Recovery of precious metals from industrial wastewater towards resource recovery and environmental sustainability: A critical review

Nowadays, the recovery processes of precious metals (PMs) from industrial wastewater streams have found significant attractions among various investigators worldwide. PMs are known as rare/noble chemical elements that their fundamental characteristics such as ductility, electrical conductivity, and resistance against corrosion have made them promising for application in industrial-based activities such as jewelry, petrochemistry, and catalysis. The main objective of this review paper is to provide an opportunity for expert as well as non-expert readers to be familiar with the state-of-the-art breakthroughs in the recovery of PMs (i.e., gold (Au), silver (Ag), platinum (Pt), palladium (Pd), ruthenium (Ru), rhodium (Rh), iridium (Ir), osmium (Os), Rhenium (Re) and so on.) from wastewater streams. Apart from the explanation of industrial applications, the recovery process of PMs using various approaches is aimed to be interpreted comprehensively. Eventually, the advantages and disadvantages of applied techniques for the recovery of PMs are discussed, and different approaches as well as future perspectives towards their sustainable use are introduced.