Comparative Analysis of Nanomaterial Impacts in Production Processes

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1 Comparative Analysis of Nanomaterial Impacts in Production Processes Tess Garvey, Dr. Gabrielle Gaustad and Dr. Callie Babbitt Sustainable Nanotechnology Conference November 4, 2013

2 Nanomaterials in Consumer Products Growing in sheer number and diverse in application Project on Emerging Nanotechnologies, 2013

3 Previous Work What is currently done in LCA of nanomaterial-containing products Nanomaterials LC stages Products What are the gaps in current LCA methods, inventories and impacts?

4 Review of Previous LCA Gavankar et al 2012

5 Review of Previous LCA Nanomaterials: Carbon-based, Silver, Titanium, Quantum Dots, Various Oxide NPs LC stages: Primarily Manufacturing Products: electronics, textiles, etc. but focus is on nanomaterial itself primarily

6 Review of Previous LCA Nanomaterials: Carbon-based, Silver, Titanium, Quantum Dots, Various Oxide NPs LC stages: Primarily Manufacturing Products: electronics, textiles, etc. Gaps: None of the LCA studies on ENMs or nanoproducts that we came across assessed nano-specific fate, transport, and toxicity effects citing the lack of data Gavankar et al. 2012

7 Previous Work on Impacts of CNT Eckelman et al, 2012

8 Research Question How do results of previous LCA change when nanomaterial emissions are included? How can we address these gaps without new data? Scenario analysis using realistic and worst case estimates for emissions and impacts

9 Scope Raw material extraction for material precursors and energy requirements Emissions to environment Processing Production and Synthesis Nano emissions to air, water, soil Functional Unit of nanomaterial

10 Impact Assessment USEtox Manual, 2010

11 Impact Assessment Characterization Factor (CF) = Fate x Exposure x Effect Impact (PAF, CTU)= Mass Emitted x Characterization Factor Emissions Characterization Factor Realistic Synthesis and Purification Yields, Removal during WWT Middle of the road effect from literature, moderate fate & exposure Worst Case All NMs are emitted directly to freshwater The lowest effect in literature, long fate & high exposure

12 Case Studies Major categories of nanomaterials: 1) Carbon-based (SWNT) 2) Metal oxides (TiO 2 ) 3) Metals (Ag) Project on Emerging Nanotechnologies, 2013

13 Single Wall Carbon Nanotubes Cobalt Magnesium Ammonium Methane Argon Citric Acid Ethanol Hydrogen (CVD) SWNT synthesis Methane Argon Hydrogen DI water DI water Nitric acid Purification Filtrate Non-nano Emissions Functional Unit of SWNT SWNT Emissions Healy et al. 2008

14 Ecotoxicity Impact of SWNT 100% 90% 80% 70% 60% 50% 40% Electricity Nitric acid Deionised water Argon Hydrogen Methane Organic chemicals 30% Cobalt 20% Magnesium 10% Ammonium 0% Realistic Release Worst Case SWNT release

15 Potentially Affected Fraction (PAF) Ecotoxicity Impact of SWNT No Nano Emissions Realistic release of SWNT Worst Case Release

16 Nano TiO 2 Manufacture Iron Powder HCl Ilmenite Methane Electricity Steam Nano-TiO 2 manufacture via Altair Hydrochloride Process Non-nano Emissions Functional Unit of nano-tio 2 Nano TiO2 emissions Grubb and Bakshi 2011

17 Ecotoxicity Impact of TiO 2 Manufacture 100% 90% Steam 80% Electricity 70% 60% Methane 50% Iron ore 40% 30% Ilmenite 20% HCl 10% 0% Realistic Release Worst Case Scenario Nano-TiO2 release

18 PAF Ecotoxicity Impact of TiO No Nano Release Realistic TiO2 Release Worst Case Release

19 Nanosilver Manufacture via FSP 2-ethylhexanoic acid Silver-octanoate Methane Tap water Xylene Oxygen Electricity Nanosilver Manufacture via Flame Spray Pyrolysis (FSP) Nano Ag Emissions Functional Unit nano Ag Non-nano Emissions Walser et al. 2011

20 Ecotoxicity Impact of Nanosilver Manufacture 100% 90% 80% 70% 60% 50% 40% 30% 20% Electricity Xylene Tap water Oxygen Methane Nano Ag 10% 0% Realistic release Worst Case Scenario

21 PAF Ecotoxicity Impact of Nanosilver No Nano Release Realistic release Worst Case Scenario

22 Implications of Results Nano impacts can have a significant influence on results and are not always smaller than non-nano (e.g. energy, chemical and material use) impacts Highlight chemical use, energy use or nano emissions likely contributes most impact for future R&D Chemical reuse or substitution Energy efficiency Control technologies for nanomaterial release

23 Gaps Other Impact Categories Improved data quality for released fraction Can have significant influence on impact results Fate/transport data Use of USEtox model Uncertainty Metrics for Impact Assessment

24 Expanding this Work Analysis to other production methods including green syntheses Use of different functional unit based on global production volumes or product-based Expansion beyond manufacture to use and disposal or reuse

25 Questions?

26 Nano TiO 2 Manufacture Grubb and Bakshi 2011