Recovery of inert diluents used in the preparation of high molecular weight polyethylene

Claim 1

IN THE PROCESS OF POLYMERIZING ETHYLENE BY CONTACTING ETHYLENE IN AN INERT LIQUID ORGANIC DILUENT SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC, CYCLOALIPHATIC, AND AROMATIC HYDROCARBONS AND CHLORINATED ALIPHATIC AND AROMATIC HYDROCARBONS, WITH A CATALYST FORMED BY MIXING AN ORGANOMETALLIC COMPOUND OF A METAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS, ALKALINE EARTH METALS, AND EARTH METALS WITH A COMPOUND OF A METAL SELECTED FROM THE GROUP CONSISTING OF METALS OF GROUPS IV-B, V-B AND VI-B OF THE PERIODIC TABLE, THE METHOD OF RECOVERING SAID DILUENT FOR RE-USE IN THE PROCESS WHICH COMPRISES SEPARATING THE POLYMER FORMED IN THE PROCESS FROM SAID DILUENT, REACTING THE CATALYST RESIDUE IN THE DILUENT EITH OXYGEN BY INTIMATELY MIXING THE DILUENT CONTAINING SAID CATALYST RESIDUES WITH FREE OXYGEN AT A TEMPERATURE BELOW ABOUT 80* C., WHEREBY THE CATALYST RESIDUES IN SAID DILUENT ARE PRECIPITATED, SEPARATING SAID PRECIPITATED CATALYST RESIDUE, AND DRYING THE RESULTING DILUENT.