Biotech and Biochemical Applications

The biotechnology industry, which originated in the late 1970s, has become one of the emerging industry that draws the attention of the world, especially with the emergence of the genetic engineering as a means of producing medically important proteins, during the 1980s. Two of the major interest applications of membrane technology in the biotechnology industry will be the separation & purification of the biochemical product, as often known as Downstream Processing; and the membrane bioreactor, which developed for the transformation of certain substrates by enzymes (i.e. biological catalysts).

Downstream Processing

"Downstream Processing", a new key term given a decades ago, devotes towards the science and engineering principles in separation and purification in this emerging industry, has become a key issue to enhance the quality of the biochemical product. It is particularly important because it typically accounts for nearly three-fourths of the manufacturing costs in this new industry and because reliable and effective purification can be of the utmost important to the user. Membrane separation, together with the bioaffinity chromatography, liquid extraction and selective precipitation are the few techniques in the bio-separations, which gain attention from both the industries and researcher in order to upgrade the product quality of the biochemical industry.

Lots of study has been put in this area involving the most of the recovery of the biofuels and the biochemicals. Throughout the available literature, the most useful review is presented by Stephen A Leeper (1992), which compiles a large number of the previous and current studies' data on the different types of biofuels and the biochemicals product recovery, consisting of the usage of different types of membrane materials, membrane processes, together with the operating parameters of the studies being carried out.

Membrane Bioreactors

Since its introduction in the 1970s, membrane bioreactor has granted a lot of attention over the other conventional production processes is the possibility of a high enzyme density and hence high space-time yields. Whereas downstream processing is usually based on discontinuously operated microfiltration, membrane bioreactor are operated continuously and are equipped with UF membranes. Two type of bioreactor designs are possible: dissolved enzymes, (as in used with the production of L-alanine from pyrurate) or immobilized enzymes membrane.

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Future Prospects

Membrane science began emerging as an independent technology only in the mid-1070s, and its engineering concepts still are being defined. Many developments that initially evolved from government-sponsored fundamental studies are now successfully gaining the interest of the industries as membrane separation has emerged as a feasible technology.

As were noted by the US National Research Council, the technological frontiers of the membrane technology should be concerned more in the developing of new membrane materials and the identification of new ways of using permselective membranes.

New membrane materials to be used is still a big option in the research of this brand new technology, as most of the researchers are always intend to get a better improvement for this separation process. Journal of Membrane Science serve as a good reference, where lots of the new membrane materials research may be found.

For the latter, membrane-based hybrid system serve as a good example, as it is a combination of conventional unit operations and membrane separation processes, which often results in separation processes that offer significant advantages over the exclusive use of either component process. Such advantages may include more complete separation, reduced energy requirement, lower capital cost, and lower production cost. Two good example of this hybrid system are the RO / evaporator hybrid system to concentrate corn steep water, and a membrane / vapor-recompression hybrid process to recover energy in hot, moist dryer exhaust. Studies has also been carried out and proven that these hybrid system did perform a better of the washwater purification and reuse pilot plant (HUMEF) which has been successful installed in Eindhoven pumping station, the Netherlands.

References

1. Parker, Sybil. P, 1994, McGraw Hill Dictionary of Scientific and Technical Terms, McGraw Hill.
2. Philip A. Schweitzer, 1988, Handbook of Separation Technique for Chemical Engineers, 2^nd Edition, McGraw Hill.
3. Douglas M. Ruthven, 1997, Encyclopedia of Separation Technology, John Wiley & Sons.
4. Jacqueline I. Kroschwitz, 1991, Concise: Encyclopedia of Polymer Science and Engineering, John Wiley & Sons.
5. Howley, Gessner G., 1977, The Condensed Chemical Dictionary, 9^th Edition, Van Nostrand Reinhold Company. , 7^th Edition, Volume IX, Clarendon Press Oxford, 1989.
6. The Oxford English Dictionary
7. Green, Perry, 1997, Perry’s Chemical Engineers’ Handbook, 7^th Edition, McGraw Hill,. [Section 22-37 – 22-69]
8. National Research Council (US), 1989, Frontiers in Chemical Engineering: Research Needs and Opportunities,.Washington DC: National Avademy.
9. Cabasso, Gulf South Israel Research Institute.
10. Fauzi I., Ghazali N., Rosli Y., 1998, A Short Course of Membrane Technology, CEPP, University Technology Malaysia.
11. R. Rautenbach, R. Albrecht, 1989, Membrane Processes, John Wiley & Sons. , Hungarian Chemical Society. 1996, University of Indonesia.
12. Proceeding for the 7^th World Filtration Congress Budapest, Hungary 1996
13. Proceeding of the Regional Symposium of Chemical Engineer,
14. R. E. Kesting / A. K. Fritzsche, 1993, Polymeric Gas Separation Membranes, John Wiley & Sons.
15. Ralph E. W., Peter N. P. (Eds), 1986, Industrial Membrane Processes, AIChE Symposium Series (No. 248, Vol82), AIChE.
16. Peter A. (Ed), 1998, World Water and Environmental Engineering, Vol.21, Issue 3, March 1998.
17. Kamalesh K. S., Douglas R. L., 1988, New Membrane Materials and Processes for Separation, AIChE. IChemE Symposium Series, 1978, IChemE.
18. Alternatives to Distillation,
19. Reynolds, Richard, 1996, Unit Operations and Processes in Environmental Engineering, PWS Publishing Company.
20. Hamdani S., Membrane Technology: The Right Choice for ASEAN, UTM.
21. Roger G. H. (Ed), 1994, Protein Purification Process Engineering, Marcel Dekker.
22. Gomez-Fernandez J., D. Chapman, L. Packer, 1991, Progress in Membrane Biotechnology, Birkhauser.
23. David S. Soane (Ed), 1992, Polymer Applications for Biotechnology: Macromolecular Separation and Identification, Prentice-Hall.
24. G. Street, 1994, Highly Selective Separations in Biotechnology, Blackie Academic & Professional.
25. Jean-Francois. H., Jean H., Subhas S., 1990, Downstream Processing and Bioseparation: Recovery and Purifucation of Biological Product, American Chemical Society.
26. Norman L., Joseph C., 1992, Separation and Purification Technology, Marcel Dekker.
27. M.S. Verrall and M. J. Hudson, 1987, Separations for Biotechnology, Ellis Horwood Limited.
28. Munir Cheryan, 1989, Ultrafiltration in Food and Bioprocessing, University of Illinois.
29. W. E. L. Spiess, H. Schubert, Engineering and Food - Advanced Processes, Vol. 3, Elsevier Applied Science.
30. J. Krijgsman, 1992, Product Recovery in Bioprocess Technology, Butterworth-Heinemann.
31. J. D. Stowell, P. J. Bailey, D. J. Winstonley (Eds.), 1986, Bioactive Microbial Product 3: Downstream Processing, Academic Press.
32. J. P. Hamel, Jean B. Hunter, Subhas K. Sikdar (Eds.), 1990, Downstream Processing and Bioseparations: Recovery and Purification of Biological Products, American Chemical Society.
33. http://www.aces.uiuc.edu/~fshn/faculty/cheryan.html [under Research]
34. http://www.dupont.com/
    

**This article was graciously submitted to www.cheresources.com for publication by Foo Chwan Yee from Malaysia. The author can be reached for questions/comments at cyfoo98"at"pd.jaring.my