Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 6, pp. 1128−1132.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
O.S. Pavlov, S.A. Karsakov, S.Yu. Pavlov, 2009, published in Khimicheskaya Promyshlennost’, 2009, Vol. 86, No. 1, pp. 71−76.
TECHNOLOGY OF ORGANIC
AND INORGANIC CHEMISTRY
The Process of Producing 2-Methyl-2-butene by Positional
Isomerization on Sulfocation Exchangers
O. S. Pavlov, S. A. Karsakov, and S. Yu. Pavlov
Yaroslavl State Technical University, Yaroslavl, Russia
e-mail: oleﬁ firstname.lastname@example.org
Scientiﬁ c and Technological Center of Chemical Technologies, Yaroslavl, Russia
Received November 14, 2008
Abstract—-The results of determination of composition and strength of the granules of nitrogen-phosphoric
fertilizers containing 1.5 to 5.0% of P
, obtained by interaction of the mineralized mass of the phosphorites of
Central Kyzylkum with the 70−90% solutions of ammonium nitrate at 110°C, are presented.
Economical producing of 2-methyl-2-butene is
an important element of the promising process of the
production of isoprene by epoxidation of 2-methyl-
2-butene and dehydration of the formed epoxide. The
effective method of the production of 2-methyl-2-
butene is dehydrogenation of isopentane and subsequent
obtaining of 2-methyl-2-butene from the formed C
fractions by liquid-phase isomerization of 2-methyl-1-
butene, preferably on sulfocation exchangers followed
by isolation of 2- methyl -2-butene from the formed C
fractions by usual rectiﬁ cation.
The proposed process makes it possible to decrease
sharply the capital investments for the reconstruction of
the existing production of isoprene from isopentane in
comparison with the OKSEP process  based on the
oxidation of isopentane.
The raw material for obtaining 2-methyl-2-butene
is the C
- fractions of the thermal or thermocatalytic
transformation of petroleum hydrocarbons, from which
the most accessible and convenient for the processing
are the fractions of the catalytic dehydrogenation of
isopentane. The process of the isopentane dehydrogenation
is achieved in the gas phase at ~600°C. It is relatively not
expensive. The conversion of isopentane, predominantly
into isopentenes, is ~ 40%. The ratio 2-methyl-1-butene :
2-methyl-2-butene : 3-methyl-1-butene in them is
approximately 1 : 1.9 : 0.15; normal boiling points of these
isobutenes are respectively 31.2°C, 38.6°C and 20.1°C.
Their separation by rectiﬁ cation does not a problem.
The transformation of the larger part of 2-methyl-1-
butene into 2-methyl-2-butene in the C
be achieved by application of a comparatively simple
method: by liquid-phase positional isomerization n the
basis of reaction (1):
This reaction proceeds sufficiently easily in the
presence of sulfocation exchanger catalyst at a temperature
from 10 to 40°C. At these temperatures the equilibrium of
reaction is strongly shifted to the side of the formation of
2-methyl-2-butene, the greater at the lower temperature.
Experimental data on he equilibrium of the reaction of
the positional isomerization of 2-methyl-1-butene into
2-methyl-2-butene are given in Table 1.
Besides the acidic (sulfocation exchanger) catalysis
for the positional isomerization of 2-methyl-1-butene into
2-methyl-2-butene can be used the catalysts containing
nickel, palladium, cobalt or platinum, in the presence
of a small quantity of hydrogen. A disadvantage of the
catalysis by this method is relatively slow conversion
and a signiﬁ cant hydrogenation of isopetenes into iso-
pentane. On the other hand, in the case of presence of