After pre-processing the products we saw in the last video, metals can be won back by pyro- and hydrometallurgy. In this video Jan-henk Welink gives an introduction to these technologies.

Main takeaways

• After collection and preprocessing, the last stage of recovery of metals by recycling is pyro- and hydrometallurgy, in combination with electrometallurgy.
• Pyrometallurgy as a high temperature process consists in most cases of three steps: (1) feed preparation, (2) smelting, and (3) fire-refining or pyro-refining.
• Hydrometallurgical processes operate at low or near room temperature in an aqueous medium, and usually consist of four steps: (1) leaching, (2) liquid – solid separation, (3) solution purification and (4) metal precipitation.
• Hydro- or pyrometallurgy can be followed by electrometallurgy, often called electrolysis. This is a process where metallurgical reactions take place by applying an electric potential difference. It is the last step to recover metals.