Postgraduate Seminar Presentation : Bio-hydrometallurgical Recovery of Platinum Group Metals from Spent Auto Catalysts

Speaker Salman Karim (Supervisor: A/Prof Ting Yen Peng)

Host Department of Chemical and Biomolecular Engineering

Date/Time 10 Aug - 10 Aug, 10.00am

Venue E5-02-32 , Faculty of Engineering, National University of Singapore


Platinum group metals (PGMs) i.e. platinum, palladium, and rhodium play a decisive role in the performance of automotive exhaust systems, worldwide applied in vehicles as automotive catalytic converters, to reduce the emission of gaseous pollutants. These catalysts consume a major portion of the global production of PGMs, amounting to 50% of produced platinum, 80% of rhodium, and 80% of palladium. The recovery and recycling of PGMs from spent automotive catalysts (SAC) are important due to the need for resource conservation, economic benefits, and environmental protection.

Most of the published studies on the PGMs recovery have considered only pyrometallurgical and hydrometallurgical techniques which have major drawbacks such as the generation of liquid waste and hazardous secondary pollutants. The present study aims to recover the PGMs from SAC under environmentally-friendly conditions.

Our preliminary results showed that mesophilic bacteria Pseudomonas fluorescens and Bacillus megaterium produce cyanide as a secondary metabolite can recover a considerable amount of PGMs from SAC. Currently, recovery of 44% platinum, 54% palladium, and 98% rhodium are obtained under optimum conditions. Based on these results, we aim to optimize further the recovery of PGMs using various strategies such as pretreatment and the use of pure and mixed culture, as well as biomineralization.