Novel nanostructured media for gas storage and transportation: Clathrate hydrates of methane and hydrogen

In the last years the development of Fuel Cell Technology has highlighted the correlated problem of storage and transport of gaseous fuels, particularly hydrogen and methane.[1] In fact, forecasting a large scale application of the FC technology in the near future, the conventional technologies of storage and transport of gaseous fuels will be inadequate to support an anticipably large request. Therefore many studies are being devoted to the development of novel efficient technologies for gas storage and transport; one of those is methane and hydrogen storage in solid, water-based clathrate hydrates.[2-4] Clathrate hydrates (CH) are non stoichiometric, nanostructured complexes of small 'guest' molecules enclosed into water cages, which tipically form at low temperature-high pressure. In nature, CH's of natural gas represent an unconventional and unexploited energy source. Methane hydrate technology is already applied industrially.[5] More recently, striking literature reports showed a rapid approaching to the possibility of obtaining hydrogen hydrates at room temperature/mild pressure (50 bar).[6-9] Hydrate formation has been shown to be heavily promoted by some chemicals, notably amphiphiles.[4,10-12] Here we show some results on how the chemical properties of several surfactant additives affect the promotion and/or inhibition of clathrate hydrate formation. [1] http://www.eere.energy.gov/RE/hydrogen_transport.html [2] Sloan, E.D. Jr. Clathrate Hydrates of Natural Gases, Second Edition. New York: Marcel Dekker, Inc. 1998. [3] Gudmundsson, J.S., Børrehaug, A., 2nd International Conference on Natural Gas Hydrates, Toulouse, France, June 2-6, 1996. [4] Rogers, R. E., Zhong, Y. (2002), U.S. Patent No.: 6,389,820 May 21, 2002. [5] Kanda, H., Nakamura, K., Suzuki, T. and Uchida, K., 5th International Conference on Natural Gas Hydrates, Trondheim, Norway, June 12-16, 2005 [6] Mao et al., WO 03/037785 [7] Lokshin, K.A. et al., Phys. Rev. Lett. 93, 125503 (2004) [8] Hester, K. C., Koh, C. A., Miller, K. T., Sloan, E. D., Strobel, T. A. and Taylor, C. J., 5th International Conference on Natural Gas Hydrates, Trondheim, Norway, June 12-16, 2005 [9] H. Lee, J. Lee, D. Kim, J. Park, Y. Seo, H. Zeng, I.L. Moudrakovski, C. I. Ratcliffe and J.A. Ripmeester, Nature 434, 743-746 (2005) [10] Savelli, G., Germani, R., Brinchi, L. (2001), in: Reaction and Synthesis in Surfactant Systems, Texter, J. (Ed.), Marcel Dekker, New York, 175-246. [11] Di Profio P., Arca S., Germani R., Savelli G., Chem. Eng. Sci., 60, 4141-4145 (2005) [12] Di Profio P., Arca S., Germani R., Savelli G. 5th International Conference on Natural Gas Hydrates, Trondheim, Norway, June 12-16, 2005