The invention discloses a production process of o-
nitroaniline, and belongs to the technical field of
chemical production. According to the production process, saturated
sodium chloride brine is used as a reaction medium, o-
nitrochlorobenzene and
ammonia water are subjected to ammonolysis to prepare o-
nitroaniline, and
liquid ammonia is added in the reaction by adopting a staged
ammonia adding method to supplement
ammonia consumed in the early reaction. According to the method, while the high-concentration
saline water is used for inhibiting
side reaction, the density of a water phase is increased, the
density difference between an
oil phase and the water phase is enhanced, layering is accelerated, separation of the product o-
nitroaniline and the water phase is achieved, generation and residues of impurities are reduced, the
solubility of NH4Cl is remarkably reduced through the
common ion effect, rapid
precipitation of
ammonium chloride in the cooling layering stage is achieved, and the quality of the product is improved. Residues of
ammonium chloride in the product are reduced and the product purity is improved.
Liquid ammonia is added in the reaction, ammonia consumption is supplemented, forward proceeding of the reaction is promoted, thorough reaction is ensured,
raw material residues and
side reaction risks are reduced, and the conversion rate of o-
nitrochlorobenzene is increased.