1. 1 Movie of CO 2 and H 2 Permeation Movie courtesy of Josh Chamot, NSF: http://www.nsf.gov/news/news_summ.jsp?cntn_id=105797&org=NSF

2. 2 Membrane Hydrogen Purification: Classic H 2 /hydrocarbon separation H 2 /CO ratio adjustment NH 3 purge gas recovery Photo from Air Liquide

3. 3 Steam reforming of hydrocarbons accounts for 95% of the hydrogen produced in the U.S. (DOE 2003): U.S. H 2 production was 810 million kg/yr in 2003. (DOE) –Growth due to: Low grade crude in refineries Power source for fuel cells DOE = http://www.eere.energy.gov/hydrogenandfuelcells/ Fuel Cell Facility (PLUG) PLUG = http://www.plugpower.com/technology/overview.cfm Membranes may be useful for purifying H 2 : - Low capital costs - Compact size - Ease of operation Interest in Hydrogen

4. 4 Air Liquide Slides courtesy of Dr. Greg Fleming, UT Ph.D. ‘87

5. 5

6. 6 Air Products Slide courtesy of Dr. Lloyd Robeson

7. 7

8. 8 Fuel Cell Operation From Jim McGrath, Virginia Tech Source: H Power

9. 9 Just what the environment needs from a car. Water. Hydrogen powered Fuel Cell vehicles only emit water. From Jim McGrath, Virginia Tech

10. 10 H2 Purity Requirements for Fuel Cells A National Vision of America’s Transition to a Hydrogen Economy - 2030 and Beyond, U.S. DOE, 2/2002.

11. 11 Cost Estimates for H 2 Production http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/vision_doc.pdf

12. 12 FutureGen "Today I am pleased to announce that the United States will sponsor a $1 billion, 10-year demonstration project to create the world's first coal-based, zero-emissions electricity and hydrogen power plant..." President George W. Bush February 27, 2003

13. 13 FutureGen Concept

14. 14 Current applications: Air separation - mainly N 2 enriched air Natural gas treatment - acid gas removal H 2 separation - H 2 from hydrocarbons, ammonia purge, syngas Removal of vapors from mixtures with light gases (vapor separation) Advantages: Low energy separation (no phase change) Reliable (no moving parts) Small footprint Drawbacks: Incomplete separation (need higher selectivity) Low chemical/thermal stability (need more resistant matls.) Gas Separations Using Membranes

15. 15 High flux (high permeability, thin) High selectivity Tolerance to all feed components Mechanical stability Ability to be packaged in high surface area modules Excellent manufacturing reproducibility, low cost Ideal Membrane Characteristics

16. 16 D. Wang, et al., ACS Symp. Ser., v. 744, p. 107, 1999. ~5,000 m 2 /m 3 Contaminated Natural Gas (High Pressure) CO 2 - rich permeate (Low pressure) Upgraded Natural gas (High Pressure) Hollow Fiber Module

17. 17 Amine Scrubber Membrane Unit U.S. Pipeline Specifications 1 : Potential membrane applications: Acid gas removal N 2 removal Higher hydrocarbon removal Dehydration 1 R.W. Baker, I.&E.C. Res., 41, 1393 (2002). Natural Gas Purification

18. 18 J. Membr. Sci., 107, 1-21 (1995) Gas Transport in Polymers: Solution-Diffusion Model

19. 19 PDMS: PSF: Characteristic Polymer Permeation Properties

20. 20 B.D. Freeman and I. Pinnau, "Polymeric Materials for Gas Separations," in Polymeric Membranes for Gas and Vapor Separations: Chemistry and Materials Science, Edited by B.D. Freeman and I. Pinnau, ACS Symp. Ser. 733, pp. 1-27 (1999). Solubility and Diffusivity Characteristics

21. 21 Traditional membrane materials Glassy polymers Designed to be strongly size-sieving Low permeability High selectivity due to high diffusion selectivity Upon plasticization, selectivity decreases, sometimes strongly H 2 selective in H 2 /CO 2 separations Our approach Rubbery polymers Designed to be strongly solubility-selective High permeability Selectivity derives primarily from high solubility selectivity Upon plasticization, separation properties can increase in some cases (CO 2 /H 2 ) Materials Design Approach

22. THF ACN Effect of Polar Groups in Liquid Solvents on CO 2 Solubility and CO 2 /N 2 Solubility Selectivity Lin and Freeman, J. Molecular Structure, 739(1-3), 57-74 (2005).

23. R=CH 3 ; poly(ethylene glycol) methyl ether acrylate (PEGMEA); n=8 R=H; poly(ethylene glycol) acrylate (PEGA); n=7 Poly(ethylene oxide) diacrylate (PEGDA: Crosslinker) UV n 14 ][ O CH 2 2 O O C 2 C O 2 2 C O O 2 2 OROR [] Crosslinked Poly(ethylene oxide) [XLPEGDA]

24. Mixed Gas Separation Lin, Haiqing, E. van Wagner, B.D. Freeman, L.G. Toy, and R.P. Gupta, “Plasticization- Enhanced H 2 Purification Using Polymeric Membranes,” Science, 311(5761), 639-642 (2006).

25. Mixed Gas CO 2 /CH 4 Separation PEGDA (crosslinker; 30wt %) CH 2 C O O 2 2 OCH 3 []8]8 PEGMEA (monomer: 70 wt%) ] 13 [ O CH 2 2 O O C 2 C O 2 Lin, Haiqing, E. van Wagner, B.D. Freeman, and I. Roman, “High Performance Polymer Membranes for Natural Gas Sweetening,” Advanced Materials, 18, 39-44 (2006).

26. 26 THANK YOU!