Ni-containing catalyst for the oligomerization of olefins
The present invention relates to an oligomerization catalyst for oligomerization of low-molecular-weight olefins, to the use of said catalyst and to a process for oligomerization of low-molecular-weight olefins using the oligomerization catalyst according to the invention.
1. An oligomerization catalyst comprising:
an Al-containing binder comprising less than 0.1% by weight of Si in the total composition of the Al-containing binder,
an amorphous silica-alumina support material,
nickel oxide (NiO), and
an alkali metal or alkaline earth metal oxide;
wherein the oligomerization catalyst has a composition of:
from 15% to 40% by weight of NiO,
from 10% to 30% by weight of Al 2 O 3 ,
from 55% to 70% by weight of SiO 2 , and
from 0.01% to 2.5% by weight of the alkali metal or alkaline earth metal oxide,
wherein the oligomerization catalyst has a molar ratio of nickel ions:alkali metal/alkaline earth metal ions in the range of from 1:0.1 to 1:0.001 and is substantially free from titanium dioxide and zirconium dioxide,
wherein the oligomerization catalyst has a specific BET surface area of from 150 to 400 m 2 /g, determined by nitrogen physisorption,
wherein the oligomerization catalyst comprises mesopores and macropores, the mesopores having an average pore diameter of 5 to 15 nm, the macropores of the oligomerization catalyst having an average pore diameter of 1 to 100 μm, and
wherein the average pore volume of the mesopores and the macropores is from 0.5 to 1.45 cm 3 /g.
2. The oligomerization catalyst according to claim 1 having a molar ratio of nickel ions:aluminum ions:alkali metal/alkaline earth metal ions in the range of from 1:2:0.1 to 1:0.01:0.001, and wherein the mesopores have an average pore diameter of 7 to 14 nm, the macropores have an average pore diameter of 2 to 50 μm, and
wherein the average pore volume of the mesopores and the macropores is from 0.7 to 1.13 cm 3 /g.
3. The oligomerization catalyst according to claim 2 , wherein the oligomerization catalyst has a specific BET surface area of from 190 to 350 m 2 /g, determined by nitrogen physisorption.
4. The oligomerization catalyst according to claim 1 , wherein the alkali metal oxide or alkaline earth metal oxide is an oxide of lithium, sodium, potassium, magnesium, calcium or a mixture thereof.
5. The oligomerization catalyst according to claim 1 , wherein the oligomerization catalyst has a specific BET surface area of from 220 to 330 m 2 /g, determined by nitrogen physisorption, and wherein the mesopores have an average pore diameter of 9 to 13 nm, the macropores have an average pore diameter of 2 to 50 μm, and
wherein the average pore volume of the mesopores and the macropores is from 0.7 to 1.13 cm 3 /g.
6. The oligomerization catalyst according to claim 1 wherein the catalyst comprises from 15% to 30% by weight of NiO, from 12% to 30% by weight of Al 2 O 3 , and from 0.05% to 2% by weight of the alkali metal or alkaline earth metal oxide.
7. A process for producing the oligomerization catalyst according to claim 1 , comprising at least the steps of:
a) mixing the amorphous silica-alumina support material, the Al-containing binder, at least a portion of a nickel oxide source and at least a portion of analkali or alkaline earth oxide source; and granulating the thus-produced mixture;
a1) treating the granulate produced in step a) with at least another portion of a nickel oxide source and/or an alkali or alkaline earth oxide source,
wherein the proportion of the amorphous silica-alumina support material in the total batch (total composition including any and all employed solvents) after step a) or a1) is from 20% to 50% by weight, the proportion of the Al-containing binder in the total batch is from 5% to 30% by weight, the proportion of the alkali or alkaline earth oxide source in undissolved form in the total batch is from 0.01% to 2.5% by weight and the proportion of the nickel oxide source in the total batch is from 30% to 50% by weight; and
b) drying and calcining the granulate to produce the oligomerization catalyst.
8. The process according to claim 7 , wherein the Al-containing binder employed in step a) is an oxidic aluminum material.
9. The process according to claim 7 , wherein the amorphous silica-alumina support material employed is an amorphous aluminosilicate.
10. The process according to claim 7 , wherein the calcination in step b) is performed at a temperature between 400° C. and 800° C.
11. The process according to claim 7 , wherein the oligomerization catalyst has a final composition of from 15% to 40% by weight, of NiO, from 10% to 30% by weight of Al 2 O 3 , 55% to 70% by weight of SiO 2 and 0.01% to 2.5% by weight, of the alkali metal or alkaline earth metal oxide.
12. The process according to claim 7 wherein the oligomerization catalyst has a final composition of from 15% to 30% by weight of NiO, and from 0.05% to 2% by weight of the alkali metal or alkaline earth metal oxide.
13. The process according to claim 7 , wherein the Al-containing binder employed in step a) is selected from the group consisting of aluminum oxide, aluminum hydroxide and aluminum oxide hydroxide.
14. The process according to claim 7 , wherein the oligomerization catalyst has a final composition of from 15% to 30% by weight of NiO and 0.05% to 2% by weight of the alkali metal or alkaline earth metal oxide.
15. A process for oligomerization of C3- to C6-olefins comprising:
contacting an olefin-containing feed mixture containing the C3- to C6-olefins with a catalyst comprising the oligomerization catalyst of claim 1 in a reaction zone.
16. The process for oligomerization according to claim 15 , wherein C3- to C5-olefins are comprised in the olefin-containing feed mixture.
17. The process for oligomerization according to claim 15 , wherein C4-olefins are comprised in the olefin-containing feed mixture.
18. The process for oligomerization according to claim 15 , wherein the olefin-containing feed mixture contains less than 2% by weight of branched olefins.
19. The process for the oligomerization according to claim 15 , wherein the contacting takes place in the liquid phase.
20. The process for the oligomerization according to claim 15 , wherein the contacting is carried out at a pressure of from 10 to 70 bar and a temperature of from 50° C. to 200° C., with the proviso that if the contacting is carried out in the liquid phase the parameters pressure and temperature are chosen such that the the olefin-containing feed mixture is in the liquid phase.