Recovery of Platinum from Chloride Leaching Solutions of Spent Reforming Catalysts by Ion Exchange

摘要

Platinum and base metals (Al, Fe, Si) are present in the chloride leaching solutions of spent reforming catalysts. In order to develop a process to recover platinum from such leaching solutions, batch and continuous ion exchange experiments were performed using a strong anionic resin (DiaionSA10AP). The adsorption equilibrium data of Pt are described by the Langmuir adsorption isotherm. Batch experiments indicate that it is possible to separate Pt and Fe from other metal ions in the present leaching solution. Fe was selectively removed from the loaded resin using diluted HCl, while Pt was eluted using thiourea after Fe removal. The results of column experiments verified the feasibility of the separation and recovery of platinum from leaching solutions using the present process. The elution efficiency exceeded 99% for both Pt and Fe. The recovery percentage of Pt from the leaching solution using this method was 99.3%.