Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 1, pp. 168−170.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
S.M. Danov, V.A. Kolesnikov, A.L. Esipovich, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 1, pp. 170−171.
Kinetics of Benzene Nitration by Nitric Acid
S. M. Danov, V. A. Kolesnikov, and A. L. Esipovich
Nizhnii Novgorod State Technical University, Dzerzhinsk Division, Dzerzhinsk, Russia
Received May 12, 2009
Abstract—The kinetics of benzene mononitration in excess of 45–70 wt % nitric acid in a homogeneous liquid
phase was studied. The data on the effects of temperature and nitric acid concentration on the reaction rate were
Despite of 150-year history of the process, in industry
benzene is nitrated by a mixture of nitric and sulfuric
acids . A shortcoming of this method is the formation
of abundant waste sulfuric acid. Increasing importance
of ecologically safety technologies requires creating new
nitrating methods excluding the sulfuric acid application.
One of ways of solving this problem is the application
of only nitric acid as the nitrating agent. However as yet
the nitration of benzene by only a mixture of nitric and
sulfuric acids was widely studied [1–3].
In this work we studied the kinetics of benzene
nitration by an excess of 45–70 wt % nitric acid in
a homogeneous liquid phase in a glass temperature-
controlled batch reactor in the temperature range of
60–90°C. Typical kinetic curves of benzene consumption
are given in Fig. 1.
The obtained experimental data were treated on the
hypothesis that the rate of the benzene nitration reaction
in an excess of nitric acid is described by a ﬁ rst-order
equation with respect to benzene
r = kc
Here k is the effective rate constant of the nitration
reaction and c
, molar concentration of benzene in
a reaction mixture (M).
The linear form of the first order logarithmic
anamorphoses (Fig. 2), observed up to the deep degrees
of benzene conversion, conﬁ rms the validity of the above-
Fig. 1. Kinetic curves of benzene consumption in benzene
nitration by 56.7% nitric acid. c
is benzene concentration at the
time instant τ (M), τ, time (min). Temperature of nitration (°C):
(1) 60.1, (2) 70.5, (3) 80.1, (4) 88.1; the same for Fig. 2.
Values of rate constants (k ×105 s
) and effective activation
energies of benzene nitration in nitric acid