Removal of catalyst residues from polypropylene

Claim 1

A PROCESS FOR THE PRODUCTION OF SOLID POLYPROPYLENE WHICH COMPRISES POLYMERIZING PROPYLENE IN AN INERT SOLVENT IN THE PRESENCE OF A COORDINATION CATALYST COMPRISING A COMPOUND OF A METAL SELECTED FROM GROUPS IV-B, V-B, VI-B, VII-B AND VIII OF THE PERIODIC TABLE AND A REDUCING AGENT TO PRODUCE IN SAID SOLVENT A SLURRY OF SOLIDPOLYPROPYLENE-CONTAINING RESIDUES OF SAID CATALYST; FORMING A MIXTURE OF SAID SLURRY WITH ANHYDROUS AMMONIA AND METHANOL; SEPARATING THE SOLID POLYPROPYLENE FROM SAID MIXTURE; CONTACTING SAID SEPARATED SOLID POLYPROPYLENE WITH METHANOL AND AN ETHANOLAMINE SELECTED FROM THE GROUP CONSISTING OF MONOETHANOLAMINE, DIETHANOLAMINE, TRIETHANOLAMINE AND MIXTURES THEREOF; AND SEPARATING THE SOLID POLYPROPYLENE FROM THE METHANOL AND TRIETHANOLAMINE MIXTURE.