Catalytic Converter Metal Recovery

As platinum group metal supplies decline, the importance of recycling catalytic converters escalates.

Catalytic converters use platinum group metals to clean auto emissions. While these rare metal resources are already endangered, demand continues to increase. Efficient recovery of catalytic converters may determine future availability of these precious metals.

Rare Metal Usage in Catalytic Converters

Manufacturing catalytic converters exhausts one-third of platinum and 87 percent of rhodium supplies. Presently, only 50 percent of these metals are being recovered because of a lack of recycling. Manufacturers are looking for ways to build products for easier recovery of these metals.

Recovery Processes

Recovering these metals involves sophisticated means of milling, then heating metals to high temperatures by adding leeching chemicals and physical processes to leech metals from the solutions. Efficient processing recovers up to 87 percent of the metals. Many recoverable metals are still lost in the milling process, however.

Recycling

Recycling of catalysts in industry use closed loop methods in which the catalysts are sent for recycling and new or refurbished catalysts are sent back to them. Such closed loop procedures are not possible with automobile catalytic converters because lifetime ownerships change. It is up to consumers to understand the dire need to recover these metals and recycle them.

References

• C&EN: Future Of Metals
• Free Patents Online: Cyanide leaching method for recovering platinum group metals from a catalytic converter catalyst