Extraction of Pt(IV), Pt(II), and Pd(II) from Acidic Chloride Media Using Imidazolium-Based Task-Specific Polymeric Ionic Liquid

• Published in: Industrial & engineering chemistry research Vol. 58; no. 5; pp. 1779 - 1786
• Main Authors: Xu, Zixuan, Zhao, Yonglu, Wang, Peiyu, Yan, Xinqi, Cai, Miaomiao, Yang, Ying
• Format: Journal Article
• Language: English
• Published: American Chemical Society 06-02-2019
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.8b03408

As an excellent separation material to recover platinum group metals (PGMs), imidazolium-based task-specific polymeric ionic liquid (CP-AMIN) was successfully synthesized and characterized by SEM and FT-IR. The effects of temperature, pH, reaction time, CP-AMIN amount, and concentration of chloride ion were discussed during the process of extraction of Pt­(IV), Pt­(II), and Pd­(II) from acidic chloride media. It shows high extraction efficiency under various conditions, suggesting CP-AMIN has strong adaptability of environment. CP-AMIN also presents excellent selectivity for PGMs in the solutions with coexisting metal ions (Ni2+, Mn2+, Cu2+, Cd2+, Co2+, and Cr3+), and it indicates the CP-AMIN process efficient task specificity. Notably, the acidic thiourea can desorb PGMs from CP-AMIN almost completely. After seven cycles of adsorption–desorption experiments, the extraction efficiencies still maintain above 85%. This suggests that CP-AMIN also exhibits excellent recyclability. Meanwhile, due to its being easy to handle, safe, and environmentally friendly, the task-specific polymeric ionic liquid promises great potential to recover PGMs from aqueous phase.