How do you recover precious metals from electronic waste?

Electronic waste, often referred to as e-waste, has a high recycling value. Precious metals such as gold, silver, platinum and palladium are found in various electronic components. Recovery of these precious metals not only reduces the environmental impact of e-waste, but also provides economic benefits. In this article, we will explore the techniques and equipment used to recover precious metals from e-waste.

Sorting and dismantling:

The first step in the process is the sorting and dismantling of e-waste. Advanced sorting technologies such as optical scanners and magnetic separators are utilized to separate different types of electronic components based on material composition. Dismantling is done manually or with the help of automated equipment to extract valuable components for further processing.

Crushing and Sorting:

After sorting and dismantling, e-waste is broken down into smaller pieces by mechanical processing techniques. Shredders, crushers and granulators are commonly used to reduce the size of the waste. Metals are then separated from non-metals for recycling, such as by electrostatic sorting equipment.

Chemical Leaching:

Chemical leaching is a widely adopted method of extracting precious metals from e-waste. Various leaching agents, such as acids or cyanide solutions, are used to selectively dissolve the metals. The leaching solution is then separated from the remaining waste.

Precious metal recovery:

Once the precious metals are dissolved in the leaching solution, they can be recovered using a variety of techniques:

A. Precipitation: Chemical precipitation involves the addition of suitable reagents to the leach solution so that the precious metals form insoluble compounds. These compounds can be separated by filtration or centrifugation.

b. Electrolysis: Electrolytic recovery involves passing an electric current through the leach solution, causing the precious metals to be deposited on an electrode. The electrode can be further processed to obtain pure precious metals.

C. Ion Exchange: Ion exchange resins have a high affinity for precious metals. The leaching solution is passed through a column containing the resin, which selectively absorbs the metal. The subsequent stripping process helps to recover the precious metals from the resin.

d. Smelting: Smelting is a traditional method in which the leach solution is heated to a high temperature, resulting in the separation of precious metals and the formation of a molten phase. The molten phase is then further processed to obtain pure precious metals.

Recovering precious metals from e-waste is a complex process involving a variety of technologies and equipment. Sorting, dismantling, mechanical processing, chemical leaching and subsequent recovery techniques play a vital role in extracting valuable metals from e-waste. These processes not only help mitigate the environmental impact of e-waste, but also help conserve valuable resources. If you are in need or interested, please feel free to contact us for a consultation.