Hydroformylation process with recycle of active rhodium catalyst
View Patent ↗The present invention relates to a continuous hydroformylation process for the production of an aldehyde by hydroformylation of an olefin which comprises: providing a hydroformylation zone containing a charge of a liquid reaction medium having dissolved therein a rhodium hydroformylation catalyst comprising rhodium in combination with carbon monoxide and a ligand; supplying the olefin to the hydroformylation zone; maintaining temperature and pressure conditions in the hydroformylation zone conducive to hydroformylation of the olefin; recovering from the liquid hydroformylation medium a hydroformylation product comprising aldehyde; recovering from the hydroformylation zone a stream comprising the rhodium catalyst; contacting at least a portion of the stream with a solid acidic absorbent under process conditions which allow at least some of the rhodium to become bound to the absorbent; subjecting the rhodium bound to the absorbent, under process conditions which allow desorption of the metal, to a fluid stripping medium comprising hydrogen and solvent; recovering the rhodium hydride catalyst; and recycling the rhodium hydride catalyst to the hydroformylation zone.
1. A continuous hydroformylation process for the production of an aldehyde by hydroformylation of an olefin which comprises:
(a) providing a hydroformylation zone containing a charge of a liquid reaction medium having dissolved therein a rhodium hydroformylation catalyst comprising rhodium in combination with carbon monoxide and a ligand;
(b) supplying the olefin to the hydroformylation zone;
(c) maintaining temperature and pressure conditions in the hydroformylation zone conducive to hydroformylation of the olefin;
(d) recovering from the liquid hydroformylation medium a hydroformylation product comprising aldehyde;
(e) recovering from the hydroformylation zone a stream comprising the rhodium catalyst;
(f) contacting at least a portion of the stream with a solid acidic absorbent under process conditions which allow at least some of the rhodium to become bound to the absorbent;
(g) subjecting the rhodium bound to the absorbent, under process conditions which allow desorption of the metal, to a fluid stripping medium comprising hydrogen and solvent;
(h) recovering the rhodium hydride catalyst; and
(i) recycling the rhodium hydride catalyst to the hydroformylation zone.
2. A process according to claim 1 wherein the stream from step (e) is divided and a first part is recycled to the hydroformylation zone and a second part is subjected to steps (f) to (i).
3. A process according to claim 2 wherein the second part is at least about 0.01% of the stream from step (e).
4. A process according to claim 1 wherein the olefin is one of more olefin selected from C 2 to C 20 olefins.
5. A process according to claim 1 wherein the olefin is not subjected to pretreatment before being charged to the hydroformylation zone.
6. A process according to claim 1 wherein the rhodium hydride catalyst is a rhodium carbonyl complex comprising rhodium in complex combination with triphenylphosphine.
7. A process according to claim 1 wherein the hydroformylation zone is operated at a temperature which will cause thermal deactivation of the catalyst.
8. A process according to claim 1 wherein the hydroformylation zone is operated at a temperature of from about 40° C. to about 180° C.
9. A process according to claim 1 wherein the feed to the hydroformylation zone includes poisons, inhibitors or poisons and inhibitors.
10. A process according to claim 9 wherein the hydroformylation zone includes at least 0.5 gram equivalent of rhodium of poisons, inhibitors or poisons and inhibitors per cubic meter of feed.
11. A process according to claim 1 wherein the feed to the hydroformylation zone includes heavies or compounds likely to form heavies in the hydroformylation zone or both.
12. A process according to claim 1 wherein the fluid stripping medium is a single fluid phase.
13. A process according to claim 12 wherein the single fluid phase is a supercritical phase.
14. A process according to claim 12 wherein the fluid stripping medium comprises two fluid phases.
15. A process according to claim 1 wherein the stream collected in step (e) contains non-volatile by-products of the reaction.
16. A process according to claim 1 wherein the stream having been contacted with the solid acidic absorbent is removed.
17. A process according to claim 1 wherein the acidic absorbent is an ion-exchange resin.
18. A process according to claim 1 wherein the acidic absorbent is a styrene divinyl copolymer containing sulphonic acid groups or carboxylic acid groups.
19. A process according to claim 1 wherein the acidic absorbent has a silica-containing backbone and an acidic functional group attached to the silica.
20. A process according to claim 19 wherein the acidic functional group is an aromatic carboxylic acid, an aliphatic carboxylic acid, an aromatic sulphonic acid or an aliphatic sulphonic acid.
21. A process according to claim 1 wherein step (g) is carried out at a temperature of from about 20° C. to about 100° C.
22. A process according to claim 21 wherein the temperature is in the region of about 50° C. to about 95° C.
23. A process according to claim 1 wherein the stream recovered in step (e) is concentrated prior to contact with the acidic absorbent.
24. A process according to claim 1 wherein the stream recovered in step (e) is diluted with a solvent compatible with the absorbent before it is contacted with the absorbent.
25. A process according to claim 1 wherein the stream recovered in step (e) is subjected to oxidation to break clustered catalyst prior to being contacted with the acidic absorbent.
26. A process according to claim 25 wherein the stream having been subjected to oxidation is treated to hydrocarbonylation.
27. A process according to claim 1 wherein the gaseous phase of the stripping medium additionally includes carbon monoxide.