Supermet: Recovery of precious metals from spent catalysts by supercritical CO2 Extraction assisted by polymers

The SUPERMET project proposes to explore an eco-friendly disruptive technology for the recycling of precious metals, especially palladium (Pd) and platinum (Pt), from spent catalysts, e.g. from petrochemistry catalysts, by extraction in supercritical CO2 (scCO2) thanks to complexing polymers (cf. Figure 1). Precious metals such as Pd or Pt are used extensively in applications for catalysis not only in the petrochemistry, but also in the field of automotive and in the synthesis of fine chemicals. The scarcity of these metals poses a risk for the European countries which do not have this primary resource. The pyrometallurgical and metallurgical state of the art techniques developed for the recovery of these metals are energy-intensive, destructive, and generate large volumes of toxic effluents. The objective is to develop an extraction method which is capable to recover precious metals (e.g. Pd, Pt) from spent catalysts, generating a minimum of secondary effluents and operating in mild conditions of temperature compared to conventional routes. Within this contribution, the first results regarding the extraction of Pd are presented. In this first row of experiments, polymers with fluorinated groups, which ensure a good solubility of the polymers in scCO2, and differing complexing groups were tested regarding their extraction activity in scCO2.The SUPERMET project proposes to explore an eco-friendly disruptive technology for the recycling of precious metals, especially palladium (Pd) and platinum (Pt), from spent catalysts, e.g. from petrochemistry catalysts, by extraction in supercritical CO2 (scCO2) thanks to complexing polymers (cf. Figure 1). Precious metals such as Pd or Pt are used extensively in applications for catalysis not only in the petrochemistry, but also in the field of automotive and in the synthesis of fine chemicals. The scarcity of these metals poses a risk for the European countries which do not have this primary resource. The pyrometallurgical and metallurgical state of the art techniques developed for the recovery of these metals are energy-intensive, destructive, and generate large volumes of toxic effluents. The objective is to develop an extraction method which is capable to recover precious metals (e.g. Pd, Pt) from spent catalysts, generating a minimum of secondary effluents and operating in mild conditions of temperature compared to conventional routes. Within this contribution, the first results regarding the extraction of Pd are presented. In this first row of experiments, polymers with fluorinated groups, which ensure a good solubility of the polymers in scCO2, and differing complexing groups were tested regarding their extraction activity in scCO2.