Continuous production of nitrochlorobenzene, useful e.g. in pharmaceuticals or dyestuffs production, comprises nitration of chlorobenzene with a mixture of sulfuric, phosphoric and nitric acids and water, with recycling of acids

摘要

A method for the continuous production of nitrochlorobenzene by nitration of chlorobenzene with a mixture of sulfuric, phosphoric and nitric acids and water under adiabatic conditions comprises: (1) mixing the reactants at 10-80 degrees C using a phosphoric acid content of 10-50 wt%; (2) separating the products at the reactor outlet; and (3) concentrating waste acids for recycling. A method for the continuous production of nitrochlorobenzene (I) comprises: (1) feeding chlorobenzene, sulfuric acid, phosphoric acid, nitric acid and water simultaneously or in any sequence into a stirred reactor and mixing at an initial temperature of 10-80 degrees C; (2) using a mixture with a phosphoric acid content (based on all acids and water) of 10-50 wt%; (3) carrying out the reaction under adiabatic conditions; (4) separating crude (I) from the waste acids at the reactor outlet; and (5) concentrating and recycling the acids to the nitration reaction.