Nano -porous membanes in Gas Processing

1. By Chris Heflin Rachael Houk Mike Jones Nano-porous membanes in Gas Processing A theoretical analysis of non-chemical separation of hydrogen sulfide from methane by nano-porous membranes using capillary condensations from Chemical Engineering and Processing

2. Natural Gas as it comes out of ground needs to have H2S removed before further processing • Starting levels can be high (>5%) • For US pipelines, limit is 4 ppm • Traditionally done through chemical means • One alternative is to use a nano-porous membrane to achieve a physical separation Introduction Image Source: http://chemistry.about.com/od/factsstructures/ig/Chemical-Structures---H/Hydrogen-Sulfide.htm

3. Traditional methods • Wash with MEA, DEA, or other amines • Use an oxide adsorbent • Disadvantages • Consumes these chemicals • Added hazards due to additional chemical at site Conventional H2s separation

4. Removes H2S, CO2, and mercaptans Need a lot of equipment Need both heating and cooling utilities Amine Wash Separation Image from http://en.wikipedia.org/wiki/Amine_gas_treating

5. Excellent separation achieved Can have significant pressure drop Need high temperatures Use iron oxide or zinc oxide Oxide Adsorbent Image from http://www.cwaller.de/sorbents.htm

6. Good selectivity in allowing H2S through and not CH4, only a small amount of CH4 dissolved in liquid H2S phase Minimal pressure drop in bulk phase Criteria for a good Membrane

7. Bulk Phase Permeate Mechanism Nano-porous membrane CH4 H2S H2S CH4 CH4 CH4 H2S H2S CH4 FLOW CH4 Not to scale

8. Nano-porouos membranes Images from www.mdpi.com/1996-1944/3/1/165/ag sites.google.com/.../home/MAIN_NANO_2.jpg www3.interscience.wiley.com/.../ncontent

9. Temperature Vs Permeability

10. Where x = mole fraction in the pore y= mole fraction in the bulk Separation factor

11. Temperature vs separation

12. So, How Are Nanoporous Membranes Made?

13. A schematic diagram showing pore formation by electrochemical self-ordering • Scheme of electrochemical cell for anodization and corresponding electrochemical reactions. • Scheme of pore formation, which includes several steps: • the formation of oxide layer on metal surface; • local field distributions caused by surface fluctuations; • the initiation of pore growth by field-enhanced dissolution; and • the pore growth in steady-state condition • Typical current density curve obtained with anodization showing these stages Self-Ordering Electrochemical Process

14. New development by Dr. DucasLosic of the University of South Australia A series of fabrication protocols to precisely control their most critical parameters, including pore diameters, pore geometry and surface chemistry cyclic anodization

15. H2S separation is necessary: traditional methods are ok, but nano-porous membranes could do better The H2S condenses and flows through the membrane to separate; this depends on temperature and pressure Membranes can be made through self-ordering electrochemical process and cyclic anodazition Conclusion

16. Gas mixtures of more than just methane and hydrogen sulfide, like actual natural gas Optimized temperature and pressure Better manufacturing techniques, particularly for large scale production Try a pilot plant scale testing Further Research

17. http://en.wikipedia.org/wiki/Amine_gas_treating http://www.chem.tamu.edu/class/majors/chem470/Synthesis_Gas.html http://www.thefuelman.com/Documents/H2S_removal.pdf http://en.wikipedia.org/wiki/Hydrogen_sulfide “Engineering of Nanomembranes for Emerging Applications” by Dr. DucasLosichttp://www.azonano.com/details.asp?ArticleId=2445 “Simple and reliable technology for manufacturing metal-composite nanomembranes with giant aspect ratio” by Jovan Matovića and ZoranJakšićhttp://www.sciencedirect.com “Self-ordered nanopore and nanotube platforms for drug delivery applications” by DusanLosic & SpomenkaSimovichttp://informahealthcare.com/doi/pdf/10.1517/17425240903300857?cookieSet=1 References

18. Group S2 rebuttal Chris Heflin Rachael Houk Mike Jones

19. Data used showed amine needed to be replaced slowly with a fresh stream because some of it leaves in the tail gas stream • No info available on the cost of the nano-porous membrane to compare with traditional methods • The presentation was right after Dr. Seminario did a harsh critique of a previous presentation, so there was reason to be nervous, but we should have rehearsed more.

20. Thanks for the feedback on the animation and introduction. We’ll try to continue this practice in our future presentations.

21. Group S1 Review of Nano Membranes for Gas Separation Group S1

22. Notes on Presentation Positive Notes Opportunities for Improvement Presentation was very short Could have included more information and spent more time on use and applications Lasted less than 15 minutes More eye contact during presentation Cite sources on slides Could not have known due to guidelines being presented right before • Good at answering questions • Separation animation was helpful • Summary of chemical method was thorough and educational • Good analysis of research and future development needs Group S1

23. Grade • Slides (20/20) • Informative, well designed • Oral presentation (19/20) • Good skills but needed more eye contact • Graphics (18/20) • Needed a few more pictures and diagrams • Educational Value (20/20) • Topic was well explained • Group Analysis of Research (19/20) • Needed a little more research on topic for thoroughness • Overall (96/100) Group S1

24. Group S3Review: nanoporous membranes Group S3: Michael Koetting Bradford Lamb James Kancewick

25. Review • The presentation was informative and the slides were generally well done. • Student questions were answered confidently and in detail. • Presentation was not too detailed to be understandable by the audience, yet still detailed.

26. Review • Speaking could have been more polished, with more eye contact from some of the speakers and less reading from slides/notes. • Some figures in the slideshow were not explained, so they added very little to the presentation. • Despite this, however, the presentation was very good on the whole.

27. Group S4 Review of Nano Membranes for Gas Separation Scott Marwil Danielle Miller Joshua Moreno Group S4

28. Things Done Well • Very good job with the illustrations and the animations • The group did a good job of answering the classes questions in a full and in-depth manner • The group members presenting knew the material and did an good job relaying that knowledge onto the rest of the class • The Group was very well spoken • They made good use of animations and pictures to illustrate points • Their introduction was very thorough and well written • The material was presented in an interesting and exciting way Group S4

29. Things That Need Improvement • The overall presentation was a little on the short side. • The group needs to develop a better introduction to introduce the topic and background to the class instead of just jumping to the heart of the material so quickly • Sometimes the slides contained a bit too much information. They should try limit the amount of information on the slides so they can draw attention to the speaker. The Not-So-Good Group S4

30. Group S5 Review of Nano Membranes for Gas Separation PradipRijal Jason Savatsky Trevor Seidel Laura Young Group S5

31. Presentation Review • The groups power presentation and visuals were very well done. • They probably should have practiced the presentation a little more. The oral presentation was weak and unfocused. • Their attire was appropriate for the occasion. Group S5

32. Group S6 Review of Nano Membranes for Gas Separation John Baumhardt Daniel Arnold Michael Trevathan Michael Tran

33. Review • Slide layout was agreeable and pleasant to look at. • The presentation was detailed and well thought out. • The further research section is a little weak (the natural gas composition could have included a sample composition of “actual natural gas” • The presentation overall was quite good, but the presenters seemed a little nervous, and were reading off of the slides.

34. Review of Information • From a natural gas background, the disadvantages listed are not valid. In an amine system, there are no chemicals stored on site because there are very few reasons to change the amine. Apart from wanting to try a more efficient amine, standard amine reclamation (cleaning) can be performed to regenerate the existing amine. • Even without regeneration, amine lasts years in plants without replacement. • We would have liked a cost comparison of the nano-porous membranes vs the traditional amine, to determine the commercial viability of the membranes in gas plants.