Modern wet copper smelting mainly refers to the leaching-extraction-electrowinning method. Extraction is the key step in modern wet copper smelting. The copper ore is treated with sulfuric acid or ammonia to obtain an acidic or alkaline leachate containing metal ions. By selecting a suitable extractant and utilizing the complexation between the extractant and metal ions, the metal ions in the aqueous phase enter the organic phase, and through further back-extraction, realized the regeneration of metal ions and the deposition of metallic copper.

Throughout the industrial process, extractants are key factors. At present, in the hydrometallurgical extraction of copper from non-ferrous metals and the regeneration and recovery of copper from etching solutions, extraction agents have been widely used, which uses the difference in distribution coefficient K between copper and impurity elements to achieve the separation of copper and impurity elements. The main chemical equation is: 2RH+Cu2+=CuR2+2H+ (RH represents the extraction agent).

The extraction agent for extracting copper from alkaline aqueous solution can use an extraction agent whose main components are β-diketone and diluent sulfonated kerosene. β-diketone is very weakly acidic and has little solubility in alkaline solutions, so it is often used in alkaline solutions or ammonia solutions to extract copper through liquid-liquid ion exchange. Moreover, β-diketone has the advantages of high selectivity and multiple reuse, so it is often used to selectively extract Cu2+ in copper hydrometallurgy and alkaline etching solution regeneration systems. Sulfonated kerosene, also known as No. 260 solvent oil, is made from sulfonated kerosene. This product is characterized by a uniform and slow evaporation rate and low aromatic hydrocarbon content. It has no odor, no residue when evaporated, and is not easily oxidized by heat. It is the most common diluent.

Copper extraction equipment often uses traditional mixing settlers. There are serious messy and environmental pollution problems in traditional copper extraction workshops, which restrict the modern development of the smelting industry. In response to these problems, Zhengzhou Tiei Extraction Technology Co., Ltd. has launched a new extraction system for copper extraction with alkaline etching liquid.

Tiei's new extraction system for extracting copper from alkaline etching liquid consists of multiple CWL-M centrifugal extraction machines and an intelligent extraction control system. Multiple centrifugal extraction machines are connected in counter-current series. The system includes the detection unit, the control unit, etc, which can basically realize unmanned operation of the flow system.
Compared with box-type tank, CWL-M type centrifugal extraction greatly improves the stirring intensity and shortens the separation time. Therefore, the mass transfer efficiency is high, the processing capacity is large, and the production efficiency is high. Under the premise of the same production volume, the amount of extraction agent is reduced, the product pressure tank is small, and the water-soluble loss of the extraction agent is significantly reduced compared with conventional methods, greatly reducing production costs.