| 摘要 |
Diisocyanates production includes supplying gas flow containing diamine and phosgene to reaction zone, separating surplus phosgene and hydrogen chloride gas from gaseous reaction mixture, feeding back the separated phosgene into the reaction, and separating hydrogen chloride (15 wt.%) from the feedback phosgene stream. The mass fraction of hydrogen chloride in the phosgene-containing stream before mixing with the amine-containing stream is less than 15 wt.%. A chlorobenzene inert medium with gas volume of more than 0.0001-30 is added to the diamine- and/or phosgene-containing gas stream. Diisocyanates production includes supplying gas flow containing diamine and phosgene to reaction zone, separating surplus phosgene and hydrogen chloride gas from gaseous reaction mixture, feeding back the separated phosgene into the reaction, and separating hydrogen chloride (15 wt.%) from the feedback phosgene stream. The mass fraction of hydrogen chloride in the phosgene-containing stream before mixing with the amine-containing stream is less than 15 wt.%. A chlorobenzene inert medium with gas volume of more than 0.0001-30 is added to the diamine- and/or phosgene-containing gas stream. The reaction of the diamine with phosgene takes place in a reaction chamber (IV) at 0.1-20 bar and at 200-600[deg]C. The flow in the reaction chamber exhibits Bodenstein number of more than 10. The average contact time of the reaction mixture is 0.001-5 seconds, and the molecular ratio of phosgene to amino groups is 1.1: 1-20: 1. The isocyanate is 1,6-diisocyanatohexane, 1-isocyanato-3,3,5 tri methyl-5-(isocyanatomethyl) cyclohexane, 4,4 '-di(isocyanatocyclohexyl)methane and toluylene diisocyanate isomeric mixtures. |
