Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or absorption is effected in step (iii) by direct introduction of at least one cooling fluid, wherein the cooling fluid is introduced directly into the first gas conduit via at least one addition unit assigned to the first gas conduit.

The present invention relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture from the process for preparing isocyanate with phosgenation including sending hydrogen chloride liquid mixture into a gas-liquid separation column for separation to yield a liquid phase flow with impurities at the bottom of the gas-liquid separation column, neutralizing the liquid phase flow comprising impurities with an alkaline liquid in the neutralization tank to yield a neutralized solution, and sending the neutralized solution into a waste liquid treatment device from said neutralization tank for treatment.

The present invention relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture from the process for preparing isocyanate with phosgenation including sending hydrogen chloride liquid mixture into a gas-liquid separation column for separation to yield a liquid phase flow with impurities at the bottom of the gas-liquid separation column, neutralizing the liquid phase flow comprising impurities with an alkaline liquid in the neutralization tank to yield a neutralized solution, and sending the neutralized solution into a waste liquid treatment device from said neutralization tank for treatment.

The invention relates to a method for extracting diisocyanates that are solid at room temperature from a distillation residue, comprising the following steps: (i) providing at least one residue containing diisocyanates that are solid at room temperature, and (ii) treating the residue at a temperature of ≥120° C. to <200° C. so as to obtain diisocyanates that are solid at room temperature, the residue provided in step (i) containing ≥32 to ≤60 wt. % of bitumen and the treatment in step (ii) being carried out in at least one thin-film evaporator and/or falling-film evaporator.

The invention relates to a method for extracting diisocyanates that are solid at room temperature from a distillation residue, comprising the following steps: (i) providing at least one residue containing diisocyanates that are solid at room temperature, and (ii) treating the residue at a temperature of ≥120° C. to <200° C. so as to obtain diisocyanates that are solid at room temperature, the residue provided in step (i) containing ≥32 to ≤60 wt. % of bitumen and the treatment in step (ii) being carried out in at least one thin-film evaporator and/or falling-film evaporator.

The invention relates to a method for extracting diisocyanates that are solid at room temperature from a distillation residue, comprising the following steps: (i) providing at least one residue containing diisocyanates that are solid at room temperature, and (ii) treating the residue at a temperature of ≥120° C. to <200° C. so as to obtain diisocyanates that are solid at room temperature, the residue provided in step (i) containing ≥32 to ≤60 wt. % of bitumen and the treatment in step (ii) being carried out in at least one thin-film evaporator and/or falling-film evaporator.

The invention relates to a method for recovering a diisocyanate which is solid at room temperature from a distillation residue from a process for producing the diisocyanate, comprising the following steps: (i) mixing the distillation residue with a bitumen such that a mixture is obtained which contains 70 to 90 wt % of the distillation residue and 10 to 30 wt % of the bitumen, each in relation to the mixture, (ii) distilling the mixture in a thin-film evaporator or a falling film evaporator to obtain a sump discharge and a gaseous product stream, (iii) condensing the gaseous product stream and obtaining a solid containing the diisocyanate which is solid at room temperature. The invention further relates to the use of a thin-film evaporator or falling film evaporator, to a composition containing the diisocyanate which is solid at room temperature, and to a method for producing an elastomer from this composition and to the elastomer itself.

The invention relates to a method for recovering a diisocyanate which is solid at room temperature from a distillation residue from a process for producing the diisocyanate, comprising the following steps: (i) mixing the distillation residue with a bitumen such that a mixture is obtained which contains 70 to 90 wt % of the distillation residue and 10 to 30 wt % of the bitumen, each in relation to the mixture, (ii) distilling the mixture in a thin-film evaporator or a falling film evaporator to obtain a sump discharge and a gaseous product stream, (iii) condensing the gaseous product stream and obtaining a solid containing the diisocyanate which is solid at room temperature. The invention further relates to the use of a thin-film evaporator or falling film evaporator, to a composition containing the diisocyanate which is solid at room temperature, and to a method for producing an elastomer from this composition and to the elastomer itself.

The invention relates to a method for recovering a diisocyanate which is solid at room temperature from a distillation residue from a process for producing the diisocyanate, comprising the following steps: (i) mixing the distillation residue with a bitumen such that a mixture is obtained which contains 70 to 90 wt % of the distillation residue and 10 to 30 wt % of the bitumen, each in relation to the mixture, (ii) distilling the mixture in a thin-film evaporator or a falling film evaporator to obtain a sump discharge and a gaseous product stream, (iii) condensing the gaseous product stream and obtaining a solid containing the diisocyanate which is solid at room temperature. The invention further relates to the use of a thin-film evaporator or falling film evaporator, to a composition containing the diisocyanate which is solid at room temperature, and to a method for producing an elastomer from this composition and to the elastomer itself.

A composition is provided including a compound (A) represented by Formula (1) and a compound (B) represented by Formula (2), wherein the compound (B) is contained in an amount of 0.00002 to 0.2 parts by mass with respect to 100 parts by mass of the compound (A):

(R.sub.1—COO).sub.n—R.sub.2—(NCO).sub.m   (1)

(in Formula (1), R.sub.1 is an ethylenically unsaturated group having 2 to 7 carbon atoms; R.sub.2 is an (m+n)-valent hydrocarbon group having 1 to 7 carbon atoms; and n and m are each an integer of 1 or 2)

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(in Formula (2), R is (—R.sub.2—(OCO—R.sub.1), and R.sub.1 and R.sub.2 are the same as those in Formula (1)).