CHARACTERIZATION OF LaNi5-xSnx ? H INTERACTION FOR HYDROGEN PURIFICATION

BORZONE E. M.; MEYER G. O.

San José

Simposio; HYPOTHESIS IX; 2011

HYdrogen-POwer THeoretical and Engineering Solutions International Symposium

AB5 alloys can be tailored to form hydrides in a wide range of pressure and temperature, have fast hydrogen absorption/desorption reaction kinetics at ambient temperature and can resist moderate impure atmosphere without degradation. Though their low gravimetric hydrogen storage capacity relegated them for hydrogen storage, mentioned properties encourage researchers to continue studying the AB5 family for other technical applications such as hydrogen compression, hydrogen purification or hydride based thermal machines. Purification can be achieved by capturing hydrogen from mixed atmospheres during hydriding of the alloy. After this stage, the remaining gas containing the impurities is vented. Then, pure hydrogen is obtained from the hydride decomposition. In this work we present the characterization of LaNi5-xSnx (x  0.5) tailored to fit hydride formation under 1 bar at room temperature. Samples of different composition were prepared by arc melting and activated under hydrogen atmosphere at room temperature. Equilibrium and kinetics properties of the alloy-hydrogen reaction were measured using volumetric techniques in the range of 20-90°C, 0-50 bar. Hundreds of absorption/desorption cycles were performed in a cycling device designed recently in our laboratory. Degradation effects with cycling were measured and analyzed.