Platinum group metal (PGM) recovery involves the extraction, purification, and recycling of metals such as platinum, palladium, rhodium, iridium, osmium, and ruthenium. These metals are valuable and used in various industries, including automotive, jewelry, electronics, and catalytic converters. The recovery process typically includes the following steps:
1. Collection and Sorting:
PGM-containing materials are collected from various sources, such as used catalytic converters, electronic waste, mining ores, or industrial byproducts.
2. Crushing and Grinding:
The collected materials are crushed and ground into smaller particles to facilitate further processing.
3. Chemical Leaching or Dissolution:
Smelting: In some cases, materials are smelted to separate and melt out the PGMs from other metals.
Chemical Leaching: For other materials, acids or cyanide solutions are used to dissolve the PGMs from the materials.
4. Solvent Extraction:
The solution containing dissolved PGMs is treated with solvents or other chemical agents to selectively extract and concentrate the PGMs from the solution.
5. Precipitation and Refining:
Chemical reactions are induced to precipitate the PGMs from the solution in the form of solid compounds.
The solid compounds are further processed and refined to obtain pure metallic PGMs.
6. Melting and Alloying:
The recovered PGMs are melted and often alloyed with other metals to create specific alloys for various applications.
7. Forming and Shaping:
The pure PGMs or PGM alloys are shaped into various forms, such as bars, ingots, sheets, or wires, depending on their intended use.
8. Quality Control and Testing:
The recovered PGMs undergo rigorous quality control measures and testing to ensure purity, strength, and specific characteristics are met.
9. Environmental Considerations:
The recovery process adheres to environmental standards and ensures proper waste management to minimize environmental impact.
PGM recovery is a complex process involving various chemical and metallurgical steps to extract, purify, and refine these valuable metals for reuse in different industries. The process contributes to the conservation of resources and the reduction of the need for new mining activities.