Solvent Extraction of Copper and EDTA in Electroless Copper Plating Wastewater Using a Quaternary Ammonium Salt

To separate both copper and 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetic acid (EDTA) from the waste electroless plating solution by solvent extraction, liquid–liquid equilibria of copper-EDTA complex unbound EDTA ion were experimentally measured. An organic tri-n-octylmethylammonium chloride (TOMACl) was used as solvent. The kerosene TOMACl could extract complexes ions model wastewater. fractional removal distribution ratios decreased pH increased. valence number major or in aqueous phase increased with pH, TOMA+ cations required to chelate These had lower reactivity owing steric hindrance. effects caused a higher range, which is typical condition solution.