Bioleaching of platinum, palladium, and rhodium from spent automotive catalyst using bacterial cyanogenesis

Evaluation of green chemistry metrics for sustainable recycling of platinum group metals from spent automotive catalysts via bioleaching

“…17 Biometallurgical processes, such as bioleaching, have low energy requirements and need simple processing steps. 18,19 Prospective future recovery approaches are likely to emphasize economic and environmental imperatives instead of merely increasing the recovery rate. To date, there has been little data available on the assessment and quantification of environmental sustainability in the precious metal industry.…”

Recovery of catalytic metals from leaching solutions of spent automotive catalytic converters using plant extracts

“…To the best of our knowledge, by now, studied biohydrometallurgical procedures are mainly focused on the PGM bio-leaching from ACCs, benefiting from different organic acids or microorganisms. Bio-leaching processes employ organic acids such as oxalic or lactic acids (Wiecka et al 2022) or microorganisms including bacteria, such as reported by Ilyas et al (2022) and Karim and Ting (2022), or fungus like reported by Bahaloo-Horeh and Mousavi (2022). Nevertheless, it has been shown that microorganisms can also be used to separate PGMs from solutions by different mechanisms, including bio-reduction, bio-precipitation, chelation, extracellular sequestration and bio-sorption (Zhang et al 2020).…”

Recovery of palladium from waste fashion items through food waste by-products

“…Among others, pyrometallurgical or hydrometallurgical processes are available for Pd recovery. 14–17…”

“…Among others, pyrometallurgical or hydrometallurgical processes are available for Pd recovery. [14][15][16][17] The pyrometallurgical route is energy-intensive with high environmental impact, given the high melting point of Pd (1550 °C). Hydrometallurgy makes use of an oxidant and a lixiviant (usually aqua regia and cyanide) to dissolve metals.…”

“…In bio-hydrometallurgical routes, microorganisms are used to leach Pd, e.g., using bacterial cyanogenesis for the in situ production of cyanide. 17 Microorganisms can also separate Pd(II) by bio-reduction, bio-precipitation, chelation, extracellular sequestration, biosorption and metal uptake. 26 Plants' metabolites, including phenols, saponins, alkaloids, organic acids, proteins, etc., can reduce metal ions.…”