Metal Recovery and Recycling by Urban Mining. Prof. Jason Love EaStCHEM School of Chemistry, University of Edinburgh

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1 Metal Recovery and Recycling by Urban Mining Prof. Jason ove EaStCHEM School of Chemistry, University of Edinburgh

2 Secondary sources and resource recovery Consumer manufacture Re-use/ repair design recycle Jones et al., J. Clean. Prod., 2013, 55, Enhanced landfill mining in view of multiple resource recovery: a critical review Urban mining Technological requirement Processing urban mine (WEEE) materials with high metal content Processing landfill/tailings/legacy materials with low metal content

3 The case for urban mining Focus on Waste Electronic and Electrical Equipment (WEEE) EU-28 12% increase in WEEE (note: 98 and 145% in China and India) 1-5 g gold For Cu and Al 85-95% energy saving compared to mining and refining 1 tonne rock 12% of gold consumed by electronics industry Gold is the most valuable component of WEEE 1 tonne WEEE, e.g. smartphones 300 g gold 40% of WEEE in uncontrolled landfill WEEE waste sites 100x more contaminated by heavy metals

4 Hydrometallurgy energy and resource efficiency Pregnant each Solution Single Metal Solution Metal ore or other source each Separation & Concentration Reduction Pure Metal

5 Chemical understanding of metal recovery processes The Metal Recovery Edinburgh University Jason B. ove Professor of Molecular Inorganic Chemistry jason.love@ed.ac.uk Carole A. Morrison Reader in Computational Chemistry carole.morrison@ed.ac.uk We aim to: Understand the chemistry that underpins metal recovery from primary and secondary sources Identify molecular level solution structure using experiments, spectroscopy, and computation Develop new reagents for metal recovery by solvent extraction Solvent extraction Solution chemistry For a brief overview see page 154:

6 Chemical recognition of metals Chemical knowledge underpins our understanding of metal recovery processes e.g. different solution structures are seen depending upon metals, leachate, extractant, and solvents Cu + Cu aqueous organic organic Chem. Soc. Rev., 2014, 43, 123 metal cation X metal cation X X metalate receptor + receptors H 2 O H 2 O H 2 O metalate H + H 2 O H 2 O H 2 O Complexes Synergists Ion Pairs Reverse Micelles

7 Urban mining a smartphone Very high metal content: 38% ferrous, 16% non-ferrous Need highly selective recognition for single metals: 60 elements in a smartphone each Extract Zn Au 2 M hydrochloric acid (HCl) 2.37 M copper; 0.61 M iron; 0.57 M aluminium; 0.28 M tin; 0.24 M nickel; 0.11 M zinc; M gold Al Sn Ni Fe Cu

8 Gold recovery from WEEE We have discovered a simple amide for the selective recovery of gold from waste electronics Angew. Chem. Int. Ed., 2016 Metal concentration / mol Sn Au Au Stock Neat MIBK MIBK Neat DBC Neat 2-EH 2-EH 0.1 M 1 O Amide DBC 1 o Amide Other metals in large excess compared with [Au] 0.0 Cu Al Zn Ni Fe Sn Au Metal 1 o amide gets Au, and a lot less Fe/Sn

9 Gold recognition by protonated amide receptor We have used slope analysis, EXAFS, mass spectrometry, and DFT/MD calculations to identify the mechanism of gold recovery by solvent extraction

10 ow energy processes to high value products We believe that chemists, in collaboration with biologists, engineers, and industry can generate more economically and environmentally efficient metal recovery processes Chemistry solutions Bio-leaching Heap leaching solubility stability synthesis strength selectivity Solvent extraction speed separation Precious resource Au Ag Pt Ir system safety Engineering solutions

11 Technological solutions for recycling from the urban mine 1. Recycling of valuable and toxic metals Dr Carole. A. Morrison Metal recycling from waste electronic and electrical Prof. Jason B. ove equipment (WEEE) Challenges: eaching; selective separations; economy of scale 2. New materials from waste materials Sustainable cement, waste materials embedded in cement mixes Challenges: Impact of waste fillers on product; material consistency Dr Caroline Kirk Materials chemistry Energy and environment Formation of natural materials 3. Recycling of plastics Depolymerisation and regrowth of aromatic and aliphatic polyesters Challenges: Selectivity; plastic separation; transition of technology Prof. Michael P. Shaver Polymer synthesis igand and catalyst design ROP/radical polymerization UoE Director SOFI

12 Conclusions 1. Waste electronic and electrical equipment is a valuable resource 2. Chemistry is integral to metal recovery 3. Dynamic assembly can generate complexity from simple inputs 4. Collaboration between chemists, engineers, economists, and industry is essential Thanks Euan Doidge Innis Carson Carole Morrison Peter Tasker Ross Ellis Jamie Hunter WEEE 2 0 sources Solvent extraction Gold

13 Further Reading E. D. Doidge, I. Carson, J. B. ove, C. A. Morrison, P. A. Tasker, The influence of the Hofmeister bias and the stability and speciation of chloridolanthanates on their extraction from chloride media, Solvent Extraction Ion Exchange, 2016, 34, M. R. Healy, J. W. Roebuck, E. D. Doidge,. C. Emeleus, P. J. Bailey, J. Campbell, A. J. Fischmann, J. B. ove, C. A. Morrison, T. Sassi, D. J. White, P. A Tasker, Contributions of inner and outer coordination sphere bonding in determining the strength of substituted phenolic pyrazoles as copper extractants, Dalton Trans., 2016, 45, I. Carson, K. J. MacRuary, E. Doidge, R. J. Ellis, R. A. Grant, R. J. Gordon, J. B. ove, C. A. Morrison, G. S. Nichol, P. A. Tasker, A. M. Wilson, Anion receptor design: exploiting outer-sphere coordination chemistry to obtain high selectivity for chloridometalates over chloride, Inorg. Chem., 2015, 54, M. R. Healy, E. Carter, I. A. Fallis, R. S. Forgan, R. J. Gordon, E. Kamenetzky, J. B. ove, C. A. Morrison, D. M. Murphy, P. A. Tasker, EPR/ENDOR and computational study of outer-sphere interactions in copper complexes of phenolic oximes, Inorg. Chem., 2015, 54, J. R. Turkington, P. J. Bailey, J. B. ove, A. M. Wilson, P. A. Tasker, Exploiting outer-sphere interactions to enhance metal recovery by metal extraction. Chem. Commun., 2013, 49,