Process and catalyst for the production of pyridine and alkyl derivatives thereof
A process for increasing the overall yield of pyridine or its alkyl pyridine derivatives during a base synthesis reaction is disclosed. The process comprises reacting a C 2 to C 5 aldehyde, a C 3 to C 5 ketone or a combination thereof, with ammonia and, optionally, formaldehyde, in the gas phase and in the presence of an effective amount of a particulate catalyst comprising a zeolite, zinc, a binder, and clay and optionally a matrix, wherein the catalyst has a L/B ratio of about 1.5 to about 4.0. Preferably, the zeolite is ZSM-5. A process for enhancing the catalytic activity of a zinc and zeolite containing catalyst to increase the overall yield of pyridine and/or its derivatives during a base synthesis reaction is also disclosed.
1. A method of enhancing the catalytic activity of zinc containing zeolite-based heterogeneous catalyst for the production of pyridine and its alkyl derivatives during a base synthesis reaction, the method comprising:
(1) preparing an aqueous slurry comprising components (a) a zeolite selected the group consisting of ZSM-5, ZSM-11 and combinations thereof, (b) optionally zinc, (c) a binder and (d) clay in amounts sufficient to provide an L/B ratio of about 1.5 to about 4.0 in the final catalyst composition;
(2) spray drying the slurry to provide catalyst particles having a particle size of about 40 μm to about 200 μm;
(3) calcining the particles to provide a final catalyst composition having an L/B ratio of about 1.5 to about 4.0.
2. The method of claim 1 wherein the zeolite component in the aqueous slurry of step (1) is ZSM-5.
3. The method of claim 1 wherein the zeolite has been treated with a compound of zinc prior to incorporation into the aqueous slurry of step (1).
4. The method of claim 1 wherein a compound of zinc is incorporated as a component of the aqueous slurry of step (1).
5. The method of claim 1 comprising further ion exchanging a compound of zinc on the calcined catalyst particles.
6. The method of claim 3 wherein the compound of zinc is selected from the group consisting of nitrate, halides, acetates and combinations thereof.
7. The method of claim 4 wherein the compound of zinc is selected from the group consisting of nitrate, halides, acetates and combinations thereof.
8. The method of claim 5 wherein the compound of zinc is selected from the group consisting of nitrate, halides, acetates and combinations thereof.
9. The method of claim 1 wherein the final catalyst particles have an L/B ratio of about 2.0 to about 3.6.
10. The method of claim 1 wherein the binder is a material selected from the group consisting of aluminum sol, colloidal alumina, aluminum chlorohydrate and combinations thereof.
11. The method of claim 1 wherein the zeolite has a silica to alumina ratio of about 100 or less.
12. The method of claim 11 wherein the zeolite has a silica/alumina ratio of from about 20 to about 80.
13. The method of claim 2 wherein the zeolite has a silica/alumina ratio of about 28 to about 55.
14. The method of claim 1 wherein the shiny of step (1) further comprises a matrix material.
15. The method of claim 1 wherein the clay is kaolin clay.
16. The method of claim 1 wherein the zeolite is present in the aqueous slurry of step (1) an amount sufficient to provide from about 35 wt % to about 50 wt % zeolite based on the total weight of the final catalyst composition.
17. The method of claim 1 wherein the binder is present in the aqueous slurry of step (1) in an amount sufficient to provide from about 10 wt % to about 30 wt % binder based on the total weight of the final catalyst composition.
18. The method of claim 1 wherein the clay component is present in the aqueous slurry of step (I) in an amount sufficient to provide from about 30 wt % to about wt % clay based on the total weight of the final catalyst composition.
19. The method of claim 1 wherein the final catalyst composition has a DI of less than 20.