Process for hydroformylating short-chain olefins in the gas phase
The invention relates to a process for hydroformylating short-chain olefins, especially C2 to C5 olefins, in which the catalyst system is in heterogenized form on a support of a porous ceramic material, and to plants for performing this process.
1. A process for hydroformylating C2 to C8 olefins in a reaction zone using a heterogenized catalyst system, wherein the process is
a gaseous feed mixture containing the C2 to C8 olefins is passed together with synthesis gas over a support composed of a porous ceramic material on which the catalyst system comprising a metal from group 8 or 9 of the Periodic Table of the Elements, at least one organic phosphorus-containing ligand, a stabilizer and optionally an ionic liquid is in heterogenized form; and
the support is a block of a ceramic material, to which a washcoat composed of the same or a different ceramic material with respect to the ceramic material of the support is applied.
2. The process according to claim 1 , wherein the organic phosphorus-containing ligand in the hydroformylation catalyst system preferably has the general formula (VI)
R′-A-R″-A-R′″ (VI)
where R′, R″ and R′″ are each organic radicals, with the proviso that R′ and R′″ are not identical, and each A is a bridging —O—P(—O) 2 — group, where two of the three oxygen atoms —O— are respectively bonded to the R′ radical and the R′″ radical.
3. The process according to claim 1 , wherein the stabilizer is an organic amine compound containing at least one 2,2,6,6-tetramethylpiperidine unit of formula (I):
4. The process according to claim 1 , wherein the porous ceramic material of which the support consists is selected from the group consisting of a silicate ceramic, an oxidic ceramic, a nitridic ceramic, a carbidic ceramic, a silicidic ceramic and mixtures thereof.
5. The process according to claim 4 , wherein the silicate ceramic is selected from aluminosilicate, magnesium silicate, and mixtures thereof; the oxidic ceramic is selected from γ-alumina, α-alumina, titanium dioxide, beryllium oxide, zirconium oxide, aluminium titanate, barium titanate, zinc oxide, iron oxides (ferrites) and mixtures thereof; the nitridic ceramic is selected from silicon nitride, boron nitride, aluminium nitride and mixtures thereof; the carbidic ceramic is selected from silicon carbide, boron carbide, tungsten carbide or mixtures thereof; and the silicidic ceramic is molybdenum silicide.
6. The process according to claim 4 , wherein the porous ceramic material of which the support consists is a carbidic ceramic.
7. The process according to claim 6 , wherein the carbidic ceramic is selected from silicon carbide, boron carbide, tungsten carbide or mixtures thereof.
8. The process according to claim 1 , wherein the amount of washcoat present on the support is ≤20% by weight, based on the total amount of the support.
9. The process according to claim 1 , wherein the support composed of the ceramic material has one or more channels in main through-flow direction.
10. The process according to claim 1 , wherein the hydroformylation is conducted at a temperature in the range from 65 to 200° C.
11. The process according to claim 1 , wherein the pressure in the hydroformylation is not greater than 35 bar.
12. The process according to claim 1 , wherein the support composed of the ceramic material has one or more continuous channels in main through-flow direction.
13. The process according to claim 1 , wherein the hydroformylation is conducted at a temperature in the range from 75 to 175° C.
14. The process according to claim 1 , wherein the hydroformylation is conducted at a temperature in the range from 85 to 150° C.
15. The process according to claim 1 , wherein the pressure in the hydroformylation is not greater than 30 bar.
16. The process according to claim 1 , wherein the pressure in the hydroformylation is not greater than 25 bar.
17. The process according to claim 2 , wherein the stabilizer is an organic amine compound containing at least one 2,2,6,6-tetramethylpiperidine unit of formula (I):
18. The process according to claim 2 , wherein the porous ceramic material of which the support consists is selected from the group consisting of a silicate ceramic, an oxidic ceramic, a nitridic ceramic, a carbidic ceramic, a silicidic ceramic and mixtures thereof.
19. The process according to claim 18 , wherein the silicate ceramic is selected from aluminosilicate, magnesium silicate, and mixtures thereof; the oxidic ceramic is selected from γ-alumina, α-alumina, titanium dioxide, beryllium oxide, zirconium oxide, aluminium titanate, barium titanate, zinc oxide, iron oxides (ferrites) and mixtures thereof; the nitridic ceramic is selected from silicon nitride, boron nitride, aluminium nitride and mixtures thereof; the carbidic ceramic is selected from silicon carbide, boron carbide, tungsten carbide or mixtures thereof; and the silicidic ceramic is molybdenum silicide.
20. The process according to claim 18 , wherein the porous ceramic material of which the support consists is a carbidic ceramic.