Ionic liquids are relatively cheap, easy to synthesize, have no measurable vapor pressure and
can be competitive with conventional solvents and adopted in many industrial applications.
Hence, there is considerable interest in using them in place of volatile organic solvents for new
production technology of ultra-low sulfur petroleum fractions. According to the European Union
regulation, gasoline and diesel fuels should not exceed 10 ppm of total sulfur content starting
from 2010.
Ionic liquids 1-3 based on imidazolium cation[1-3] have been employed in an attempt to
design new functionalized liquids for solvent extraction of sulfur compounds from diesel fuel.

The highest extractive desulfurization (degree of desulfurization was 87%) was obtained with
task-specific ionic liquid 1 that exists as liquid at room temperature as mixture 2 (degree of
desulfurization was 78%). Desulfurization in the presence of metal containing ionic liquid 3 with
FeCl4
- anions and {FeIII
3O} cationic core clearly demonstrated that all the sulfur substances were
completely extracted from the diesel fuel. The procedure has remarkable practical utility because
of its simplicity and the applied functionalized ionic liquids are relatively cheap and easy to
synthesize.
We thank the bilateral BMBF project (01DK13029) for financial support and Dr. Denis Prodius
for helpful discussions.
References:
1. Prodius D., Macaev F., Stingaci E., Pogrebnoi V., Mereacre V., Novitchi G., Kostakis G.
E., Anson C. E., Powell A. K. Chem. Commun. 2013, 49, 1915.
2. Macaev F., Styngach E., Shargarovskii V., Bets L., Vlad L., Barba A. Russ. J. Org.
Chem. 2010, 46 (4), 610.
3. Sargorovschi V., Stingaci E., Macaev F. Chem. J. Moldova, 2008, 3 (2), 95.