Abstract
Adsorption behavior of Pd(II) chloride complexes using pyridine series ionic liquid (BPHFP) was investigated to establish a clean Pd(II) recovered process by use of ionic liquids as an adsorvent. Adsorption amount of Pd(II) to BPHFP reached a maximum under a low HCl concentration. This is a similar result using a traditional ion–exchange resin, however, no Langmuir adsorption behavior was confirmed in the case of Pd(II) concentration of 1–50 mmol⁄dm3. PdCl2 exists as a soluble monomeric PdCl42− species in higher HCl concentration solution. On the other hand, an insoluble polymeric Pd species is generated in the solution of low HCl concentration. These results indicaled that Pd(II) adsorption using BPHFP was controlled by chemisorption, and the direct coordination of Pd(II) onto pyridine was possibly occurred. Moreover, inorganic support–BPHFP composite material (ILISP) was also developed. The ILISP showed an availability as a Pd(II) adsorbent.
