Copper extraction and electrowinning result in grooves on the copper surface, accompanied by blackening.
Thread Content
Our company uses 984 extractant for extraction, and the copper sulfate solution obtained from back-extraction is used for insoluble anode electrowinning. The additive is gelatin; the Fe ion concentration is less than 42 g/l, the current density is less than 100 amps per square meter, and the temperature is around 45 degrees. The surface features grooved deposits that are not dense and not soft. The anode solution contains about 33 g/l of copper; due to the low copper content, it deposits directly on the cathode, for which stainless steel cathode plates are used. The oil content in the copper sulfate solution is <10 ppm. The anode is a lead-tin-calcium ternary alloy anode. The amount of guar gum added was 30 g/t; subsequent adjustments to this amount had little effect, with basically no improvement observed
Why isn’t anyone answering? Is it difficult? I estimate that the organic phase separation was incomplete, with organic matter present in the copper sulfate solution.
The slot numbers with high current have had their copper stripped, and there is a dark deposit on the board surface. An activated carbon filter is currently being installed, and further observation will be carried out in the future.
Is there any oil mist carried into the electrolysis section? Is an iron level of less than 42 g/L a typo? The COD can be tested again; if it’s high, that means more organic matter has been introduced.
Organic content < 10mg/L. The image below shows the surface of copper deposited under high current conditions. Iron less than 2g/L