ACS Symposium: Sustainable Extraction of Critical Metals from Saline Water and Industrial Wastewater - Challenges & Opportunities
Sustainable Extraction of Critical Metals from Industrial Wastewater: Opportunities and Challenges ACS Presidential Symposium Tuesday August 21, 2012 Philadelphia, PA, USA
Mamadou DialloAssociate Professor and Director of theLaboratory of Advanced Materials and Systemsfor Water Sustainability, Graduate School of Energy,Environment, Water and Sustainability (EEWS), KAISTVisiting Faculty in Environmental Science and Engineering,Division of Engineering and Applied Science, CaltechChief Technology Officer and Founder of AquaNano, LLC
Outline• A. Industrial Wastewater as Sources of Critical Materials• B. Extraction of Critical Materials from Industrial Wastewater: Overview of Recent Advances• C. Concluding Remarks• D. Acknowledgments
Sustainable Supply of Critical Materials: Sources, Extraction, Recovery and Purification Computer Circuit Boards as Sources of Critical Materials (Johnson et al. Environ. Sci. Technol. 2007, 41, 1759-1765)
Wastes as Sources of Critical Materials: The Metals-Specific Sherwood PlotMetal prices (2004) as a function of dilution (1/concentration) of metals incommercial ores. This Sherwood plot illustrates the concept that the moredilute a material is in its native ore, the more expensive it will be to purifyinto a commodity material.David Allen. Adapted from Johnson et al. Environ. Sci. Technol. 2007, 41, 1759-1765)
Industrial Wastewater as Source of Critical Materials David Allen, MRS Bulletin, March 1992
Examples of Industrial Discharges of Wastewater Containing Metals• Metal Products and Machinery Industry (63,000 sites)• Metal Finishing Industry (44,000 facilities)• Metal Molding and Casting Industry ( > 700 facilities)• Mineral Mining and Processing• Nonferrous Metals Manufacturing• Semiconductor Industry These industries are all subject to the effluent guidelines promulgated by EPA, under 40 CFR’ of the Code of Federal Regulations (CFR).
Extraction of Critical Materials from Wastewater: Scientific Grand Challenges• Design and synthesize high capacity, recyclable and robust separation materials (e.g. chelating ligands, ion exchange media and sorbents) that can – Selectively extract critical materials from complex aqueous solutions (e.g., highly acid and/or saline media) – Be seamlessly integrated with existing separation equipment including (i) packed bed reactors, (ii) pressure vessels, (iii) clarifiers and (iii) membrane modules and systems.
Dendritic Macromolecules as High Capacity, Selective and Recyclable Chelating for Cu(II) and Ag(I)G4-NH2 PAMAM DendrimerSelectivity versus Capacity
Dendritic Macromolecules as High Capacity, Selective and Recyclable Chelating for Cu(II) and Ag(I) [Cont]Diallo et al. Langmuir. 2004, 20, 2640-2651 160 G4-NH2 pH 7 replicate 1 140 G4-NH2 pH 7 replicate 2 120 G4-NH2 pH 7 replicate 3 G4-NH2 pH 9 100 G4-NH2 pH 5 EOBmax2=74.0 80 60 40 20 EOBmax1=12.0 0 0 20 40 60 80 100 120 140 160 Metal-Ion Dendrimer Loading (mole/mole)At pH 9.0, the G4-NH2 PAMAMdendrimer binds more than 100 Cu(II)Ions at pH 9.0.At pH 5.0, we observe no binding ofCu(II) to the G4-NH2 PAMAM dendrimer.
Extraction of Cu(II) and Ag(I) from Solutions Using Dendrimer Enhanced UltrafiltrationDiallo, M.S. Water Treatment by Dendrimer-Enhanced Filtration (US Patent7,470,369) Highly branched and water-soluble macromolecules with tunable ion binding sites • Large size allows for low pressure membrane (MF/UF) separation • Easily integrated into existing treatment systems • Scalable – for small and large scale applications
Case Study: Recovery of Cu(II) from Aqueous Solutions by Crossflow Dendrimer Enhanced FiltrationDiallo et al. Environ. Sci. Technol. 2005, 39, 1366-1377Crossflow GE Osmonics Sepa Cell .
Prototype of First Generation Dendrimer Enhanced Filtration System (AquaNano, LLC)UF 1: IMT Multibore Ultrafiltration Membrane: Membrane: Bore Size: 0.9 mm Chemistry: Modified PES MWCO: 100 to 150 kD Active Area: 0.5 m2 Operation: Nominal Flow: 40 L/hr Flux: 75 L/m2/hrUF 2: X-Flow Tubular Ultrafiltration Membrane: Could achieve large water recovery (> 95%) Membrane: Bore Size: 8.0 mm and concentration factor (> 4000) Chemistry: Modified PES MWCO: 100 to 150 kD Active Area: 0.3 m2 Operation: Nominal Flow: 17 L/hr Flux: 55 L/m2/hr
Acknowledgments ( US:Caltech, AquaNano, etc ) Team) Program)• Senior Collaborators: Prof. William A. Goddard III (Caltech), James H. Johnson (Howard U), Prof. Jean Frechet (UC-Berkeley), Prof. Donald Tomalia (Central Michigan University) and Dr. Glenn Waychunas (Lawrence Berkeley National Laboratory)• Staff Scientists and Post Doctoral Research Associates : Dr. Vyacheslav Bryantsev (Caltech), Dr. Tapan Shah (Caltech), Dr. Joytsnendu Giri (Caltech), Dr. Yi Liu (Caltech), Dr. CJ Yu (AquaNano), Dr. Emine Boz (UC-Berkeley), Dr. Samuel Webb (Stanford Synchrotron Radiation Laboratory) and Dr. Pirabalina Swaminathan (Howard U)• Graduate and Undergraduate Students: Simone Christie (Howard U), Sa’Nia Carasquero (Howard U), Kwesi Falconer (Howard U), Mary Maneno (Howard U), Elijah George (Howard U), Margaret Barris-Milman (Caltech) and John Howard (Caltech)• US National Science Foundation (Funding)• US EPA STAR Program (Funding)• Aqua Nanotechnologies (Funding)• Stanford Synchrotron Radiation Laboratory (EXFAS and XANES Experiments)• Advanced Light Source of Lawrence Berkeley National Laboratory (NEXAFS Experiments)
Acknowledgments (Korea: KAIST)• Senior Collaborators: Prof. Yousung Jung (KAIST Graduate School of EEWS) and Prof. William A. Goddard III (KAIST Graduate School of EEWS)• Staff Scientists and Post Doctoral Research Associates : Dr. Seongjik Park (KAIST) and Dr. Chidralaravi Kumar (KAIST)• Graduate Students: Man-Ki Cho (KAIST), Doyeon Lee (KAIST), Dennis Chen (KAIST) and Sang Lee (KAIST)• KAIST EEWS Initiative (Funding)•