Welcome to the Exergoecology Portal
You are here: Home / Resources / Exergoecology bibliography / A simple process for the recovery of palladium from wastes of printed circuit boards

Damien Bourgeois, Valentin Lacanau, Régis Mastretta, Christiane Contino-Pépin, and Daniel Meyer (2020)

A simple process for the recovery of palladium from wastes of printed circuit boards

Hydrometallurgy, 191.

An efficient process for the recovery of palladium from waste printed circuits boards (PCBs) is detailed. Palladium is employed as an electrode material in multi-layer ceramic capacitors (MLCCs). These components can be easily removed from PCBs by de-soldering. As palladium is alloyed with silver, its dissolution is readily achieved using dilute nitric acid. As a result, a solution containing palladium along with base metals, mostly copper and iron, is obtained. This solution is then processed through solvent extraction (SX) with a solvent based on N,N′-dimethyl,N,N′-dibutyltetradecylmalonamide (BDMA), a robust extracting molecule previously developed in the frame of the reprocessing of waste nuclear fuel. The volume of effluents generated during the SX sequence is limited: iron scrubbing is operated with a very low aqueous to organic phase volume ratio, no specific metal chelator is required for palladium stripping, and no shift from acidic to basic media is required. Finally, a ca 1 g/L Pd(II) aqueous solution with 99,4% purity is obtained, from which palladium is directly isolated as dichlorodiammine palladium(II) salt (Pd(NH3)2Cl2) after precipitation with ammonia. Overall, palladium is quantitatively recovered from the leaching solution, and no palladium was detected in the remaining solid residue. Purity is high, as no contaminating metal could be detected in the final palladium salt. The proposed approach is simple and complementary to existing hydrometallurgical processes dedicated to gold and copper recovery.

Malonamide, Palladium, Solvent extraction, e-waste

Document Actions


Please subscribe for the new newsletter.

Logo instituto Circe
Ministerio de Economía y Competitividad
Ulysea S.L. - Informática

The Material Limits of Energy Transition: Thanatia

Antonio Valero Capilla, Alicia Valero Delgado and Guiomar Calvo

This book provides a holistic view of raw mineral depletion in the context of renewable energy transistion.

The material limits Thanatia


Thanatia. Los límites minerales del planeta

mites minerales del planeta

 Antonio Valero Capilla and Alicia Valero Delgado interviewed by Adrián Almazán

We need a material transition, not only energetic, that restores nature and effectively reuses materials. Gaia must be cared for by extending life on Earth and slowing its degradation towards Thanatia.

Thanatia los limites


Thermodynamics for Sustainable Management of Natural Resources

Cover Thermodynamics

Wojciech Stanek (Editor)

This book examines ways of assessing the rational management of nonrenewable resources. Integrating numerous methods, it systematically exposes the strengths of exergy analysis in resources management.

Thanatia: The Destiny of the Earth's Mineral Resources

Cover Thanatia

A Thermodynamic Cradle-to-Cradle Assessment by (author): Antonio Valero Capilla and Alicia Valero Delgado

Is Gaia becoming Thanatia, a resource exhausted planet? For how long can our high-tech society be sustained in the light of declining mineral ore grades, heavy dependence on un-recycled critical metals and accelerated material dispersion? These are all root causes of future disruptions that need to be addressed today.