Removal of hydrogenation catalyst from polymer solutions by treatment with ammonia and carbon dioxide
AssigneeShell Oil Company
InventorJohn David Wilkey
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Abstract
This invention is a process comprising the steps of contacting a Group VIII metal hydrogenation catalyst residue-containing polymer solution with an aqueous solution of ammonia and carbon dioxide, separating the residue from the solution, and recovering a polymer solution preferably comprising less than 15 ppm by weight based on polymer, of the Group VIII metal. The concentration of the ammonia in the aqueous solution is from 2 to 7% by weight, preferably 3 to 6% by weight. The concentration of the carbon dioxide in the solution is from 1 to 7% by weight, preferably 2 to 6% by weight.
Claims17
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.
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.
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.
Dependencies are inferred from the claim text.