Method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine

Abstract

The present disclosure relates to a method for preparing isophorone diamine by means of a hydrogenation reduction of isophorone nitrile imine. The hydrogenation reduction is continuously carried out in a multi-stage bubble column reactor loaded with a supported alkaline cobalt-based catalyst, wherein isophorone nitrile imine is successively in countercurrent contact with hydrogen in each stage of the reactor to carry out a hydrogenation reduction reaction, so as to obtain the isophorone diamine. The preparation method solves the problem of back-mixing, and further improves the conversion rate and the cis/trans ratio of the product.

Claims

1. A method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine, wherein the hydrogenation reduction is carried out continuously in a multistage bubble column reactor loaded with a supported alkaline cobalt-based catalyst, and isophorone nitrile imine comes sequentially in countercurrent contact with hydrogen in each stage reactor to carry out a hydrogenation reduction reaction, thereby obtaining isophorone diamine, wherein the multistage bubble column reactor includes 6 to 12 stage reactors.

2. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 1, wherein a sieve plate is used for separation between each stage reactor of the multistage bubble column reactor.

3. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 2, wherein pores on the sieve plate only enable hydrogen to pass while not allowing a reaction liquid to pass, and the reaction liquid enters the next stage reactor through a downcomer pipe and a downcomer ring.

4. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 2, wherein the supported alkaline cobalt-based catalyst is separately provided in each stage reactor, and is fixed by using the sieve plate, a pressing plate, and a dead plate; and pores of the pressing plate and the dead plate enable hydrogen and a reaction liquid to pass.

5. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 1, wherein the supported alkaline cobalt-based catalyst comprises a carrier, an active component, and an alkaline component; the carrier includes one or more of alumina, titania, zirconium dioxide, and magnesia; the active component is Co; and the alkaline component includes an oxide of Mg, Ca, Na or K.

6. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 5, wherein the active component has a mass fraction of 30% to 50%; and the alkaline component has a mass fraction of 0.1% to 5%.

7. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 1, wherein isophorone nitrile imine, when added as a reaction material, has a mass fraction of 97% or more.

8. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 1, wherein a molar ratio of hydrogen to isophorone nitrile imine during the hydrogenation reduction reaction is 5 to 100:1; and a space-time processing capacity of catalyst of the multistage bubble column reactor is 0.05 to 0.3 mol/(L*h).

9. The method for preparing isophorone diamine by means of hydrogenation reduction of isophorone nitrile imine according to claim 1, wherein a reaction temperature in the multistage bubble column reactor is 60° C. to 160° C., and the temperatures in adjacent stage reactors are the same or increase successively; and a reaction pressure in the multistage bubble column reactor is 3 to 10 MPa.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of the multistage bubble column reactor used in Example 1.

(2) 1. sieve plate; 2. catalyst; 3. downcomer pipe; 4. downcomer ring; 5. heat-exchanging coil pipe; 6. spacer ring; 7. pressing plate; 8. dead plate; A1 to A8 represent different stage reactors, respectively.

DETAILED DESCRIPTION

(3) The present disclosure will be illustrated in detail below with reference to the accompanying drawing and the specific embodiments of the specification.

EXAMPLE 1

(4) FIG. 1 showed an 8-stage continuous bubble column reactor. The column body was composed of stage reactors A1 to A8. A sieve plate 1 was used for separation between each stage reactor. The pores of the sieve plate 1 only enabled hydrogen to pass, while neither a reaction liquid nor a catalyst could pass. Each of the stage reactors A1 to A8 was loaded with a catalyst 2, and the catalyst 2 was fixed by a sieve plate 1, a pressing plate 7, and a dead plate 8. The pores of the pressing plate 7 and the dead plate 8 only enabled hydrogen and the reaction liquid to pass.

(5) A heat-exchanging coil pipe 5 was also installed on the side which was close to the outer walls of the stage reactors A1 to A8, and a heat-exchanging medium in the heat-exchanging coil pipe 5 was used for stage-wise heating. In addition, a spacer ring 6 was also installed between the sieve plate 1 and the dead plate 8. A downcomer pipe 3 and a downcomer ring 4 were also installed between the stage reactors to control the flow range of the reaction liquid.

(6) In the continuous bubble column reactor as described above, the volume of the catalyst in each stage reactor was 1 L, and the continuous bubble column reactor was loaded with a supported alkaline cobalt-based catalyst, in which the content of cobalt was 40%, the content of sodium oxide was 2%, and the carrier was alumina. Thereafter, an IPNI solution in which IPNI was the reactant having a content of 98.6% (except for the solvent) was added at 0.4 mol/h via a metering pump from the top of the bubble column, while hydrogen was consecutively introduced at 4 mol/h from the bottom. The space-time processing capacity of catalyst corresponding to this operating condition was 0.05 mol/(L*h), and the molar ratio of hydrogen to IPNI was 10. Hot oils with different temperatures were respectively introduced into the heat-exchanging coil pipes of A1 to A8, the temperatures of the stage reactors were respectively controlled at 60° C., 60° C., 70° C., 70° C., 80° C., 90° C., 100° C., and 110° C. from top to bottom, and the pressure was controlled at 3 MPa. The reaction product was collected from the bottom.

(7) After the system was operated stably for 100 hours, the product was sampled and analyzed. The sampling analysis indicated that, in addition to ammonia and water, the reaction output contained the product IPDA with a content of 98.52% and the following main by-products according to the gas chromatography analysis. Among said main by-products, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TAO) was 0.53%, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]oct-7-ylideneamine (amidine) was 0.41%, and the content of 3-aminomethyl-3,5,5-trimethylcyclohexanol (IPAA) was 0.26%. The selectivity for IPDA was 98.5%, and the cis/trans isomer ratio was 83/17.

EXAMPLE 2

(8) An 8-stage bubble column reactor as shown in FIG. 1 was used, and was loaded with a supported alkaline cobalt-based catalyst, in which the content of cobalt was 50%, the content of magnesium oxide was 5%, and the carrier was titanium dioxide. Thereafter, an IPNI solution in which IPNI was the reactant having a content of 97.2% (except for the solvent) was added at 2.4 mol/h via a metering pump from the top of the bubble column, while hydrogen was consecutively introduced at 240 mol/h from the bottom. The space-time processing capacity of catalyst corresponding to this operating condition was 0.3 mol/(L*h), and the molar ratio of hydrogen to IPNI was 100. Hot oils with different temperatures were respectively introduced into the heat-exchanging coil pipes of A1 to A8, the temperatures of the stage reactors were respectively controlled at 80° C., 80° C., 90° C., 90° C. 100° C., 120° C., 140° C., and 160° C. from top to bottom, and the pressure was controlled at 10 MPa. The reaction product was collected from the bottom.

(9) After the system was operated stably for 60 hours, the product was sampled and analyzed. The sampling analysis indicated that, in addition to ammonia and water, the reaction output contained the product IPDA with a content of 98.31% and the following main by-products according to the gas chromatography analysis. Among said main by-products, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TAO) was 0.62%, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]oct-7-ylideneamine (amidine) was 0.45%, and the content of 3-aminomethyl-3,5,5-trimethylcyclohexanol (IPAA) was 0.28%. The selectivity for IPDA was 98.3%, and the cis/trans isomer ratio was 79/21.

EXAMPLE 3

(10) An 8-stage bubble column reactor as shown in FIG. 1 was used, and was loaded with a supported alkaline cobalt-based catalyst, in which the content of cobalt was 30%, the content of potassium oxide was 0.1%, and the carrier was magnesium oxide. Thereafter, an IPNI solution in which IPNI was the reactant having a content of 98.2% (except for the solvent) was added at 1.2 mol/h via a metering pump from the top of the bubble column, while hydrogen was consecutively introduced at 24 mol/h from the bottom. The space-time processing capacity of catalyst corresponding to this operating condition was 0.15 mol/(L*h), and the molar ratio of hydrogen to IPNI was 20. Hot oils with different temperatures were respectively introduced into the heat-exchanging coil pipes of A1 to A8, the temperatures of the stage reactors were respectively controlled at 70° C., 70° C., 80° C., 90° C. 100° C., 110° C., 120° C. and 130° C. from top to bottom, and the pressure was controlled at 6 MPa. The reaction product was collected from the bottom.

(11) After the system was operated stably for 80 hours, the product was sampled and analyzed. The sampling analysis indicated that, in addition to ammonia and water, the reaction output contained the product IPDA with a content of 98.42% and the following main by-products according to the gas chromatography analysis. Among said main by-products, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TAO) was 0.57%, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]oct-7-ylideneamine (amidine) was 0.40%, and the content of 3-aminomethyl-3,5,5-trimethylcyclohexanol (IPAA) was 0.27%. The selectivity for IPDA was 98.4%, and the cis/trans isomer ratio was 81/19.

EXAMPLE 4

(12) An 8-stage bubble column reactor as shown in FIG. 1 was used, in which the number of stages was changed to 6, and the bubble column reactor was loaded with a supported alkaline cobalt-based catalyst, in which the content of cobalt was 30%, the content of potassium oxide was 0.1%, and the carrier was magnesium oxide. Thereafter, an IPNI solution in which IPNI was the reactant having a content of 98.2% (except for the solvent) was added at 0.9 mol/h via a metering pump from the top of the bubble column, while hydrogen was consecutively introduced at 27 mol/h from the bottom. The space-time processing capacity of catalyst corresponding to this operating condition was 0.15 mol/(L*h), and the molar ratio of hydrogen to IPNI was 30. Hot oils with different temperatures were respectively introduced into the heat-exchanging coil pipes of A1 to A6, the temperatures of the stage reactors were respectively controlled at 80° C., 90° C., 100° C., 110° C., 120° C. and 130° C. from top to bottom, and the pressure was controlled at 6 MPa. The reaction product was collected from the bottom.

(13) After the system was operated stably for 70 hours, the product was sampled and analyzed. The sampling analysis indicated that, in addition to ammonia and water, the reaction output contained the product IPDA with a content of 98.13% and the following main by-products according to the gas chromatography analysis. Among said main by-products, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TAO) was 0.59%, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]oct-7-ylideneamine (amidine) was 0.46%, and the content of 3-aminomethyl-3,5,5-trimethylcyclohexanol (IPAA) was 0.31%. The selectivity for IPDA was 98.1%, and the cis/trans isomer ratio was 80/20.

EXAMPLE 5

(14) An 8-stage bubble column reactor as shown in FIG. 1 was used, in which the number of stages was changed to 12, and the bubble column reactor was loaded with a supported alkaline cobalt-based catalyst, in which the content of cobalt was 40%, the content of calcium oxide was 2%, and the carrier was zirconium dioxide. Thereafter, an IPNI solution in which IPNI was the reactant having a content of 98.2% (except for the solvent) was added at 2.4 mol/h via a metering pump from the top of the bubble column, while hydrogen was consecutively introduced at 120 mol/h from the bottom. The space-time processing capacity of catalyst corresponding to this operating condition was 0.2 mol/(L*h), and the molar ratio of hydrogen to IPNI was 50. Hot oils with different temperatures were respectively introduced into the heat-exchanging coil pipes of A1 to A12, the temperatures of the stage reactors were respectively controlled at 70° C., 70° C., 80° C., 80° C., 90° C., 90° C., 100° C., 100° C., 110° C., 110° C., 120° C. and 120° C. from top to bottom, and the pressure was controlled at 8 MPa. The reaction product was collected from the bottom.

(15) After the system was operated stably for 80 hours, the product was sampled and analyzed. The sampling analysis indicated that, in addition to ammonia and water, the reaction output contained the product IPDA with a content of 98.69% and the following main by-products according to the gas chromatography analysis. Among said main by-products, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TAO) was 0.49%, the content of 1,3,3-trimethyl-6-azabicyclo[3.2.1]oct-7-ylideneamine (amidine) was 0.36%, and the content of 3-aminomethyl-3,5,5-trimethylcyclohexanol (IPAA) was 0.25%. The selectivity for IPDA was 98.7%, and the cis/trans isomer ratio was 82/18.