Dissolution kinetics of Pd and Pt from automobile catalysts by naturally occurring complexing agents

► Highest release of PGE from catalysts occur under acidic and alkaline conditions. ► Mobilisation of PGE is highest in citric acid and Na-pyrophosphate solutions. ► Hydroxyl complexes predominate in the speciation of PGE in the extracts. ► Low release of PGE in fulvic acid solution due to readsorption.