Claims
- 1. A process for removing Group VIII metal hydrogenation catalyst residue from a polymer, comprising:reacting a polymer cement comprising a Group VIII metal hydrogenation catalyst residue with an aqueous solution of ammonia and carbon dioxide; separating the polymer cement and Group VIII metal into phases; and recovering the polymer cement.
- 2. The process of claim 1 wherein the concentration of the ammonia in the aqueous solution is from 2 to 7% by weight and the concentration of the carbon dioxide in the aqueous solution is from 1 to 7% by weight.
- 3. The process of claim 1 wherein the concentration of the ammonia in the aqueous solution is from 3 to 6% by weight and the concentration of the carbon dioxide in the aqueous solution is from 2 to 6% by weight.
- 4. The process of claim 1, wherein the polymer cement comprises a block copolymer of styrene and a conjugated diene.
- 5. The process of claim 4, wherein the conjugated diene is butadiene or isoprene.
- 6. The process of claim 1 wherein the Group VIII metal hydrogenation catalyst residue is selected from the group consisting of iron, cobalt, nickel, and palladium.
- 7. The process of claim 1 wherein a weight ratio of the aqueous solution to the polymer cement is about 0.1 to 1.0.
- 8. A process for removing hydrogenation catalyst residue from a polymer cement, comprising:mixing an aqueous solution comprising ammonia and carbon dioxide with a polymer cement comprising hydrogenation catalyst residues; separating the aqueous solution and the polymer cement; and recovering the polymer cement.
- 9. The process of claim 8 wherein the concentration of the ammonia in the aqueous solution is from 2 to 7% by weight and the concentration of the carbon dioxide in the aqueous solution is from 1 to 7% by weight.
- 10. The process of claim 8 wherein a weight ratio of the aqueous solution to the polymer cement is about 0.1 to 1.0.
- 11. The process of claim 8 wherein the hydrogenation catalyst residue comprises a Group VIII metal selected from the group consisting of iron, cobalt, nickel, and palladium.
- 12. A process for removing Group VIII metal residue from a hydrogenated polymer cement, comprising:polymerizing a monomer selected from the group consisting of conjugated alkadienes, monoalkenyl-substituted aromatic compounds, and mixtures thereof with an alkali-metal to form a polymer cement comprising alkali metal terminated polymer; hydrogenating the polymer cement with a Group VIII metal hydrogenation catalyst to form a hydrogenated polymer cement having Group VIII metal residues; adding an aqueous solution comprising ammonia and carbon dioxide to the hydrogenated polymer cement; and recovering the hydrogenated polymer cement.
- 13. The process of claim 12, wherein the hydrogenated polymer cement comprises a block copolymer having at least two endblocks of polymerized monovinyl aromatic compound and a midblock of polymerized conjugated diene.
- 14. The process of claim 13, wherein the polymerized conjugated diene is selected from polymerized butadiene and polymerized isoprene.
- 15. The process according to claim 12, wherein the hydrogenation catalyst comprises nickel and aluminum.
- 16. The process of claim 12, wherein a weight ratio of the aqueous solution to the polymer cement is about 0.1 to 1.0.
- 17. The process of claim 12 wherein the concentration of the ammonia in the aqueous solution is from 2 to 7% by weight and the concentration of the carbon dioxide in the aqueous solution is from 1 to 7% by weight.
Parent Case Info
This application claims the benefit of U.S. Provisional Application Ser. No. 60/098,400, filed Aug. 31, 1998, the entire disclosure of which is hereby incorporated by reference
US Referenced Citations (13)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0312213 |
Apr 1989 |
EP |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/098400 |
Aug 1998 |
US |