Abstract
The nitration of chlorobenzene with concentrated mixed acids is a fast
and highly exothermic process,
which suffers from considerable mass transfer resistance and poor heat
transfer rates. The reaction kinetics has not been thoroughly reported
before. In this work, a continuous-flow microreactor system and a
homogeneous reaction condition were proposed to obtain accurate
chlorobenzene nitration kinetics data at high mixed acid concentrations.
A
general model for predicting the observed reaction rate constants was
established. With a new method for estimating the equilibria associated
with HNO3 in aqueous sulfuric acid, the rate constants
based on nitronium ion and activation energies were obtained. Compared
with batch reactors, the
continuous-flow microreactor system allows for a sufficient heat
transfer efficiency and accurate residence time control, making it
possible to study the reaction performance more quickly and sensitively.
This work may provide a reliable
reference for the kinetic study of similar processes.