1. Recovery of Pd(II) from Hydrochloric Acid Medium by Solvent Extraction–Direct Electrodeposition Using Hydrophilic/Hydrophobic ILs
- Author
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Shunling Li, Muhan Chen, Min Shao, Ci Jin, and Zhangjie Huang
- Subjects
Chemistry ,General Chemical Engineering ,Extraction (chemistry) ,Hydrochloric acid ,General Chemistry ,C4mim ,Article ,chemistry.chemical_compound ,Ionic liquid ,Hydrophilic hydrophobic ,Solvent extraction ,QD1-999 ,Nuclear chemistry - Abstract
Mixed [C8bet]Br/[C4mim][NTf2] ionic liquids were used as a new extraction system to extract Pd(II) from multimetal-ion solutions. The separation factors KPd/M (M: Cu, Fe, Ni, Zn, Co) are greater than 103. Thiourea was found to be an effective stripping agent. After three cycles, the recovery efficiency was higher than 91.0%. Direct electrodeposition of palladium from the mixed ionic liquid phase was also studied. The Pd(II) complex in [C8bet]Br/[C4mim][NTf2] system was studied by cyclic voltammetry at 348 K. The results indicate the existence of three types of Pd(II) complex in the [C8bet]Br/[C4mim][NTf2] system, leading to three reductive waves. The reduction of Pd(II) to Pd(0) in this system is irreversible. A uniform black coating was obtained by constant-potential deposition at −1.7 V on a nickel foil, confirmed to be palladium metal by energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy analyses. After three cycles of continuous extraction–electrodeposition, over 90.0% of palladium was recovered.
- Published
- 2020