Direct extraction of platinum nanoparticles from fuel cells with ionic liquids: Part 1. Implementation and optimization of the process parameters - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Accéder directement au contenu
Article Dans Une Revue Industrial and engineering chemistry research Année : 2023

Direct extraction of platinum nanoparticles from fuel cells with ionic liquids: Part 1. Implementation and optimization of the process parameters

Résumé

The cost of proton-exchange membrane fuel cell (PEMFCs) comes mainly from the platinum nanoparticles, which are used as catalyst; it represents 40 % of the stack price for a large-scale production. It is thus crucial to reduce their cost to produce cheaper devices, which could compete with fossil energy on the industrial market. One way to reach this goal would be to recover the Pt catalyst from the membrane electrode assembly (MEA) for further recycling. For now, current end-of-life (EoL) technologies are mainly based on hydrometallurgical and pyro-hydrometallurgical processes for recovering platinum which are identified to be energy demanding generate high amounts of toxic liquids and gaseous effluents. To meet sustainability and circular economy criteria in the recycling of noble metals, our approach was based on the use of ionic liquids (ILs) to both extract and stabilize platinum in the form of metallic nanoparticles (Pt NPs), thus avoiding the emissions of hydrofluoric acid (HF) and the use of strong acids, which make the waste management of conventional processes complicated. Thirteen different ILs were selected to investigate how their structural composition as well as their physico-chemical properties may affect the extent of Pt extraction, and their ability to stabilize detached nanoparticles. This screening study showed that ionic liquids could interact with all the elements of the active layer and allowed us to delineate the key parameters that ILs should possess to achieve the best extraction performance: hydrophilicity, the hydrogen bonding ability, the coordinating ability of the anions. The best result was obtained with the trihexyltetradecylphosphonium chloride (P66614Cl) (commercial Cyphos® IL 101) (120 °C and 6 h) which not only led to an extraction extent up to > 90 % of the Pt present initially on the catalytic layer, but also allowed in a single step to detach the Pt NPs from the carbon support. The metallic Pt NPs suspended in P66614Cl were found stable with diameter around 2-3 nm as evidenced by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) analyses. Compared to conventional processes, this safer and convenient route to recover Pt catalyst from MEAs directly in their metallic form by simple immersion of the electrode in the appropriate IL opens up new perspectives in term of rare earth metal recycling from material composites.

Domaines

Chimie
Fichier principal
Vignette du fichier
Final revised manuscript.pdf (1.68 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

cea-04130881 , version 1 (16-06-2023)

Identifiants

Citer

Mathias Coudray, Emmanuel Billy, Hakima Mendil-Jakani, Paul Haumesser, Catherine C Santini, et al.. Direct extraction of platinum nanoparticles from fuel cells with ionic liquids: Part 1. Implementation and optimization of the process parameters. Industrial and engineering chemistry research, 2023, 62 (16), pp.6355−6366. ⟨10.1021/acs.iecr.2c04523⟩. ⟨cea-04130881⟩
77 Consultations
27 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More