Search results for "Recyclability"
showing 2 items of 2 documents
A joint action of deep eutectic solvents and ultrasound to promote Diels−Alder reaction in a sustainable way
2020
The need to reduce environmental impact of chemical processes has induced a surge of attention in the choice of solvent and methodologies to carry them out. In this context, we studied the Diels−Alder reaction using N-ethylmaleimide as dienophile and changing the nature of the diene in deep eutectic solvents (DES) under both conventional heating and ultrasonic activation. DES obtained by the combination of different hydrogen bond acceptors and donors allowed assessing the role played by solvent nature. DES proved suitable solvent media for the target reaction, allowing higher yields and faster reactions compared to conventional organic solvents. The trend of yields, both in silent and under…
Selective Cobalt over Nickel separation using neat and confined ionic liquids
2020
International audience; Task Specific Ionic Liquids (TSILs) generated by association between tetraalkylammonium cations and coordinating anions such as dicyanamide (Dca-) and thiocyanate (SCN-) were used for the selective separation of Ni(II) over Co(II). SCN-based TSIL presents higher extraction efficiency than the Dca-based one towards Co(II) (E = 85.4 % vs 54.6 %) and Ni (II) (E = 22 % vs 0.5%) but lower separation factors (βCo/Ni = 21 vs 239). Interestingly, extraction of Co(II) and Ni(II) in Dca-based TSIL can be enhanced using salts with chaotropic anions such as NaNO3 (E > 90 % for Co(II) and E = 85% for Ni(II)). The use of NaCl allows, moreover, the efficient separation of both ions…