Extraction of soluble matter from polymer solids

Claim 1

A PROCESS FOR REMOVING SOLUBLE ORGANOMETALLIC CATALYSTS AND OTHER SOLUBLE MATTER FROM POLYOLEFIN SOLIDS WHICH COMPRISES CONTACTING SAID SOLIDS WITH A SOLVENT FOR SAID ORGANOMETALLIC CATALYST, SAID SOLVENT BEING ONE SELECTED FROM THE GROUP CONSISTING OF LOW MOLECULAR WEIGHT ORGANIC ACIDS, ALCOHOLS AND MIXTURES THEREOF, UNDER TURBULENT CONDITIONS IN A MIXING VESSEL WHEREBY SAID ORGANOMETALLIC CATALYST IS DISSOLVED BY SAID SOLVENT LEAVING POLYMER SOLIDS; MAINTAINING A QUIESCENT ZONE IN A LOWER EXTENSION OF SAID VESSEL SO THAT SAID POLYMER SOLIDS SETTLE THEREIN, SAID QUIESCENT ZONE HAVING A DIAMETER IN THE RANGE OF FROM 1/2 TO 1/3 THE DIAMETER OF SAID MIXING VESSEL, A HEIGHT IN THE RANGE OF FROM 3/4 TO 1 1/2 TIMES THE HEIGHTOF SAID MIXING VESSEL AND A LENGTH TO DIAMTER RATIO IN THE RANGE OF FROM 3/1 TO 7/1 WHEREBY SUFFICIENT QUIESCENCE IS MAINTAINED IN SAID ZONE TO EFFECT THE SETTLEMENT OF SAID POLYMER SOLIDS THEREIN; WITHDRAWING SETTLED POLYMER SOLIDS FROM SAID EXTENSION; COMPACTING SAID WITHDRAWN SOLIDS WHILE BACKWASHING SAME WITH FRESH SOLVENT FOR SAID OTHER SOLUBLE MATTER, SAID SOLVENT BEING FORCED INTO SAID MIXING VESSEL THROUGH SAID LOWER EXTENSION; PASSING THE COMPACTED POLYMER SOLIDS TO FURTHER RECOVERY STEPS AND WITHDRAWING SOLUTION OF SOLUBLE MATTER IN SOLVENT THROUGH AN UPWARD EXTENSION OF SAID MIXING VESSEL IN NON-TURBULENT FLOW AT A VELOCITY BELOW THE TRANSPORT VELOCITY OF SAID SOLIDS.