Process for adiabatic preparation of mononitrohalogenbenzenes.

摘要

Prodn. of mononitro halobenzenes (I) comprises reacting the corresp. halobenzene (II) with a mixt. of HNO3, H2SO4 and H2O. The process comprises as follows: (a) the reactants are fed in any order into a reactor equipped with a mixing device, provided that: (i) the amt. of HNO3 is 1-8 wt.% and the amt of H2SO4 is 56.5-84.5 wt.% of the total amt. of HNO3, H2SO4 and H2O; (ii) the H2O is added as such and/or as a diluent for the HNO3 and/or H2SO4; and (iii) the (II):HNO3 molar ratio is 0.9-1.5:1; (b) the mixing energy is 1-40 (esp 3-30) w/l of reaction mixt.; (c) the reaction is effected under adiabatic conditions, the reactants being fed at a temp. such that mixing takes place at 60-160 degrees C and the temp. at the end of the reaction is not more than 180 degrees C; (d) the product mixt. is sepd. into an organic phase and an inorganic phase; and (e) the largely HNO3-free inorganic phase is distilled to remove H2O.