liquid/Ypse8taj">ionic liquids</a> based on discrete anions, such as <a href="/facts/Bistriflimide/mj6yj8Sc">bistriflimide</a>, which share many characteristics but are ionic compounds and not ionic mixtures, DES are cheaper to make and sometimes <a href="/facts/Biodegradation/d1UW4dfR">biodegradable</a>.<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a> Therefore, DES can be used as safe, efficient, simple, and low–cost solvents. </p><p>To date, there are numerous applications that have been studied for DES. By varying the components of the DES and their molar ratios, new DES can be produced. For this reason, many new applications are presented in the literature every year.<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> Some of the earliest applications of DES were the electrofinishing of metals using DES as electrolytes.<a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a> <a href="/facts/Organic_compound/gqCNaN45">Organic compounds</a> such as <a href="/facts/Benzoic_acid/7HrmrBYS">benzoic acid</a> (solubility 0.82 mol/L) have great solubility in DES, and this even includes <a href="/facts/Cellulose/wYPafTU0">cellulose</a>.<a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a> <a href="http://www.providespaper.eu/">[1]</a> <a href="https://web.archive.org/web/20170304035830/http://www.providespaper.eu/">Archived</a> 2017-03-04 at the <a href="/facts/Wayback_Machine/nmQ3a6JC">Wayback Machine</a> For this reason, DES were applied as extraction solvents for such material from their complex matrices. DES as extraction solvents in the separation of aromatic hydrocarbons from naphtha was also studied and promising results were published in 2012<a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a><a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a> and 2013.<a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a> </p><p>They were also studied for their applicability in the production and purification of biodiesel,<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a><a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a> and their ability to extract metals for analysis.<a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a> Incorporating microwave heating with deep eutectic solvent can efficiently increase the solubility power of DES and reduce the time required for complete dissolution of biological samples at atmospheric pressure.<a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a> It is noteworthy that proton-conducting DES (e.g. the mixture of imidazolium methanesulfonate and 1H-1,2,4-triazole in a 1:3 mole ratio or the mixture of 1,2,4-triazolium methanesulfonate and 1H-1,2,4-triazole in a 1:3 mole ratio, wherein the Brønsted base may act as the hydrogen bond donor) have also found applications as proton conductors for fuel cells.<a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a><a class="footnote-ref" id="fnref:30" href="#fn:30"><sup>30</sup></a> </p><p>Owing to their unique composition, DES are promising solvating environments, affecting the structure and self-assembly of solutes. For example, the self-assembly of <a href="/facts/Sodium_dodecyl_sulfate/H0Q2z7W3">sodium dodecyl sulfate</a> (SDS) in DES has recently been studied, implying DES can form microemulsions different from those in water.<a class="footnote-ref" id="fnref:31" href="#fn:31"><sup>31</sup></a> In another case, the solvation of the polymer <a href="/facts/Polyvinylpyrrolidone/lacTojoU">polyvinylpyrrolidone</a> (PVP) in DES is distinct from water, whereby the DES appear to be a better solvent for the polymer.<a class="footnote-ref" id="fnref:32" href="#fn:32"><sup>32</sup></a> It has been also shown that depending on <a href="/facts/State_of_matter/ojlIA1UF">state of matter</a> of the solute <a href="/facts/Homogeneous/y84KQJxl">homogeneous</a> or <a href="/facts/Heterogeneous/y84KQJxl">heterogeneous</a> mixtures are formed.<a class="footnote-ref" id="fnref:33" href="#fn:33"><sup>33</sup></a> </p><p>DES have also been studied for their potential use as more environmentally sustainable solvents for extracting gold and other precious metals from <a href="/facts/Ore/kgc9DssX">ore</a>.<a class="footnote-ref" id="fnref:34" href="#fn:34"><sup>34</sup></a> Some solvent extraction work has been done using DES solvents, Mark Foreman at <a href="/facts/Chalmers_University_of_Technology/L9PhS9LV">Chalmers</a> has in recent years published several papers on this topic. He wrote about the use of the solvents for battery recycling from an applied point of view<a class="footnote-ref" id="fnref:35" href="#fn:35"><sup>35</sup></a> and he also published what may be the first ever serious study of solvent extraction of metals from DES.<a class="footnote-ref" id="fnref:36" href="#fn:36"><sup>36</sup></a> Foreman has also published two pure research papers on the <a href="/facts/Thermodynamic_activity/kGUf85XI">activity</a> issues in DES, in the first<a class="footnote-ref" id="fnref:37" href="#fn:37"><sup>37</sup></a> he pointed out that activity coefficients in DES do appear to deviate wildly away from their values in <a href="/facts/Sodium_chloride/MWcXl3Mb">sodium chloride</a> solution while in his later paper<a class="footnote-ref" id="fnref:38" href="#fn:38"><sup>38</sup></a> he provides a mathematical model for the activity coefficients in DES using the SIT equation. Lastly, DES involvement in thermoelectrical field was researched through the incorporation of DES in thermoelectric polymer for the synthesis of improved thermoelectric polymer films.<a class="footnote-ref" id="fnref:39" href="#fn:39"><sup>39</sup></a> </p> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Smith, Emma L.; Abbott, Andrew P.; Ryder, Karl S. (12 November 2014). "Deep Eutectic Solvents (DESs) and Their Applications". Chemical Reviews. 114 (21): 11060–11082. doi:10.1021/cr300162p. hdl:2381/37428. PMID 25300631. <a href="https://doi.org/10.1021%2Fcr300162p" target="_blank">https://doi.org/10.1021%2Fcr300162p</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Smith, Emma L.; Abbott, Andrew P.; Ryder, Karl S. (12 November 2014). "Deep Eutectic Solvents (DESs) and Their Applications". Chemical Reviews. 114 (21): 11060–11082. doi:10.1021/cr300162p. hdl:2381/37428. PMID 25300631. <a href="https://doi.org/10.1021%2Fcr300162p" target="_blank">https://doi.org/10.1021%2Fcr300162p</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Gurkan, Burcu; Squire, Henry; Pentzer, Emily (19 December 2019). "Metal-Free Deep Eutectic Solvents: Preparation, Physical Properties, and Significance". The Journal of Physical Chemistry Letters. 10 (24): 7956–7964. doi:10.1021/acs.jpclett.9b01980. OSTI 1608304. PMID 31804088. S2CID 208643425. <a href="https://www.osti.gov/biblio/1608304" target="_blank">https://www.osti.gov/biblio/1608304</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"Deep Eutectic Solvents" (PDF). kuleuven.be. University of Leicester. Retrieved 17 June 2014. <a href="http://wet.kuleuven.be/english/summerschools/ionicliquids/lectures/abbott.pdf" target="_blank">http://wet.kuleuven.be/english/summerschools/ionicliquids/lectures/abbott.pdf</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Abbott, Andrew P.; Capper, Glen; Davies, David L.; Rasheed, Raymond K.; Tambyrajah, Vasuki (19 December 2003). "Novel solvent properties of choline chloride/urea mixtures". Chemical Communications (1): 70–71. doi:10.1039/b210714g. PMID 12610970. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Smith, Emma L.; Abbott, Andrew P.; Ryder, Karl S. (12 November 2014). "Deep Eutectic Solvents (DESs) and Their Applications". Chemical Reviews. 114 (21): 11060–11082. doi:10.1021/cr300162p. hdl:2381/37428. 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"Speciation, physical and electrolytic properties of eutectic mixtures based on CrCl3·6H2O and urea". Physical Chemistry Chemical Physics. 16 (19): 9047–9055. Bibcode:2014PCCP...16.9047A. doi:10.1039/c4cp00057a. hdl:2381/37718. PMID 24695874. <a href="https://figshare.com/articles/journal_contribution/10125527" target="_blank">https://figshare.com/articles/journal_contribution/10125527</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>Abbott, Andrew P.; Boothby, David; Capper, Glen; Davies, David L.; Rasheed, Raymond K. (July 2004). "Deep Eutectic Solvents Formed between Choline Chloride and Carboxylic Acids: Versatile Alternatives to Ionic Liquids". Journal of the American Chemical Society. 126 (29): 9142–9147. doi:10.1021/ja048266j. 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"Are Natural Deep Eutectic Solvents the Missing Link in Understanding Cellular Metabolism and Physiology?". Plant Physiology. 156 (4): 1701–1705. doi:10.1104/pp.111.178426. PMC 3149944. PMID 21677097. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149944" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149944</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Clarke, Coby J.; Tu, Wei-Chien; Levers, Oliver; Bröhl, Andreas; Hallett, Jason P. (24 January 2018). "Green and Sustainable Solvents in Chemical Processes". Chemical Reviews. 118 (2): 747–800. doi:10.1021/acs.chemrev.7b00571. hdl:10044/1/59694. PMID 29300087. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Svigelj, Rossella; Dossi, Nicolò; Grazioli, Cristian; Toniolo, Rosanna (January 2021). "Deep Eutectic Solvents (DESs) and Their Application in Biosensor Development". Sensors. 21 (13): 4263. Bibcode:2021Senso..21.4263S. doi:10.3390/s21134263. PMC 8271379. PMID 34206344. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271379" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271379</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> <li id="fn:20"><p>Abbott, Andrew P.; McKenzie, Katy J.; Ryder, Karl S. (2007). "Electropolishing and Electroplating of Metals Using Ionic Liquids Based on Choline Chloride". Ionic Liquids IV. ACS Symposium Series. Vol. 975. pp. 186–197. doi:10.1021/bk-2007-0975.ch013. ISBN 978-0-8412-7445-7. <a href="978-0-8412-7445-7" target="_blank">978-0-8412-7445-7</a> <a href="#fnref:20" class="footnote-back-ref">↩</a></p></li> <li id="fn:21"><p>US Patent 8022014, Richard F. Miller, "Deep eutectic solvents and applications", published 2010, issued Sep 20, 2011 <a href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US8022014" target="_blank">https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US8022014</a> <a href="#fnref:21" class="footnote-back-ref">↩</a></p></li> <li id="fn:22"><p>Kareem, Mukhtar A.; Mjalli, Farouq S.; Hashim, Mohd Ali; Hadj-Kali, Mohamed K. O.; Bagh, Fatemeh Saadat Ghareh; Alnashef, Inas M. (15 November 2012). "Phase equilibria of toluene/heptane with tetrabutylphosphonium bromide based deep eutectic solvents for the potential use in the separation of aromatics from naphtha". Fluid Phase Equilibria. 333: 47–54. doi:10.1016/j.fluid.2012.07.020. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:22" class="footnote-back-ref">↩</a></p></li> <li id="fn:23"><p>Kareem, Mukhtar A.; Mjalli, Farouq S.; Hashim, Mohd Ali; AlNashef, Inas M. (25 January 2012). "Liquid–liquid equilibria for the ternary system (phosphonium based deep eutectic solvent–benzene–hexane) at different temperatures: A new solvent introduced". Fluid Phase Equilibria. 314: 52–59. doi:10.1016/j.fluid.2011.10.024. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:23" class="footnote-back-ref">↩</a></p></li> <li id="fn:24"><p>Kareem, Mukhtar A.; Mjalli, Farouq S.; Hashim, Mohd Ali; Hadj-Kali, Mohamed K. O.; Ghareh Bagh, Fatemeh Saadat; Alnashef, Inas M. (1 October 2013). "Phase equilibria of toluene/heptane with deep eutectic solvents based on ethyltriphenylphosphonium iodide for the potential use in the separation of aromatics from naphtha". 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