ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 4, pp. 590!595. + Pleiades Publishing, Inc., 2006.
Original Russian Text + A. A. Gaile, V. E. Somov, G. D. Zalishchevskii, E. A. Kaifadzhyan, L. L. Koldobskaya, 2006, published in Zhurnal Prikladnoi
Khimii, 2006, Vol. 79, No. 4, pp. 599!604.
AND ION-EXCHANGE PROCESSES
Extractive Refining of Atmospheric Gas Oil
A. A. Gaile, V. E. Somov, G. D. Zalishchevskii,
E. A. Kaifadzhyan, and L. L. Koldobskaya
St. Petersburg State Technological Institute (Technical University), St. Petersburg, Russia
Kirishinefteorgsintez Production Association, Open Joint-Stock Company, Kirishi, Leningrad oblast, Russia
Received January 24, 2006
Abstract-A study was carried out of extractive refining of atmospheric gas oil with N-methylpyrrolidone
in the presence of undecane to remove aromatic hydrocarbons and sulfur-containing compounds and thus
obtain a summer diesel oil component.
Rapid growth of the number of diesel motor cars
causes the consumption and production of diesel oils
to increase. For example, in 199032006, the propor-
tion of diesel cars increased worldwide from 14 to
40350% . Within 199932004, diesel oil produc-
tion in Russia increased by 18.4%, from 46.8 to
55.4 mln tons . By contrast to car gasolines con-
sumed mostly inside Russia, diesel oils are mostly
exported: In 2004, the domestic consumption and
export were 25.8 and 29.6 mln tons, respectively .
This was paralleled by posing ever more stringent
environmental requirements on the diesel oil quality
. These requirements can be met by using hydro-
genation methods only if the end boiling point of
the feed will be decreased, so that dialkylated di-
benzothiophenes exhibiting low reactivity in hydro-
genolysis will not enter the initial diesel fraction.
However, this will decrease production of diesel oils.
Lowering of the initial boiling point of the diesel
fraction is also undesirable, as this would decrease
production of jet fuel.
When light gas oils from secondary processes (cat-
alytic and thermal cracking, coking), having an in-
creased content of aromatic hydrocarbons, are in-
volved in production of diesel and ship oils, this
decreases the quality of the resulting oil products.
The above-mentioned contradiction, namely, the
need in increasing both the production and quality
of diesel oil, can be overcome by involving into
processing atmospheric gas oil yielded in significant
amounts on AVT (atmospheric-vacuum pipe still) in-
stallations. In extractive refining of atmospheric gas
oil, dibenzothiophene derivatives and polycycloarenes,
which are the most difficult to remove in hydrorefin-
ing, should be extracted most readily. Aromatic nitro-
gen-containing components (carbazole, indole, and
quinoline homologs) poisoning hydrorefining cat-
alysts are even more easily extracted with polar sol-
Sulfur-containing compounds that partially remain
in the raffinate from extractive refining of atmospheric
gas oil are mostly saturated compounds such as di-
alkyl sulfides, thiacyclanes, and disulfides, which can
be readily cleaved in hydrorefining. Thus, it seems
possible to combine the resulting raffinate with
lightened diesel fraction and obtain high grade diesel
oil after hydrorefining of a combined flow under mild
Previously  we studied the extractive refining of
atmospheric gas oil with 2-methoxyethanol (methyl
Cellosolve) using methyl Cellosolve3water3pentane
extraction system. We confirmed a high economic ef-
ficiency of the designed process for combined produc-
tion of a diesel oil component from atmospheric gas
oil by extraction with aqueous methyl Cellosolve in
the presence of pentane, followed by hydrorefining of
the raffinate .
A drawback of the method of extractive refining
of atmospheric gas oil is that it requires fairly high
aqueous methyl Cellosolve : feed and pentane : feed
weight ratios of 5 : 1 and 1 : 1.5, respectively, which
makes the process power-consuming.