(General session) Recycling

[3401-09-08] How to separate Pt (IV) and Pd (II) with TOPO based DESs

○Lingen Guo^{1[Student presentation: Doctoral course]}, Yutaro Takaya^1,2, Chiharu Tokoro^2,1 (1. The University of Tokyo, 2. Waseda University)

司会：芳賀　一寿（秋田大学）

Keywords:selective extraction, platinum group metal separation, liquid-liquid extraction, resource and waste treatment, deep eutectic solvent

Platinum group metals (PGMs) are widely used in various industries. At the same time, due to the shortage of PGM supply, various companies, especially those using PGM-based catalysts, pay more and more attention to their recycling. One of the most difficult parts of the entire PGM recycling process is how to effectively separate Pt(IV) and Pd(II). Therefore, this paper studies how to use deep eutectic solvents (DES) based on trioctylphosphine oxide (TOPO) for separation.In previous studies, TOPO-based DES has been shown to be useful for the extraction and separation of PGM ions, but the relationship between the separation rate and the HBD structure and salt concentration in aqueous solution is unclear. Therefore, in this study, we mixed TOPO with different alcohols to prepare DESs and measured the effectiveness of different DESs in separating Pt and Pd in solutions with different salt concentrations. At the same time, in order to create a chemical environment with better separation, we also studied the physicochemical properties behind the separation, including the chemical environment of the P=O bond and how the salt concentration drives the separation.