BACKGROUND
The used automobile catalytic converter is a valuable source of platinum group metals (PGMs), so it is important to have it recycled to recover precious metals as well as to meet rising industrial demand. Typically, a pyro- or hydrometallurgical method is used for the recovery of PGMs from old automobile catalytic converters. However, these methods are best suitable to recover platinum from ceramic substrate-based converters and are only partly suitable for metal substrate-based converters as they have high operating costs and low efficiency (~ 80%). All major automotive catalytic converters use metal substrates. Mechanical or chemical procedures are currently employed to recover PGMs from used metal foil-supported auto catalysts, but neither method yields optimal recovery. As a result, a novel approach for recovering PGMs from the utilized metal-foil-supported auto catalyst is needed.
SUMMARY OF TECHNOLOGY
Researchers at OSU have developed a novel mechano-chemical method for efficient and improved recovery of PGMs from used metal-foil-supported auto catalysts. This is a reliable, sustainable, and cost-effective technology for significantly improved (nearly 100%) recovery of PGMs from used metal-foil-based auto catalytic converters. This technology takes advantage of the differences in the dissolution properties of the washcoat substrate, ceramic material, and the PGMs catalyst to separate them. Combining chemical treatment with mechanical force application through ultrasonication is advantageous to maximize the extraction of PGMs quickly. A secondary effect of the proposed technology is the dissolution of the metal foil from the substrate as well; however, nearly 100% PGM dissolution is possible with minimal foil dissolution. The existing mechanical-based approach has a recovery effectiveness rate of 80%, whereas this new technology has a recovery rate of approximately 100%.
POTENTIAL AREAS OF APPLICATION
MAIN ADVANTAGES
STAGE OF DEVELOPMENT