Patent ID: 7118653

Claim:
A process for the production of toluenediisocyanate comprising the steps of: a) reacting toluene diamine with phosgene resulting in a crude distillation feed, b) separating the phosgene from the crude distillation feed from step a) when the crude distillation feed from step a) comprises 2% by weight or more of phosgene, resulting in a crude distillation feed comprising less than 2% by weight phosgene, c) separating the crude distillation feed comprising toluene-diisocyanate, an organic solvent and less than 2% by weight phosgene in a dividing-wall distillation column into at least four product fractions P 1 –P 4 , whereby P 1 is a phosgene enriched low-boiler product, P 2 is a solvent-enriched product, P 3 is a high boiler enriched bottoms and P 4 is a toluenediisocyanate product stream.