Thioamide-Modified Pincer Extractant for Selective Pd(II) Recovery

Area of Science:

• Coordination Chemistry
• Materials Science
• Sustainable Chemistry

Background:

• Solvent extraction is crucial for recovering palladium(II) (Pd(II)) from secondary resources.
• Conventional extractants often lack efficiency and selectivity for Pd(II).

Purpose of the Study:

• Synthesize and evaluate a novel pincer extractant for enhanced Pd(II) recovery.
• Investigate the coordination behavior and extraction mechanism of the new ligand.

Main Methods:

• Synthesis of a novel pincer extractant with thioamide moieties.
• Pd(II) extraction experiments varying shaking time and HCl concentration.
• Characterization using 1H NMR, FT-IR, SCXRD, and XAS.

Main Results:

• The extractant demonstrated effective Pd(II) recovery from simulated and real-world solutions (spent automotive catalyst leach liquor).
• Distinct coordination behaviors were observed in solution (bidentate) versus crystalline state (tridentate pincer).
• Optimal conditions for extraction and stripping were identified.

Conclusions:

• The synthesized pincer extractant offers high efficiency and selectivity for Pd(II) recovery.
• Understanding the coordination modes is key for designing advanced extractants.
• This work supports the development of sustainable methods for precious metal recycling and catalyst design.