Process for preparing 3 aminomethyl-3,5,5-trimethylcyclohexylamine
Process for preparing isophoronediamine, characterized in that A) isophoronenitrile is subjected directly in one stage to aminating hydrogenation to give isophoronediamine in the presence of ammonia, hydrogen, a hydrogenation catalyst and possibly further additions, and in the presence or absence of organic solvents; or B) isophoronenitrile is first converted fully or partly in at least two or more than two stages to isophoronenitrile imine, and this isophoronenitrile imine is subjected to aminating hydrogenation to give isophoronediamine as a pure substance or in a mixture with other components and/or isophoronenitrile, in the presence of at least ammonia, hydrogen and a catalyst.
1. A process for preparing isophoronediamine, wherein
A) isophoronenitrile is subjected directly in one stage to aminating hydrogenation to give isophoronediamine in the presence of ammonia, hydrogen, a hydrogenation catalyst and possibly further additions, and in the presence or absence of organic solvents;
or
B) isophoronenitrile is first converted fully or partly in at least two or more than two stages to isophoronenitrile imine, and this isophoronenitrile imine is subjected to aminating hydrogenation to give isophoronediamine as a pure substance or in a mixture with other components and/or isophoronenitrile, in the presence of at least ammonia, hydrogen and a catalyst;
I. wherein the catalyst is a base surface activated metal alloy comprising, in its entirety, the following composition in percent by weight (% by weight), where the proportions add up to 100% by weight, based on the metals present:
cobalt: from 55% to 95% by weight
aluminum: from 5% to 45% by weight
chromium: from 0% to 3% by weight
nickel: from 0% to 7% by weight
and
II. the catalyst is in the form of granular material having particle sizes of from 1 to 8 millimeters (mm).
2. The process for preparing isophoronediamine according to claim 1 , wherein
I.
the catalyst comprises:
cobalt: from 55% to 90% by weight
aluminum: from 5% to 44.5% by weight
chromium: from 0.5% to 5% by weight.
3. The process for preparing isophoronediamine according to claim 1 , wherein
I.
the catalyst comprises:
cobalt: from 55% to 88% by weight
aluminum: from 5% to 44.5% by weight
nickel: from 0.5% to 7% by weight.
4. The process for preparing isophoronediamine according to claim 1 , wherein
I.
the catalyst comprises:
cobalt: from 55% to 85% by weight
aluminum: from 5% to 43.5% by weight
chromium: from 0.5% to 3% by weight
nickel: from 1% to 7% by weight.
5. The process for preparing isophoronediamine according to claim 1 , wherein
I.
the catalyst comprises:
cobalt: from 57% to 84% by weight
aluminum: from 10% to 40% by weight
chromium: from 1% to 2% by weight
nickel: from 2% to 4% by weight.
6. The process for preparing isophoronediamine according to claim 1 , wherein
the particle sizes of the catalyst, vary from 2.5 to 6 millimeters (mm),
or
the particle sizes of the catalyst, vary from 3 to 7 millimeters (mm),
or
the particle sizes of the catalyst, vary from 2 to 5 millimeters (mm).
7. The process for preparing isophoronediamine according to claim 4 , wherein the catalyst is obtained by screening the granules produced.
8. The process for preparing isophoronediamine according to claim 7 , wherein the catalyst is obtained by screening the granules produced, and
the particle sizes of the catalyst, have a statistical distribution
between 2.5 and 5.5 millimeters (mm), or
the particle sizes of the catalyst, have a statistical distribution between 3.5 and 6.5 millimeters (mm), or
the particle sizes of the catalyst, have a statistical distribution between 2 and 5 millimeters (mm), or
the particle sizes of the catalyst, have a statistical distribution between 3 and 7 millimeters (mm),
and where up to 10 percent of the particles may also be outside said range of said lower limit or upper limit, but up to 10 percent in each case may also be outside said range of said lower limit and upper limit.
9. The process for preparing isophoronediamine according to claim 1 , wherein the catalyst consists of, after the activation, in its entirety, the following composition in percent by weight (% by weight), where the proportions add up to 100% by weight, based on the metals present:
cobalt: from 57% to 84% by weight
aluminum: from 10% to 40% by weight
chromium: from 1% to 2% by weight
nickel: from 2% to 4% by weight
and with
particle sizes of the catalyst, having a statistical distribution between 2.5 and 5.5 millimeters (mm),
or
particle sizes of the catalyst, having a statistical distribution between 3.5 and 6.5 millimeters, (mm),
or
particle sizes of the catalyst, having a statistical distribution between 2 and 5 millimeters (mm),
or
particle sizes of the catalyst, having a statistical distribution between 3 and 7 millimeters (mm),
where up to 10 percent of the particles may also be outside said range of said lower limit or upper limit, but up to 10 percent in each case may also be outside said range of said lower limit and upper limit.
10. The process for preparing isophoronediamine according to claim 1 , wherein the catalysts additionally comprise doping metals.
11. The process for preparing isophoronediamine according to claim 1 , wherein the catalysts comprise modifiers, alkali metals and alkaline earth metals or compounds thereof, magnesium and lithium compounds.
12. The process for preparing isophoronediamine according to claim 1 , wherein at least some of the isophoronenitrile imine used is converted in the first stage by reaction with ammonia in the presence or absence of an imination catalyst and/or of solvents to isophoronenitrile imine, the conversion of IPN to IPNI after the imination being greater than 80%.
13. The process for preparing isophoronediamine according to claim 1 , wherein the first stage reaction product, as obtained or after a further treatment and/or addition of further ammonia, is subjected in the second stage to aminating hydrogenation over hydrogenation catalysts in the presence of at least ammonia and hydrogen and in the presence or absence of an organic solvent at a temperature of from 20 to 150° C., and a pressure of from 0.3 to 50 MPa.
14. The process for preparing isophoronediamine according to claim 1 , wherein the conversion of IPN to IPDA is effected in three separate reaction spaces, IPN being converted to isophoronenitrile imine with excess ammonia over imination catalysts in the first reaction space at temperatures between 20 and 150° C. and pressures between 5 and 30 MPa, the reaction products formed being hydrogenated with hydrogen in the presence of excess ammonia over hydrogenation catalysts in the second reaction space at temperatures between 20 and 130° C. and pressures of from 5 to 30 MPa, and the reaction products formed being hydrogenated over catalysts in the third reaction space at temperatures between 100 and 160° C. and pressures of from 5 to 30 MPa.
15. The process for preparing isophoronediamine according to claim 1 , wherein the imination reaction is effected in the presence of at least one imination catalyst.
16. The process for preparing isophoronediamine according to claim 1 , wherein the imination of isophoronenitrile with liquid ammonia is conducted without addition of further solvent.
17. The process for preparing isophoronediamine according to claim 1 , wherein between 1 and 500 mol, of ammonia is used per mole of IPN used in the imination stage.
18. The process for preparing isophoronediamine according to claim 1 , wherein
the imination is conducted in the presence of a suspension catalyst, of at least one fixed bed catalyst.
19. The process for preparing isophoronediamine according to claim 1 , wherein IPN and ammonia in the imination are conducted continuously from the bottom upward through a reaction tube filled with imination catalyst.
20. The process for preparing isophoronediamine according to claim 1 , wherein the hydrogen required for the hydrogenation is supplied to the reactor either in excess, or in such an amount that the hydrogen consumed by reaction and the portion of the hydrogen which leaves the reactor dissolved in the product stream is replenished.
21. The process for preparing isophoronediamine according to claim 1 , wherein the hydrogenation is conducted in liquid ammonia as solvent, using between 1 and 500 mol, of ammonia per mole of IPN.
22. The process for preparing isophoronediamine according to claim 1 , wherein the hydrogenation catalysts are first conditioned with ammonia before they are used in the hydrogenation.
23. The process for preparing isophoronediamine according to claim 1 , wherein the hydrogenation is effected continuously in fixed bed reactors.
24. The process for preparing isophoronediamine according to claim 1 , wherein the hydrogenation is conducted continuously in fixed bed reactors which are operated in trickle mode or liquid phase mode.
25. The process for preparing isophoronediamine according to claim 1 , wherein the reaction mixture leaving the hydrogenation is purified in one or more stages, and the isophoronediamine is obtained.
26. The process for preparing isophoronediamine according to claim 1 , wherein the reaction mixture leaving the hydrogenation is purified in two steps, with complete or partial removal particularly of hydrogen, inert gases, ammonia, low-boiling impurities and optionally water in one or more distillation columns in a first step, and complete or partial removal of further low-boiling impurities, water and high-boiling impurities in distillation columns in a second step, and the isophoronediamine is obtained.
27. A catalyst for preparation of isophoronediamine,
where the catalyst comprises the following properties:
I.
the catalyst consisting of, after the activation, the following composition in percent by weight (% by weight), where the proportions add up to 100% by weight, based on the metals present:
cobalt: from 55% to 95% by weight
aluminum: from 5% to 45% by weight
chromium: from 0.5% to 3% by weight
nickel: from 0.5% to 7% by weight
and
II.
the catalyst is in the form of granular material and, after the activation the catalyst is in the form of individual particles having particle sizes of from 1 to 8 millimeters (mm).