Separation and recovery of copper from waste printed circuit boards leach solution using solvent extraction with Acorga M5640 as extractant

Waste printed circuit boards (WPCBs) have received extensive attention in recent years because of its harmfulness and resource. In this work, two-step leaching process was carried out by using steel pickling waste liquor (SPWL) as the leaching agent. The leaching solution contains a variety of metals, especially iron, which will have an effect on the recovery of copper. Acorga M5640 (M5640) extractant with a kerosene diluent was used to recover copper from WPCBs leach solution, and the separation factor is adopted to analyze the effects of these metal ions. The effect of different parameters such as pH of aqueous phase, phase ratio (O/A), M5640 concentration, contact time as well as the concentration of H₂SO₄ as stripping reagent were investigated. Over 90.0% copper was extracted with pH 1.1, phase ratio (O/A) 1/1, M5640 concentration 16%, contact time 3 min at room temperature. For the stripping process, the 60 s contact time and 2.5 mol/L H₂SO₄ concentration are suitable with 90.0% stripping percentage of copper. Copper extraction isotherm accords with Langmuir isotherm equation and the results show that iron is the most influential metal ion for copper extraction, which will reduce the theoretical saturation of the extractant. The extractant M5640 has excellent reuse performance and can be recycled more than 10 times, which demonstrated M5640 has the industrial application value in the extraction of copper from WPCBs leach solution.