What Nano-Apps tells us about Nano-Imps

Transcription

1 What Nano-Apps tells us about Nano-Imps Greg Lowry Professor of Civil & Environmental Engineering Deputy Director-CEINT Carnegie Mellon University SNO, November 3, 2013

2 Nanotechnology Control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena arising from its size enable novel applications. Water Treatment Lighter and stronger materials Remediation Energy

3 Nanomaterials can be Unique Compared to their Bulk Counterparts Percent atoms on surface 90 Mn 2+ oxidation on n-fe 2 O 3 45 Auffan et al., 2009 Nature Nanotechnology 3 (4) Metals And Metal Oxides

4 Origin of Nanoscale Phenomena

5 What Processes Must be Controlled for Manufacturing and Application? Aggregation Attachment to surfaces Distribution in a polymer matrix Selectivity towards targets Reactive lifetime

6 Assessing the Risks of Engineered Nanomaterials Factors Influencing Exposure Aggregation Attachment to surfaces Transformation Distribution Biouptake Risk Characterization Factors Influencing Effects? Redox activity ROS Transformation

7 Balancing Risks and Benefits of Nanomaterials LC Nano-New NSF Center November, 2013

8 Conceptual Model of NZVI Barrier for In Situ GW Remediation Requires 1. Sufficient reactivity AND selectivity 2. Ability to be emplaced 3. Synergy with microorganisms 4. Safe

9 Reactive Fe 0 Nanoparticles (NZVI) Contaminants are reduced Nano Fe 0 is oxidized Fe 0 TCE Acetylene Fe 3 O 4 Fe 0 Fe 0 Fe 3 O 4 H 2 H + Fe 3 O 4 Lifetime depends on oxidant loading, ph, and potentially on microbial activity H + is reduced Liu et al, (2005) ES&T 39, 1338 Liu and Lowry, (2006) ES&T, 40 (19) 6085 Liu, et al., (2007) ES&T

10 Differences in Reactivity with TCE Fe(B) RNIP Faster Reaction k obs =1.4 x 10-2 L hr -1 m -2 Saturated Products Slower reaction k obs =3 x 10-3 L hr -1 m -2 Unsaturated Products *Iron Filings k=10-3 to 10-4 L hr -1 m -2 Liu, et al., Environ. Sci. & Technol. 2005, 39,

11 Manipulating NZVI properties by Synthesis Method RNIP Fe 0 core Fe 3 O 4 shell Crystalline FeOOH Fe 0 Fe 0 /Fe 3 O 4 (311) (110) Intensity (a.u.) (a) (b) (220) (222) (400) (422) (511) (440) (200) Fe(B) Fe 0 core Borate shell (c) (degree) X-ray Amorphous Fe 2+ + BH 4- Fe 0 /FeB x /Na 2 B 4 O 7 10 nm Liu et al, (2005) ES&T 39, 1338; Liu et al, (2005) Chem. Mat. 17(21); ;Nurmi et al. (2005) ES&T 39, 1221.

12 Higher Reactivity = Higher Toxicity

13 NZVI Oxidation Decreases ROS Production by CNS Glial Cells Fresh NZVI Aged NZVI Phenrat et al. (2009) ES&T 43 (1)

14 Conceptual Model of NZVI Barrier for In Situ GW Remediation Requires 1. Sufficient reactivity AND selectivity 2. Ability to be emplaced 3. Synergy with microorganisms 4. Safe

15 F=10-5 (~80 mg/l) Aggregation makes emplacement difficult 1-min NZVI sedimentation in 1 mm NaCl Aggregation I t crit 4 mg/l 25 micron 9-min t= 156 t = mg/l t = 294 d p ~45 mm 470 mg/l 25 micron 35-min Sedimentation I t = 1,111 Sedimentation II 690 mg/l 1130 mg/l d p ~120 mm 25 micron Phenrat T., et al., (2007) ES&T 41, 284.

16 Polymer Modified NZVI Nanoiron (RNIP) Surface modifiers + TCE + Fe 0 HC Products + Cl - + Fe 2+ /Fe 3+ PSS PAP Liu et al, (2005) ES&T 39, 1338 Liu and Lowry (2006) ES&T 40, 6085 Liu et al., (2007) ES&T 41, Saleh et al., (2007) EES 24, 45. Moderately stable dispersions

17 Surface Coatings Affect Attachment & Reactivity Inhibits Aggregation Charge Stabilization - Steric Stabilization Inhibits Deposition Saleh et al., 2008 ES&T 42 (9) Cl Cl Cl Cl C C Cl Cl C C Cl Cl Cl H C C Cl H C C Cl H Cl H Cl Cl Cl Cl C C C C Cl H Cl H Tail Cl Cl Cl Cl C C C C Cl Cl Cl H Cl H C C Cl H Loop Cl d Cl Cl Cl C C Cl C C H Cl Cl Cl H C C Cl Cl Cl Train H Cl Cl C C Cl C C H Cl H Decreases Reactivity Phenrat et al., 2008 ES&T Affects Nano-bio interactions water solvent RNIP Li et al. ES&T (ASAP) Phenrat et al. (2009) EST 43 (1) 195.

18 Modifiers Inhibit Aggregation Aggregation I t crit PSS70K Sedimentation I Sedimentation II PSS1M CMC90K Bare Polymers inhibit aggregation and provide a stable fraction No apparent trend with MW Saleh, N. et al. (2005). Nano Lett. 5 (12) Saleh, N. et al., (2007) Environ. Eng. Sci. 24 (1) p Phenrat, et al., (2008) J Nanopart. Res. 10 p No trend with apparent zeta potential

19 Configuration of Adsorbed Homopolymer Low concentration of adsorbed polymer RNIP RNIP RNIP High concentration of adsorbed polymer RNIP d M Important parameters: Adsorbed mass and layer thickness (d M )

20 Deposition is Determined from Breakthrough Curves and Filtration Theory o o c o e n a C C ) 3(1 4 ln Collisions that stick Total Collisions

21 Correlations to Predict Do Not Account for Adsorbed Macromolecules x10 N Lo N E1 N E2 N DL Bia and Tien, 1999 Ratio>>1 over predicts attachment 80 data points Phenrat, et al. ES&T

22 Better Predictability Using the Modified Correlation N LEK 1 d p d 2 M u s mm N W a p d M d M 0 I I ave 2 / 3 pre N 0.39 LO N 1.17 E1 N 0.10 LEK 1 Phenrat, et al. ES&T

23 Surface Modification with Polymer Decreases Reactivity with TCE PMAA 48 -PMMA 17 -PSS 650 modified RNIP: 10 times less reactive then unmodified RNIP, but still reactive enough Saleh, et al. Environ. Eng. Sci. 24 (1) 2007 p

24 Coatings Decreases TCE Diffusion to NP Surface but not H + Cl Cl C Cl C H Cl Cl C Cl C H Cl Cl C Cl C H Cl Cl C Cl C H Cl Cl C Cl C H Cl Cl C Cl C H Tail Cl Cl Cl Cl C C Cl C C Cl Cl H Cl H C C Cl H Cl Cl Cl Cl C C Cl C C H Cl Cl Cl H C C Cl H Cl Cl C C Cl H RNIP Train Loop Cl Cl C C Cl H Phenrat et al., 2009 ES&T 43 (5), pp 1507 d PSS70K-Modified NZVI Region I: Site blocking Region II: Site blocking and mass transfer limitation

25 Coatings Mitigate Bactericidal Effects of NZVI on E. coli 0 Coated NZVI Log(N/N 0 ) % Fe 0 RNIP Anaerobic PSS Coated RNIP PA Coated RNIP NOM Coated RNIP MRNIP2 Bare NZVI Coated RNIP Time (minutes) Li et al., ES&T 44 (9)

26 Coatings Decrease OS response by CNS Microglia to NZVI, BUT. Bare PAP-coated Phenrat et al. (2009) ES&T 43 (1)

27 Polyaspartate coated Fe 0 nanoparticles entered the Microglia cell nucleus N27 Neurons PAP-coated NZVI Phenrat et al. (2009) ES&T 43 (1)

28 Silver Nanoparticles Antimicrobial Membranes and Fabrics O 2 Ag +

29 Ag NPs Sulfidize and Decrease Ag + Release Ag 2 S(s) Ag + + S 2- K=6x10-51 M 2 Ag 2 S (am) O 2 /HS - Ag(0) Ag 2 S (crys) Greater S/Ag Ag + Sulfidation greatly decreases Ag + release Time Levard et al., ES&T (12), 5260.

30 Sulfidation Decreases Toxicity? Zebrafish Killifish C. Elegans Duckweed Levard, Hotze, et al., ES&T (in press)

31 Toxicity Correlates with Available Ag + Most Toxic Least Toxic Levard, Hotze, et al., ES&T (in press)

32 Conclusions Applications and implications research is asking many of the same questions Reactivity and Lifetime Effect of Coatings Transport and Exposure Effects/Efficacy Can optimize applications and minimize implications in some materials

33 Great Home for Mechanistic Work! Vicki Grassian (Editor) Christy Haynes (vice Editor)

34 Can we Optimize Apps and Minimize Imps?

35 Still No ROS after Aging

36 Complex Feedback from NOM Control AgNO 3 GA Ag-NP PVP Ag-NP Water only Plants only Sediment only Plants + Sediment Unrine et al., ES&T 46: Bone et al., ES&T 46:

37 Unrine et al., ES&T 46: Bone et al., ES&T 46: Stable primary particles (reduced toxicity) Silver ions, Particles Aquatic Plants Dissolution, Surfaces (reduced toxicity) Surface modification Exudates/ Lysates (-SH) Oxidation PVP-Ag NPs GA-Ag NPs

38 MW distribution (SEC-MALS) Suwannee River NOM Au NP aggregation (DLS) 100 mm NaCl No NOM 98 wt% Solvent (DI water) 1.8 wt% Whole NOM M w = 23 kg/mol Retentate M w = 691 kg/mol Filtrate M w = 13 kg/mol Filtrate NOM Small reduction in aggregation Retentate NOM Good stability (steric effects) Whole NOM Better stability than filtrate alone 38 Louie et al., 2013, ES&T, 47: 4245

39 Summary and Next Steps Some unique risks from nanomaterials Novel reactivity risk is low Ag NP toxicity predicted from Ag ion availability ZnO NPs yield same species as Zn ion and control Evidence of spatial and temporal uniqueness Effects on N-cycling at realistic doses Environmental transformations matter! Sulfidation of Ag ZnO CuO System complexity and feedbacks must be considered (See Melanie Auffan talk Thursday)

40 Dynamic Life Cycle Assessment LC Nano-New NSF Center October 23, 2013

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42 Thank You for your attention! Acknowledgements

43 Can we Correlate ENM Intrinsic Properties to their Effects? Yes, but is it relevant? Band gap photoactivity ROS toxicity? What extrinsic properties or parameters can predict overall behavior? ZnO TiO 2 - Zn 2+ OH Attachment efficiency Solubility/ Diss. rate ROS prod. rate Affinity for NOM Average Density

44 Should We Care About Engineered Nanoparticles? Values are in Tg/yr Hochella et al., 2012 In Nature s Nanostructures, Pan Stanford Publishing

45 Despite Sulfidation, Ag Biouptake Persists Loads in sediment dwelling organisms and fish were way above background Roots (20 mg/kg) Lowry et al., ES&T (13), pp

46 Uptake of Ag by Aquatic Plants Duckweed Landoltia punctata 18 h AgNO 3 AgNPs Ag 2 S-NPs ~60 h Dead Stegemeier et al., ES&T (in prep)

47 Polymer Coatings Limit NP-Bacteria Interactions and Toxicity Li et al., ES&T 44 (9) SRHA Chen et al., 2011 Wat. Res. 45 (5) 1995

48 Very Recent Novel Nanomaterials Malola et al., 2013, ACS Nano Lin et al., 2013, NanoLett. Liao et al., 2013, NanoLett.

49 Plume Concentration Contaminant Source Zone Treatment Using NZVI Nanoiron Injection MCL NO ACTION SOURCE REMOVAL POST REMOVAL Reduce source mass (Dm) and mass emission downgradient. Cost-effectiveness relies on iron properties and effective placement.

50 NP Attachment and Deposition Ce 4ac ln Co 3(1 n) o o Objectives: Predict NP distribution in Mobile? Immobile environment based on Predict removal efficiency in water treatment Include chemistry of macromolecular coatings

51 Number of Consumer Products Claiming to Contain Engineered Nanomaterials Number of products Year 1628 Data replotted from Project on Emerging Nanotechnologies, 3

52 Leitch, et al., 2012 JNR 14 p. 1283

53 Field Application of NZVI =53 Depends on: Chemical ph, ionic strength, ionic composition, surface coating Physical flow velocity, particle/aggregate size,

54 Novel Properties on NZVI Unit Cell dimension ~0.29 nm 1nm Crystals means ~4 3 unit cells per crystallite? Strained structure with high surface area/edge sites. Yields saturated products and can activate H 2 for dechlorination. Nurmi et al. (2005) ES&T 39, 1221.

55 NZVI Reaction with Water Decreases Reactive Lifetime Fe 0 2H Fe 2 H 2 Liu and Lowry, (2006) Environ. Sci. Technol., 40 (19) 6085

56 Effect of NZVI on Microbial Ecology Dechlorinatio n TCE Acetylene Ethene Ethane Reducing Conditions Hydrogen Production NZVI Direct Microbial Interaction Fe 2+ Increased Iron Concentration Polymer Addition 56

57 Alameda NZVI Shifts Microbial Communities due Jaccard (Opt:0.71%) (Tol 0.9%-0.9%) (H>0.0% S>0.0%) [0.0%-100.0%] Alameda to reducing conditions and H 2 Modified NZVI + TCE 1 Modified NZVI + TCE 2 Modified NZVI 1 Modified NZVI 2 NZVI 1 NZVI 2 NZVI + TCE 1 NZVI + TCE 2 TCE 1 TCE 2 Control 1 Control 2 Nano-magnetite 1 Nano-magnetite 2 Microcosms DGGE profiles from microcosms with NZVI cluster separate from those without NZVI NZVI stimulates sulfate reducer and methanogen populations Kirschling, et al., ES&T (2010) 44 (9) 3474.

58 What We Really Need? TCE H 2 O TCE H 2 O Core/shell particles Chloride and Products Chloride and Products

59 Field Application of NZVI =53 Depends on: Chemical ph, ionic strength, ionic composition, surface coating Physical flow velocity, particle/aggregate size,

60 Particle Size and Aggregation Limits Transport in Columns PSS-modified NZVI Breakthrough Small Mid Large PSS-modified hematite breakthrough Phenrat et al., 2009 Environ Sci. Technol. 43 (13) 5079

61 ph and Clay Minerals Affects Transport - - Low ph poor transport d - Elution (%) Poly(aspartate) coated NZVI ph6 ph7 ph8 + Silica Sand d 0 sand 2% fine 2% clay sand (300 ìm) fine(1.7 ìm) kaolin(1.36 ìm) High ph good transport Clay Kim et al. JCIS (in revision)

62 Removing Impurities from Sand Decreased ph Dependent Deposition ph6 ph7 ph8 PAP-hematite Acid washed sand ph<8 Elution (%) Sand ph<8 0 acid washed sand sand Kim et al., JCIS (in revision)

63 Most Important Hydrogeochemical Properties Affecting NZVI transport Coating Size Velocity ph Fines/clay Media Shape Affects NZVI aggregation Affects NZVI deposition

64 Engineered Nanomaterials are becoming more Unique Lim et al., Nature Materials 2010 Schumacher et al. NanoLett (ASAP) Yelin et al. NanoLett (ASAP)

65 What Properties are Exploited by Nanotechnology? Size and Structure (arrangement of atoms) Access to cells/brain (biouptake) Magnetic and optical properties (photonics) Material strength Reactivity Reactive oxygen species Reaction with contaminants (remediation and sensing) Rapid response (and reversibility)

66 Adsorbed Macromolecules Desorb Very Slowly High MW Greater adsorption energy Low MW Ln(C/C 0 ) 0.00 rapid slow PAP10K PAP2.5K Time (day) Γ= 1.47 (mg/m 2 ) 87 % Γ= 0.85 (mg/m 2 ) 74 % PAP2.5K>CMC90K>PAP10K>CMC700K>PSS70K>PSS1M (Kim et al. ES&T 2009, 43(10), )