Continuous prodn. of aromatic nitro:amino cpds. - using halo:nitro cpds. and aq. ammonia or lower aliphatic amine in tubular reactor with low frequency pulsation

摘要

Continuous prodn. of aromatic nitro-amino cpds. (I) from halogen-substd. nitro-aromatics (II) and 20-60, pref. 20-30% aq. NH3 soln. or lower aliphatic amines in 1:(2-20) molar excess is carried out at 140-255 deg.C and under pressure in fluid phase. The reactants are supplied to a tubular reactor with mantle for a heat exchange medium and the reaction mixt. is subjected to intensive static mixing by pulses superimposed on the flow. The reaction mixt. is discharged through a unit regulating the reactor pressure and then worked up. The novel features are as follows. Undamped low frequency lengthwise pulses with a frequency of 0.5-50 Hz and approx. the same amplitude over the entire range of action are applied to the reaction mixt.. The system pressure is greater than the sum of the partial pressure of all components present in the reactor and the reactor is kept in the isothermal state by a heat exchange medium circulating in the liquid/vapour phase transition. USE/ADVANTAGE - Mfr. costs are reduced and explosion hazards are (largely) eliminated. The quality of the reaction prod. is better than usual and the output high