Patent ID: 6398964
Filing Date: 2002-06-04
Classification: C02F,Y10S

Abstract:
A process for treating aqueous waste comprising a copper plating waste stream, a copper rinse stream containing organic carbon and solid particles, and a copper chemical mechanical planarization (CMP) stream containing solid particles, said process comprising:electrowinning said copper plating waste stream to remove copper and create a blow down stream; filtering said rinse stream to remove solid particles; adding said blow down stream to said CMP stream; treating said blow down stream and said CMP stream with a flocculant or a coagulant to form larger solid particles; removing said larger solid particles from said CMP stream and separating the resulting liquid with an ion exchange resin in an ion exchange column wherein a liquid containing copper, a concentrated regenerant, and a dilute regenerant alternately exit said column; adding said concentrated regenerant to said waste stream before said electrowinning step; adding said dilute regenerant to said rinse stream before filtering to remove solid particles; and adding a portion of said liquid containing copper to said CMP stream during said treating step.