By Paul Edmiston, College of Wooster

1. New Tools in the Water Technology Toolbox
Swellable Organosilica Materials for
Reversible Extractions of Dissolved Organics
and Metals
Paul L. Edmiston
College of Wooster
Contact Information:
pedmiston@wooster.edu
ACS Fall Meeting 2012, Philadelphia, PA
Ensuring the Sustainability of Critical Materials and Alternatives

2. High Volume Waste Streams, Very Little Attention
“The solution to pollution
is dilution.”
When something outlasts a certain degree of usefulness, we
wish it to disappear. Since matter cannot be destroyed, a
convenient disposal method is dilution.
Two high volume waste streams that are hard to dilute due
to volume, but may hold great resource potential:
1. Produced Water
2. Stormwater Runoff

3. Produced Water: Energy-Water Nexus
Produced water is the water from petroleum production.
800 billion gallons of produced water every year.
Current practice onshore: Reinjection
Current Practice off-shore: Overboard
Average 10 water: 1 oil ratio
Produced water contains:
dissolved organics production chemicals NORMS
organic acids metals ions salt

4. Oil Sand Production: Energy-Water Nexus
Steam assisted gravity drain (SAGD) water
300 million gallons per day by 2030.

5. How much organic in produced water?
Just considering dissolved hydrocarbon and BTEX ~ 250 ppm
250 ppm x 800 billion gallons = 250 million gal of gasoline eq.
Enough gasoline to supply U.S. needs for 1 day.*
*U.S. Energy Administration http://www.eia.gov/tools/faqs/faq.cfm?id=23&t=10

6. How much organic in produced water?
Just considering dissolved hydrocarbon and BTEX ~ 250 ppm
250 ppm x 800 billion gallons = 250 million gal of gasoline eq.
Enough gasoline to supply U.S. needs for 1 day.*
Extraction of dissolved
components has a substantial
thermodynamic barrier.
Need to overcome entropy.
*U.S. Energy Administration http://www.eia.gov/tools/faqs/faq.cfm?id=23&t=10

8. Aryl-Bridged Mesoporous Silica That Swells: Osorb®
No solvent 150 µm
200 nm
+Solvent
OCH3
H3 CO Si CH2CH2 OCH3
OCH3 CH2 CH2 Si OCH3
OCH3
Surface area: 400-600 m2/g
Pore volume: 0.6-1.5 mL/g

9. Sol-Gel Derived Mesoporous Silicas
Sol-Gel Process Ordered Templated Materials
Aerogels
Polysilsesquioxanes

10. Origin of Swelling Behavior
Flexibly tethered array of silica nanoparticles
Dry Partially Swollen Fully Swollen
200 nm 150 nm
200 nm
Gelation Crosslink Derivatize/Dry

11. Characteristics of Osorb
1200
Volume Adsorbed cc/g (STP)
1000
800
600
400
200
0
0 0.5 1
Relative Pressure Ps/Po
®
Surface Area and Pore Volumes of Various Osorb Materials
Swell Surface Pore Pore Size Distribution (%)
2
Type mL/g Area(m /g) Volume (mL/g) under 6 nm 6-8 nm 20-80 nm
1 5.2 885 2.85 6 8 68
2 9.8 416 0.57 48 22 -
3 4.6 171 0.27 98 - -
4 2.5 803 0.98 20 15 38

12. Force Generation Upon Swelling
Organic liquids Hydrocarbon vapors
propane
600
liquid = acetone
500
Force N/g
400
300
200
methane
100
0
0 1 2 3 4
Volume increase (v/v)
Max force 600 N/g (61,000 w/w)
Work = 0.8 ± 0.1 J/g
ΔHswell = 5.2 ± 1.2 J/g
Entropically driven process Max 1x w/w change for condensable
300% ΔV, 650% Δmass vapors when p=p0 13% volume,

13. P ro d u c e d Wa te r Tre a tm e n t
Os o rb ® re m o ve s a wid e ra n g e o f o rg a n ic s fro m wa te r:

14. Absorption Model
hydrophobic
barrier
1 Matrix tension 2
void volume
new surface area
Dissolved hydrocarbons
3 4
Continued matrix expansion

15. Absorption Model: Solid Solvent
Extra c tio n o f 30 Co m p o u n d s
Os o rb ® a c ts a s a “s o lid s o lve n t” th a t u s e s b y Os o rb vs . lo g Ko w
m e c h a n ic a l re la xa tio n a s a n a d d itio n a l d rivin g
fo rc e fo r a b s o rp tio n o f o rg a n ic s fro m wa te r.
Expansion is endothermic indicating a decrease in
entropy (∆Smatrix) that is a significant energy term
manifested by fact that swelling can produce
mechanical forces that exceed 400N/g.
In g e n e ra l, th e re is a o n e o rd e r o f m a g n itu d e
g re a te r p a rtitio n c o e ffic ie n t fo r a b s o rp tio n b y
Os o rb c o m p a re d to liq u id -liq uid e xtra c tio n d u e k = Osorb/water equilibrium partition coefficient
to th e c o n trib u tio n fro m m a trix e xp a n s io n . Kow = octanol-water partition coefficient
Conditions : contaminant concentration 100 ppm, 0.5%
w/v Osorb per volume of solution, T=25°C.

16. Treatment of Highly Impacted Water
Pesticide waste Flow back water
Complex mixture of pesticides, dyes, TOC before = 265 ppm
BTEX, surfactants TOC after = no detect
(5% organics by weight) 0.4%w/v Osorb

17. Rare Earth Extraction from Shale Gas Water
Rare earths elements are not
rare, but formations of high
concentration are hard to find.
Found in alluvial deposits where
freshwater meets salt water.
Ideal location would be in ancient
estuary environments.
Many are buried in shale
deposits.
Hydraulic fracking is exploring
deep shale deposits.
Utica shale shows regions where rare earth element concentrations
are in excess of 4,000 ppm.
Exploring synergistic extraction of REEs and hydrocarbons in PW

18. Rare Earth Extraction from Shale Gas Water
Challenge is extracting REE
from Group II cations.
Creating a type of Osorb that
duplicates the multistage
liquid-liquid extraction process
use in conventional
hydrometallurgical processes
in a single core-shell particle
Goals:
1) Rapid sampling system
using hand-held XRF
2) Larger scale extraction
system for PW.

19. Ex situ remediation: Produced water and flow back
Funding from National Science Foundation and U.S. Department of Energy
for pilot scale testing in the field, produced water and flow back
Trailer and Skid-Mounted Systems Available (4-60 gal/min)
Skid system tested by Texas A&M University

20. Stormwater Runoff Problem

21. Stormwater Runoff Problem

22. What critical materials are being lost?
Nitrate and Phosphate
55% of the energy input in domestic
wheat production is nitrate fertilizer
Economical supplies of phosphate are
Woods J et al. Phil. Trans. R. Soc. B 2010;365:2991-3006 limited and can be depleted.

23. Rain Garden/Bioswale/Bioretention
Designed to slow the flow of stormwater and filter pollutants from
the water before it eventually recharges ground water, seeps into
the municipal storm sewer system, or discharge into waterways
 Rain Garden, Bioswale, Bioretention System, Bioinfiltration
System, Biofilter, Stormwater Wetland, Vegetated Buffer System

24. Rain Garden/Bioswale/Bioretention
 Multiple physical, chemical, and biological functions
 Limited adsorption capacity:
- Short retention time
- Poor removal of soluble pollutants
- Not recommended at “hot spots”

25. Project Goals
 Title: Development of Physico-Chemically and Biologically
Activated Swelling Organosilica-Metal Composites Filter Media
in Bioretention Systems for Enhanced Remediation of Urban
and Agricultural Stormwater Runoff
 Hypothesis: Properly amended Osorb-metal composites filter
media in bioretention systems can remove a wide variety of
stormwater runoff pollutants and significantly enhance overall
treatment capacity of the systems
 Work Plan: Develop Osorb-based materials with embedded
reactive metal particles including aluminum (Al0), iron (Fe0),
magnesium (Mg0), zinc (Zn0), and nickel (Ni0) to capture organic
pollutants and chemically degrade pollutants from runoff water

26. Osorb®-Metal Composites
Al-Osorb Fe-Osorb Mg-Osorb Ni-Osorb Zn-Osorb
- Researched new metal-Osorb composites
- Examined reduction of motor oil, nitrate,
phosphate, atrazine, estradiol, triclosan, and
ethylene glycol
- Continue research to determine reduction
mechanism and longevity in Phase II funding

27. Column Tests:
Osorb®-Metal Composites Fill Media
 Simulated Runoff Pollutants
Parameter Pollutants Concentration (mg/L
Petrolum hydrocarbons Motor oil 1000
1000
Nutrients Nitrate (NO3-N) 20
10
Phosphate (PO4-P) 10
10
Herbicide Atrazine (C8H14ClN5) 1
0.5
Pharmaceuticals 17α-Ethinylestradiol (C20H24O2) 1
0.5
Triclosan (C12H7Cl3O2) 0.5
1
Antifreeze/deicer Ethylene glycol (C2H6O2) 1000
1000
 Experimental Set-Up
 A total of seven simulated runoff event once a week
 Different contents (0%, 1%, 2%) of three Osorb-metals (Fe, Mg, and Zn)
in soil base media: sand or soil mix

28. Iron-Osorb® Bioretention Systems
 OMR001&2 – Iron-Osorb Enviro-Swales (July 2012)
Before After
Before After

29. Field Tests:
Iron-Osorb Enhanced Bioretention System
Site views of field-scale experimental bioretention systems (rain gardens) installed at the campus of the
College of Wooster, OH. One is a standard model, and one version is enhanced with Iron-Osorb.

30. Column Tests:
Motor Oil Removal
 1000 mg/L of motor oil loading
Improved removal efficiency of motor oil with Osorb-Metals

31. Column Tests:
Nitrate Removal
 10 mg/L of NO3-N loading
Up to 50% improved removal efficiency of NO3 with Osorb-Metals

32. Column Tests:
Phosphate Removal
 10 mg/L of PO4-P loading
66 Up to 40% improved removal efficiency of PO4 with Osorb-Metals

33. Column Tests:
Atrazine Removal
 500 µg/L of atrazine loading
Up to 60% improved removal efficiency of atrazine with Osorb-Metals

34. Column Tests:
Hormone Reduction

35. Field Tests:
Nutrient Removal
Lower effluent concentration of nutrients from iron-Osorb
enhanced rain garden compared to standard rain garden

36. Column Tests:
Soil Microbial Community
Scanning electron microscope (SEM) images of soil mix control (a) and Fe-Osorb amended
soil mix (b) in the saturated bioretention design after the completion of 3-month column
experiments. Blue arrows indicate bacteria or other microorganisms.

37. What is Next?
Currently developing a magnetically retrievable
phosphate selective binding Osorb to amend
agricultural bioswales for phosphate recovery and
watershed protection.

38. Philadelphia is taking the lead!
Green City, Clean Waters Plan
Administrator Lisa Jackson and Mayor Michael Nutter announced April 10, 2012 that the EPA
and Philadelphia will join in advancing the use of cutting-edge green infrastructure technologies
to solve the city’s sewage overflows and create healthier neighborhoods for the city’s residents.
The agreement specifically highlights Philadelphia’s capacity to serve as a model for cities
nationwide to embrace green infrastructure to manage stormwater runoff.

39. Acknowledgements and References
Support:
National Science Foundation
U.S. Department of Energy
Ohio EPA
Collaborators:
Dr. Hanbae Yang
Edmiston, P. L.; Underwood, L. A. Absorption of Dissolved Organic
Dr. Tatiana Eliseeva Speciestion a nd P urifica tionOrganically Modified Silica(2009).
S e pa ra
from Water Using
Te chnology 66, 532-540
that Swells.
Dr. Stephen Jolly Burkett, C. M.*; Underwood, L. A.*, Volzer, R. S.*; Baughman, J. A.*;
Justin Keener Edmiston, P. L. Organic-Inorganic Hybrid Materials that Rapidly Swell in
Non-Polar Liquids: Nanoscale Morphology and Swelling Mechanism.
Che mis try of Ma te ria ls 20, 1312-1321 (2008).
Students:
Burkett, C. M.; Edmiston P. L.; Highly Swellable Sol-Gels Prepared by
Zachary Harvey Chemical Modification of Silanol Groups Prior to Drying. J Non-Crys ta lline
S olids ,351 , 3174-3178 (2005).
Alison Chin Edmiston, P.L.; Campbell, D.P.; Gottfried, D.S.; Baughman, J.*; Timmers,
Noel Mellor M.M.* Detection of Trinitrotoluene in the Parts-per-Trillion Range Using
Waveguide Interferometry, S e ns or & Actua tors B. 143, 574-582 (2010).
Christine Kasprisin
Melissa Morgan www.absmaterials.com
Paige Piper pedmiston@wooster.edu 330-234-7999

40. Permeability to Organics vs. Water Vapor
7
Infrared Absorbance in Collection
6
propane
5
Chamber
4
3
2
1
H 2O
8 mm
1 mm 0
0 10 20 30 40 50 60
Time (min)
IR spectrometer
Osorb disk
Gas cell
Vent
(100 mL)
Propane + H2O(g)sat N2, 1 mL/min
Diffusion cell – Osorb separated flow cells