Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 6, pp. 926−932.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.V. Mashkina, L.N. Khairulina, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 6, pp. 945−952.
AND INDUSTRIAL ORGANIC CHEMISTRY
Catalytic Synthesis of Dimethyl Sulﬁ de
from Dimethyl Disulﬁ de and Methanol
A. V. Mashkina and L. N. Khairulina
Boreskov Institute of Catalysis, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia
Received November 22, 2011
Abstract—The reaction of dimethyl disulﬁ de with methanol was studied at atmospheric pressure and temperature
of 350°C in the presence of catalysts containing acid and basic sites.
Oxidation processes are extensively used today for re-
moving mercaptans from hydrocarbon mixtures at oil- and
gas-processing plants. These processes give a mixture of
lower dialkyl disulﬁ des dominated by dimethyl disulﬁ de
(DMDS)  suitable for synthesis of a number of valu-
able thio compounds. In this context, of particular interest
is preparation of dimethyl sulﬁ de (DMS), an important
organosulfur compound which is used for preparation
of dimethyl sulfoxide and also serves as extractant and
Solid-catalyzed conversion of DMDS in an inert me-
dium at atmospheric pressure and T = 190–350°C leads
to DMS and also to large quantities of byproducts [2–4].
Previously  we studied this reaction in the presence
of acid-base catalysts and presumed that formation of
DMS requires that the catalyst surface contain strong
acid sites and medium-strength basic sites. They cause
disruption of the S–S and C–S bonds in disulﬁ de, with the
S groups reacting to form DMS.
The appearance of the surface CH
from decomposition of DMDS is accompanied by forma-
tion of sulfur, hydrogen sulﬁ de, carbon disulﬁ de, C
hydrocarbons, and resins. As a result, DMS is produced
with a low selectivity of ≤50%. As found earlier [5, 6],
it is possible to suppress the side processes and increase
the DMS yield by introducing into the reaction system
of methanol able of more efﬁ cient, compared to DMDS,
methoxylation of the alumina surface.
Here, we studied the reaction of DMDS with methanol
in the presence of catalysts possessing different surface
acid-base properties with a view to obtaining active cata-
lysts for selective formation of DMS.
In our experiments we used chemically pure-grade
methanol and pure-grade DMDS. As support and
catalyst served off-the-shelf γ-Al
= 275 m
; also we used off-the-shelf SiO
= 310 m
as support. As catalysts served zeolites
NaX, HNaY (S
= 800 m
), HZSM-5 (Si/Al 17 and
= 500 m
), and HZSM-5 (Si/Al 17) with 20%
binder, as well as massive Cr
The supported catalysts were prepared by impregna-
tion of precalcined supports with aqueous solutions of
phosphoric, sulfuric, and tungstosilicic (HSiW) acids,
as well as chromic acid anhydride, sodium hydroxide,
ammonium tungstate, potassium tungstate, cobalt acetate,
and ammonium heptamolybdate. Bimetallic catalyst
was obtained by impregnating alumina with
an aqueous solution containing a mixture of nickel nitrate
and ammonium heptamolybdate. Catalyst CoHZSM-5
was prepared by the procedure described in .
After impregnation, all the samples were maintained in
air at room temperature for 12 h and dried at 110°C (5 h).
The samples based on phosphoric and tungstophosphoric