638
TUZHIKOV et al.
of hexane and acetone as eluent). Published data [18]:
pump into the upper part of the column in an amount of
1.2 l h . The reaction temperature was maintained in the
bp 180°C, n D2 0 1.4924, d 1.064 g cm .
20
–3
–1
4
–
1
range 25–35°C by passing cold water through the jacket.
Unreacted substances were condensed in the reflux
condenser and returned into the reactor. The exhaust
gases were delivered into a Tishchenko flask filled with
a solid alkali, to be absorbed there. The reaction product
was collected in the still of the column. The reaction
course was monitored by the difference between the
readings of rotameters at the reactor inlet and outlet,
as well as by the amount of the resulting liquid phase
and its composition, determined by chromatography.
The reaction product was a colorless fluid. We obtained
IR spectrum, ν, cm : 1325 (CH –), 2850 (–CH –),
3
2
1
2
(
962 (CH –S–), 3420 (–OH). H NMR spectrum
3
DMFA-d ), δ, ppm: 2.09 s (CH –), 2.63 t (–CH –S–,
6 3 2
J = 6 Hz), 3.90 t (HO–CH –, J = 6 Hz), 4.78 m
HO–CH –). Found (%): C 39.10, H 8.75, S 34.79.
C H OS. Calculated (%): C 39.02, H 8.52, S 34.23.
2
(
2
3
8
The results of the study are presented in Table 1 and
Fig. 1.
Reaction of ethylene oxide with methyl mercaptan
in the bubble column. The synthesis reactor had the
form of a glass column with a diameter of 15 mm and
height of 250 mm, equipped with a jacket and a reflux
condenser. The lower part of the column, with a sealed-
in porous plate, was charged to a height of 135 mm
with methyl(β-oxyethyl) sulfide containing 0.05 wt %
potassium hydroxide.The reactor temperature was raised
to 30°C by delivering warm water into the jacket. The
starting reagents, ethylene oxide and methyl mercaptan,
were batched from cylinders into the lower part of the
reactor at a rate of 16.8 l h . The catalyst, 10% solution
of potassium hydroxide in methyl(β-oxyethyl) sulfide,
was delivered with a syringe-type metering device at
a rate of 0.35 g h–1. After the temperature of 40°C was
reached, cold water was delivered into the jacket to
maintain the reactor temperature at 30–40°C. Unreacted
gases were transferred through the reflux condenser into
a Tishchenko flask filled with an alkali, to be absorbed
there. The process was monitored by readings of
rotameters at the reactor inlet and outlet, and also by the
amount and composition of the resulting reaction mass,
which was analyzed by chromatography. The reaction
product was a colorless fluid. We obtained 136.8 g of
raw methyl(β-oxyethyl) sulfide (yield 99%), with the
2
36.8 g of raw methyl(β-oxyethyl) sulfide (yield 96%,
2
0
content of the main substance 97.7%, n
1.4918,
D
2
0
–3
d 1.061 g cm ).
4
Table 3 lists the results of our study of the reaction
between ethylene oxide and methyl mercaptan in the
packed column.
Isolation of methyl(β-oxyethyl) sulfide. To remove
low-boiling by-products from raw methyl(β-oxyethyl)
sulfide, we placed 200 g of raw methyl(β-oxyethyl)
sulfide in a distillation flask and kept the flask at 58–
–
1
6
0°C and a residual pressure of 200 mm Hg for 2 h.
The weight of the residue, technical-grade methyl-
β-oxyethyl) sulfide, was 197.2 g (yield 98.6%). The
(
content of the main substance was no less than 99.0%.
Then the residue was distilled at 80–82°C and a residual
pressure of 32 mm Hg. We obtained 158.7 g of methyl(β-
2
0
20
–3
oxyethyl) sulfide (80.5%), nD 1.4924, d 1.064 g cm .
4
CONCLUSIONS
(1) It was demonstrated that the reaction of ethylene
oxide with methyl mercaptan in the presence of
potassium hydroxide enables synthesis of methyl-
(β-oxyethyl) sulfide in 98–99% yield.
2
0
content of the main substance being 97.4% (n 1.4922,
D
20
–3
d 1.062 g cm ).
4
Table 2 lists the results of our study of the reaction
between ethylene oxide and methyl mercaptan in the
bubble column.
(2) The process in which methyl(β-oxyethyl) sulfide
is synthesized in bubble and packed columns was
optimized. The mathematical experiment design method
was employed to determine the optimal parameters with
which the reaction can be performed under atmospheric
pressure in comparatively mild conditions to give
a technical-grade product with the content of the main
substance no less than 99%.
Reaction of ethylene oxide with methyl mercaptan
in the packed column. Ethylene oxide and methyl
mercaptan were delivered at a rate of 30 l h–1 into the
lower part of the packed column with a diameter of
2
8
0 mm, height of 350 mm, and packing bed height of
0 mm, equipped with a jacket and a reflux condenser.
(3) It was shown that synthesis in a bubble column
is more technologically convenient than that in a packed
column because of the unnecessary sprinkling. At the
Methyl(β-oxyethyl) sulfide containing 0.05 wt %
potassium hydroxide was delivered with a batching
RUSSIAN JOURNAL OF APPLIED CHEMISTRY Vol. 84 No. 4 2011