4,4'- diphenylmethane diamine , and diphenylmethane diisocyanate and polyphenylene polymethylene poly simultaneous preparation of isocyanates

摘要

The present invention is 4,4''-diphenylmethane diamine, and diphenylmethane diisocyanate and polyphenyl A method of producing a co-butylene polymethylene polyisocyanate, ; (a) by an acid condensation of aniline and formaldehyde to prepare a mixture of the diphenylmethane diamine and polymethylene polyphenylene polyamines, and then the mixture comprising: a work-up process for a, ; (b) step (a) for splitting the mixture prepared in the step part, ; (c) separating from the step (b) The mixture in the step of distillation column, ; (d) steps (c) and recycling the bottom product in the final product of step (a) of, for condensing the overhead product of step (c) step, ; (e) step (c) the overhead product from the distillation column of step, ; (f) recycling the overhead product of step (e) in the final product of step (a) that step, ; (g) step (e) in the step of separating a 4,4''-diphenylmethane diamine, which is obtained as the bottom product, ; (h) steps (a ) was reacted with phosgene in the mixture, a method comprising the reaction step of the work up process the product