Isocyanate production procedure
AssigneeRepsol Quimica S.A.
InventorsSergio Castillon Miranda, Carmen Claver Cabrero, Elena Fernandez Gutierrez, Pilar Salagre Carnero, Marc Serra Queralt, Pedro Uriz Sola
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Abstract
The procedure consists of the catalytic thermal decomposition of a carbamate in the presence of natural or synthetic carbamates as catalysts. Isocyanates with high yields and high reaction speeds are formed selectively.
Claims42
A procedure for producing isocyanates having multiple isocyanate groups from carbamates having multiple carbamate groups by catalytic thermal decomposition, wherein natural or synthetic silicates are used as catalysts.
A process for converting a carbamate having multiple carbamate groups into an isocyanate having multiple isocyanate groups, wherein the process comprises the steps of:
- (1) providing the carbamate, wherein the carbamate has a formula I
- R1—(NHCOOR2)n (formula I)
- wherein R1 and R2 are the same or different than each other, wherein R1 and R2 are each independently an organic group selected from the group consisting of alkyl groups, alkylidene groups, alkenyl groups, allylcyclical groups, di-radical allylcyclical groups, aromatic groups, arylalkyl groups, and di-radical aromatic groups, wherein the organic group optionally contains a halogen, an alkoxy group, or a nitro group;
- and wherein n equals 2, 3, or 4;
- (2) providing a catalyst, wherein the catalyst comprises a natural or synthetic silicate;
- and
- (3) contacting the catalyst with the carbamate, wherein the isocyanate having the multiple isocyanate groups is produced by catalytic thermal decomposition.
A process for producing an isocyanate from a carbamate by catalytic thermal decomposition using a catalyst, wherein the catalyst comprises montmorillonite.
A process for converting a mixture of two carbamates into two isocyanates, wherein the process comprises the steps of:
- (1) providing a mixture of a first carbamate and a second carbamate, wherein the first carbamate and the second carbamate each independently have a formula I
- R1—(NHCOOR2)n (formula I)
- wherein R1 and R2 are the same or different than each other, wherein R1 and R2 are each independently an organic group selected from the group consisting of alkyl groups, alkylidene groups, alkenyl groups, allylcyclical groups, di-radical allylcyclical groups, aromatic groups, arylalkyl groups, and di-radical aromatic groups, wherein the organic group optionally contains a halogen, an alkoxy group, or a nitro group;
- wherein n equals 1, 2, 3, or 4;
- and wherein the first carbamate is different than the second carbamate;
- (2) providing a catalyst, wherein the catalyst comprises a natural or synthetic silicate;
- and
- (3) contacting the catalyst with the mixture of the first carbamate and the second carbamate, wherein a first isocyanate is produced from the first carbamate by catalytic thermal decomposition;
- wherein a second isocyanate is produced from the second carbamate by the catalytic thermal decomposition;
- and wherein the first isocyanate is different than the second isocyanate.
Dependencies are inferred from the claim text.