Nanohydrometallurgical extraction of gold based on ranelate induced nanoparticles formation

Author(s)

Mattioni, Joao V. ; Franciscato, Douglas S. ; Melo, Fernando M. ; Sihn, Luca M. ; Brandao, Bruno B. N. S. ; Condomitti, Ulisses ; Nakamura, Marcelo ; Toma, Henrique E.

• Document type: Journal article
• Source: HYDROMETALLURGY; v. 213, p. 10-pg., 2022-07-06.

Abstract

Most known for its medicinal anti-osporotic properties, the ranelate ion exhibits an exceptional performance in reacting with gold(III) ions, generating stable gold nanoparticles (AuNP@Ran). The reaction proceeds rapidly at room temperature, under green, mild conditions. The AuNP@Ran nanoparticles are relatively inert in aqueous solution, and exhibit zeta potentials of about -50 mV at pH 6. This fact has been explored in this work for interacting with positively charged magnetite nanoparticles, leading to a novel magnetic nanohydrometallurgy method for the extraction of gold. The process has been investigated in detail, by monitoring the extraction and constructing the adsorption isotherms, using electronic and Raman spectroscopy. The nature of the nanoparticles association has been elucidated by exploring the SERS effect. The proposed method is able to extract even trace amounts of gold from aqueous solution. For its simplicity and safety, it can be a green alternative to most conventional gold extraction processes, without using harmful and toxic reagents, such as mercury and cyanide ions. (AU)

• FAPESP's process: 19/14771-5 - Development of superparamagnetic nanoparticles functionalized with complexing agents for the capture and exploitation of strategic metals
• Grantee: João Victor Mattioni
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 18/21489-1 - Supramolecular nanotechnology: design, materials and devices
• Grantee: Henrique Eisi Toma
• Support Opportunities: Research Projects - Thematic Grants