Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Selective recovery of precious metals through photocatalysis

Abstract

Precious metals such as gold and platinum are valued materials for a variety of important applications, but their scarcity poses a risk of supply disruption. Recycling precious metals from waste provides a promising solution; however, conventional metallurgical methods bear high environmental costs and energy consumption. Here, we report a photocatalytic process that enables one to selectively retrieve seven precious metals—silver (Ag), gold (Au), palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru) and iridium (Ir)—from waste circuit boards, ternary automotive catalysts and ores. The whole process does not involve strong acids or bases or toxic cyanide, but needs only light and photocatalysts such as titanium dioxide (TiO2). More than 99% of the targeted elements in the waste sources can be dissolved and the precious metals recovered after a simple reducing reaction that shows a high purity (≥98%). By demonstrating success at the kilogram scale and showing that the catalysts can be reused more than 100 times, we suggest that this approach might be industry compatible. This research opens up a new path in the development of sustainable technologies for recycling the Earth’s resources and contributing to a circular economy.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Photocatalytic dissolution of PMs.
Fig. 2: Photocatalytic selective dissolution of metals from metal catalysts (1% Cu/TiO2, 1% Ag/TiO2, 1% Au/TiO2 and 1% Pt/TiO2), CPU boards and e-waste powder.
Fig. 3: Reduction process of PM ions.
Fig. 4: Proposed mechanism of PM recovery.

Data availability

The data supporting the findings of the study are available within the paper and its Supplementary Information.

References

  1. 1.

    Fan, Z. & Zhang, H. Crystal phase-controlled synthesis, properties and applications of noble metal nanomaterials. Chem. Soc. Rev. 45, 63–82 (2016).

    CAS  Article  Google Scholar 

  2. 2.

    Zhao, M. et al. Metal-organic frameworks as selectivity regulators for hydrogenation reactions. Nature 539, 76–80 (2016).

    CAS  Article  Google Scholar 

  3. 3.

    Hunt, S. T. et al. Self-assembly of noble metal monolayers on transition metal carbide nanoparticle catalysts. Science 352, 947–978 (2019).

    Google Scholar 

  4. 4.

    Commodity Statistics and Information (USGS, 2017); https://minerals.usgs.gov/minerals/pubs/commodity/

  5. 5.

    Li, B. et al. Recovery of platinum group metals from spent catalysts: a review. Int. J. Miner. Process. 145, 108–113 (2015).

    Article  CAS  Google Scholar 

  6. 6.

    Annual Consumption and Storage of Metals in the World (NIMS, 2015); http://www.nims.go.jp/jpn/news/press/pdf/press215_2.pdf

  7. 7.

    Yavuz, C. T. et al. Gold recovery from e-waste by porous porphyrin–phenazine network polymers. Chem. Mater. 32, 5343–5349 (2020).

    Article  CAS  Google Scholar 

  8. 8.

    Liu, C. et al. Economic and environmental feasibility of hydrometallurgical process for recycling waste mobile phones. Waste Manag. 111, 41–50 (2020).

    CAS  Article  Google Scholar 

  9. 9.

    Dato, P. Economic analysis of e-waste market. Int. Environ. Agreem. 17, 815–837 (2017).

    Article  Google Scholar 

  10. 10.

    Doidge, E. D. et al. A simple primary amide for the selective recovery of gold from secondary resources. Angew. Chem. Int. Ed. 55, 12436–12439 (2016).

    CAS  Article  Google Scholar 

  11. 11.

    Sun, D. T., Gasilova, N., Yang, S., Oveisi, E. & Queen, W. L. Rapid, selective extraction of rrace amounts of gold from complex water mixtures with a metal-organic framework (MOF)/polymer composite. J. Am. Chem. Soc. 140, 16697–16703 (2018).

    CAS  Article  Google Scholar 

  12. 12.

    Liu, Z. et al. Selective isolation of gold facilitated by second-sphere coordination with alpha-cyclodextrin. Nat. Commun. 4, 1855 (2013).

    Article  CAS  Google Scholar 

  13. 13.

    Yue, C. et al. Environmentally benign, rapid, and selective extraction of gold from ores and waste electronic materials. Angew. Chem. Int. Ed. 56, 9331–9335 (2017).

    CAS  Article  Google Scholar 

  14. 14.

    McGivney, E. et al. Biogenic cyanide production promotes dissolution of gold nanoparticles in soil. Environ. Sci. Technol. 53, 1287–1295 (2019).

    CAS  Article  Google Scholar 

  15. 15.

    Birich, A., Stopic, S. & Friedrich, B. Kinetic investigation and dissolution behavior of cyanide alternative gold leaching reagents. Sci. Rep. 9, 7191 (2019).

    Article  CAS  Google Scholar 

  16. 16.

    Ahtiainen, R. & Lundström, M. Cyanide-free gold leaching in exceptionally mild chloride solutions. J. Clean. Prod. 234, 9–17 (2019).

    CAS  Article  Google Scholar 

  17. 17.

    James Hutton: father of modern geology, 1726–1797. Nature 119, 582 (1927).

  18. 18.

    Lee, H., Molstad, E. & Mishra, B. Recovery of gold and silver from secondary sources of electronic waste processing by thiourea leaching. JOM 70, 1616–1621 (2018).

    CAS  Article  Google Scholar 

  19. 19.

    Burdinski, D. & Blees, M. H. Thiosulfate- and thiosulfonate-based etchants for the patterning of gold using microcontact printing. Chem. Mater. 19, 3933–3944 (2007).

    CAS  Article  Google Scholar 

  20. 20.

    Cho, E. C., Xie, J., Wurm, P. A. & Xia, Y. Understanding the role of surface charges in cellular adsorption versus internalization by selectively removing gold nanoparticles on the cell surface with a I2/KI etchant. Nano Lett. 9, 1080–1084 (2009).

    CAS  Article  Google Scholar 

  21. 21.

    Parga, J. R., Valenzuela, J. L. & Francisco, C. T. Pressure cyanide leaching for precious metals recovery. JOM 59, 43–47 (2007).

    CAS  Article  Google Scholar 

  22. 22.

    Lopes, P. P. et al. Dynamics of electrochemical Pt dissolution at atomic and molecular levels. J. Electroanal. Chem. 819, 123–129 (2018).

    CAS  Article  Google Scholar 

  23. 23.

    Lin, W. et al. ‘Organic aqua regia’—powerful liquids for dissolving noble metals. Angew. Chem. Int. Ed. 49, 7929–7932 (2010).

    CAS  Article  Google Scholar 

  24. 24.

    Hong, Y. et al. Precious metal recovery from electronic waste by a porous porphyrin polymer. Proc. Natl Acad. Sci. USA 117, 16174–16180 (2020).

    CAS  Google Scholar 

  25. 25.

    Okesola, B. O., Suravaram, S. K., Parkin, A. & Smith, D. K. Selective extraction and in situ reduction of precious metal salts from model waste to generate hybrid gels with embedded electrocatalytic nanoparticles. Angew. Chem. Int. Ed. 55, 183–187 (2016).

    CAS  Article  Google Scholar 

  26. 26.

    Wang, H. et al. Semiconductor heterojunction photocatalysts: design, construction, and photocatalytic performances. Chem. Soc. Rev. 43, 5234–5244 (2014).

    CAS  Article  Google Scholar 

  27. 27.

    Cherevko, S. et al. Dissolution of noble metals during oxygen evolution in acidic media. ChemCatChem 6, 2219–2223 (2014).

    CAS  Article  Google Scholar 

  28. 28.

    Tian, J. et al. Kinetics on leaching rare earth from the weathered crust elution-deposited rare earth ores with ammonium sulfate solution. Hydrometallurgy 101, 166–170 (2010).

    CAS  Article  Google Scholar 

  29. 29.

    Zhou, J. et al. Leaching kinetics of potassium and aluminum from phosphorus-potassium associated ore in HCl-CaF2 system. Sep. Purif. Technol. 253, 117528 (2020).

    CAS  Article  Google Scholar 

  30. 30.

    Dong, C. et al. Size-dependent activity and selectivity of carbon dioxide photocatalytic reduction over platinum nanoparticles. Nat. Commun. 9, 1252 (2018).

    Article  CAS  Google Scholar 

  31. 31.

    Sun, C. & Xue, D. In situ IR spectral observation of NH4H2PO4 crystallization: structural identification of nucleation and crystal growth. J. Phys. Chem. C 117, 19146–19153 (2013).

    CAS  Article  Google Scholar 

  32. 32.

    Ennis, C., Auchettl, R., Ruzi, M. & Robertson, E. G. Infrared characterisation of acetonitrile and propionitrile aerosols under Titan’s atmospheric conditions. Phys. Chem. Chem. Phys. 19, 2915–2925 (2017).

    CAS  Article  Google Scholar 

  33. 33.

    Yu, H. L. et al. Unidirectional suppression of hydrogen oxidation on oxidized platinum clusters. Nat. Commun. 4, 2500 (2013).

    Article  CAS  Google Scholar 

  34. 34.

    Chaudhuri, P. et al. Electronic structure of bis(o-iminobenzosemiquinonato) metal complexes (Cu, Ni, Pd). The art of establishing physical oxidation states in transition-metal complexes containing radical ligands. J. Am. Chem. Soc. 123, 2213–2223 (2001).

    CAS  Article  Google Scholar 

  35. 35.

    Siemer, N. et al. Atomic scale explanation of O2 activation at the Au-TiO2 interface. J. Am. Chem. Soc. 140, 18082–18092 (2018).

    CAS  Article  Google Scholar 

  36. 36.

    Li, R. et al. Radical-involved photosynthesis of AuCN oligomers from Au nanoparticles and acetonitrile. J. Am. Chem. Soc. 134, 18286–18294 (2012).

    CAS  Article  Google Scholar 

  37. 37.

    Zheng, Z. et al. Facile in situ synthesis of visible-light plasmonic photocatalysts M@TiO2 (M = Au, Pt, Ag) and evaluation of their photocatalytic oxidation of benzene to phenol. J. Mater. Chem. 21, 9079–9087 (2011).

    CAS  Article  Google Scholar 

  38. 38.

    Bilski, J. et al. Photochemical reactions involved in the phototoxicity of the anticonvulsant and antidepressant drug lamotrigine (Lamictal@). Photochem. Photobiol. 85, 1327–1335 (2009).

    CAS  Article  Google Scholar 

  39. 39.

    Han, G. et al. Visible-light-driven valorization of biomass intermediates integrated with H2 production catalyzed by ultrathin Ni/CdS uanosheets. J. Am. Chem. Soc. 139, 15584–15587 (2017).

    CAS  Article  Google Scholar 

  40. 40.

    Hokuto, F. et al. Determining the composite structure of Au-Fe-based submicrometre spherical particles fabricated by pulsed-laser melting in liquid. Nanomaterials 9, 198 (2019).

    Article  CAS  Google Scholar 

  41. 41.

    Xiao, J. et al. Integration of plasmonic effects and schottky junctions into metal organic framework composites: steering charge flow for enhanced visible-light photocatalysis. Angew. Chem. Int. Ed. 57, 1103–1107 (2017).

    Article  CAS  Google Scholar 

  42. 42.

    Frens, G. Controlled nucleation for the regulation of the particle size in monodisperse gold suspensions. Nat. Phys. Sci. 241, 20–22 (1973).

    CAS  Article  Google Scholar 

  43. 43.

    Lee, P. C. & Melsel, D. J. J. Adsorption and surface-enhanced raman of dyes on silver and gold sols. J. Phys. Chem. 86, 3391–3395 (1982).

    CAS  Article  Google Scholar 

  44. 44.

    Liu, L., Gao, F. & Zhao, H. Tailoring Cu valence and oxygen vacancy in Cu/TiO2 catalysts for enhanced CO2 photoreduction efficiency. Appl. Catal. B 134–135, 349–358 (2013).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Key Research and Development Program of China (no. 2020YFA0211004), the National Natural Science Foundation of China (nos. 21876114 and 21761142011), Shanghai Government (nos. 19DZ1205102, 19160712900 and 18JC1412900), the Chinese Education Ministry Key Laboratory and International Joint Laboratory on Resource Chemistry, the Shanghai Eastern Scholar Program and the Shanghai Engineering Research Center of Green Energy Chemical Engineering (no. 18DZ2254200).

Author information

Affiliations

Authors

Contributions

Y.C., M.X., Z.B. and H.L. conceived the idea for the paper. Y.C. and Z.B. designed the experiments. Y.C., J.W. and Y.W. synthesized the material. Q.Z., Y.D., X.C. and Z.L.W. performed the high-angle annular dark-field STEM imaging. Y.C. performed the sample characterization. Z.B., Z.L.W. and H.L. conducted the experiments. Y.C. and Z.B. analysed the data and wrote the manuscript. All of the authors contributed to writing the paper.

Corresponding authors

Correspondence to Zhong Lin Wang or Hexing Li or Zhenfeng Bian.

Ethics declarations

Competing interests

The authors have filed a patent application (US Patent application no. 17042775) on technology related to the processes described in this Article.

Additional information

Peer review information Nature Sustainability thanks Sheng Dai, Bernd Friedrich and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–28 and Tables 1–4.

Reporting Summary

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Chen, Y., Xu, M., Wen, J. et al. Selective recovery of precious metals through photocatalysis. Nat Sustain (2021). https://doi.org/10.1038/s41893-021-00697-4

Download citation

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing