چكيده به لاتين
Abstract: Extraction is the most common approach in order to separate sulfone compounds
from the oxidized diesel in ODS. According to economic and environmental reasons, sulfone
compounds in the extraction solvent, should be removed by an appropriate approach. In this
study, distillation and adsorption approaches have been used in order to remove oxidized
sulfur compounds from the solvent. Sulfur compounds in the initial gas oil (0551 ppmw)
were oxidized by ultrasound-assisted system in the presence of hydrogen peroxide as oxidant
and formic acid as catalyst. The oxidized gas oil was extracted by DMF, Acetonitrile, 51 – 51
vol.% solution of DMF – Acetonitrile and 51 – 51 vol.% solution of DMF – n-propanol.
DMF and Acetonitrile have the best extraction efficiency and fuel recovery, respectively.
Regeneration of used solvents by distillation has been studied in different aspects such as
regeneration efficiency in single-stage distillation, impression of double-stage distillation,
extraction ability of sulfone compounds by regenerated solvent and impression of multistage
extraction. By considering the mentioned aspects, acetonitrile and 51 – 51 vol.% solution of
DMF – Acetonitrile show better performances in consecutive processes of extraction and
regeneration. However, regenerated DMF by distillation shows weak desulfurization
efficiency in extraction stage. Thus, regeneration of DMF by adsorption approach was
studied as an alternative of distillation approach. Adsorbents such as alumina, carbon,
bentonite and TiO0 nanopowder were used to regenerate the used DMF. Carbon adsorbent
has better regeneration efficiency among the mentioned adsorbents. However, results
demonstrate that adsorption by these adsorbents couldn’t regenerate the used DMF
effectively. Finally, existed compounds in initial gas oil, oxidized gas oil, desulfurized gas oil
and removed sulfur compounds from the solvent have been studied in detail by FTIR.
Keywords: Oxidative desulfurization, extraction, recoverability, distillation, adsorption,
FTIR