%0 Journal Article %T Behavior of Platinum Group during Their Pyrometallurgical Recovery from Spent Automotive Catalysts %A Georgios Kolliopoulos %A Efthymios Balomenos %A Ioanna Giannopoulou %A Iakovos Yakoumis %A Dimitrios Panias %J Open Access Library Journal %V 1 %N 5 %P 1-9 %@ 2333-9721 %D 2014 %I Open Access Library %R 10.4236/oalib.1100736 %X
The behavior
of platinum group metals (PGMs) during their recovery with smelting of spent automotive
ceramic catalysts powder in the presence of metallic copper at elevated
temperatures is studied in this paper. Two different metal recovery mechanisms
proved to be active in this process: 1) Wetting of micro-dispersed particulates
of PGMs in the slag by molten copper, formation of copper droplets with
attracted microparticles of PGMs and settling of the molten droplets of Cu- PGMs
alloy through the slag at the bottom of the crucible (ˇ°wettingˇ±); 2) Settling
of solid PGMs microparticles through the molten slag and formation of a solid
solution with the molten copper at the bottom of the crucible (ˇ°settlingˇ±). The
PGMs are divided in two separate groups. Platinum has under the same
experimental conditions substantially higher recovery in comparison with the
palladium and rhodium that behave as a group having almost identical
recoveries. The heavier Pt is recovered primarily in big extent (almost 88%)
through the ˇ°settlingˇ± mechanism while Pd and Rh are recovered following a more
balanced mixture of both mechanisms with the ˇ°settlingˇ± one to be again more
important (66% for Pd and 57% for Rh). Slag viscosity is the most important
physical property and the design of an appropriate slag system is the most
important issue in developing an efficient process for the recovery of PGMs.