Excess Etchant Reduction and Copper Recovery Process for Cupric Chloride Recovery

EPA Contract Number: 68D98143
Title: Excess Etchant Reduction and Copper Recovery Process for Cupric Chloride Recovery
Investigators: Oxley, James E.
Small Business: Oxley Research Inc.
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: September 1, 1998 through March 1, 1999
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (1998) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , SBIR - Waste , Small Business Innovation Research (SBIR)


Approximately 15 million gallons of excess acid cupric chloride etchant are generated each year and this amount is growing 12-15% annually. This project concerns an innovative, electrolytic, recovery process that reduces excess etchant generation by 53% for acid cupric chloride etchers who use chemical regeneration. It is targeted particularly at printed circuit (PC) board and leadframe etchers who employ chemical regeneration and require an etchant purge to hold down impurities like photoresist organics from PC boards, and the 4% nickel in popular leadframe alloy 7025, respectively. Even the simplest process version captures 91% of the copper etched as high-value plate, while reducing makeup HCl required for regeneration by 57%. Incorporating electrodialysis into the process lowers makeup HCl even more. Key to process success is recent availability of novel proton-selective membranes, which would separate anode and cathode compartments in recovery cells. Being selectively permeable to protons, the membranes do not pass other ionic species at an appreciable rate. Non-ionic species, the most important being water, are similarly prevented from cross-over. The overall objective of this Phase I project is to demonstrate feasibility of this process applied to both PC board fabrication and leadframe etching.

Supplemental Keywords:

small business, SBIR, hazardous/solid waste, pollution prevention, engineering, chemistry, EPA., Scientific Discipline, Toxics, Waste, Sustainable Industry/Business, National Recommended Water Quality, Chemical Engineering, cleaner production/pollution prevention, Chemistry, Technology for Sustainable Environment, New/Innovative technologies, Hazardous, cleaner production, chemical use efficiency, printed circuit boards, electrochemical techniques, industrial process, production processes, copper, electrochemical, innovative technology, integrated energy, environment, and manufacturing method, cadmium, innovative technologies, pollution prevention, source reduction

Progress and Final Reports:

  • Final Report