Patent ID: 8765996

Claim:
A process for preparing an isocyanate, comprising: passing a phosgene into a reactor through a first inlet of said reactor; passing an amine into said reactor through a second inlet of said reactor, thereby introducing said phosgene and said amine into a mixing zone of said reactor to mix said phosgene and said amine; and reacting said amine with said phosgene in a gas phase, optionally in the presence of at least one inert medium, to obtain an isocyanate, wherein the first inlet and the second inlet open into said mixing zone in which the phosgene and the amine are mixed to give a reaction mixture and the mixing zone is followed downstream by a diffuser in which pressure and temperature of the reaction mixture comprising said phosgene and said amine are increased, and the flow of the phosgene through the first inlet generates a reduced pressure in the second inlet and in a feed of the amine opening into the second inlet.