Removal of nitrogen and methane from hydrogen by metal getters

Measurements of the purification of hydrogen from nitrogen and methane impurities using the getters Zr3A12 and Zr(V0/sub.83Fe0/sub.17)2 have been carried out. It was found that both getters remove nitrogen as well as methane from a flow of hydrogen more effectively with increasing temperature. A depletion of nitrogen by a factor of approx. =103 was observed; a result which is similar to that found earlier for the depletion of CO impurities. In contrast to the effectiveness of the getters on N2, CO and O2 imputities a measurable depletion of CH4 required temperatures in excess of 5000C. Appreciable depletion of CH4 occurs at about 6000C by the use of both getters; the underlying processes, however, are not clear. In addition to measurements on the depletion of impurities in hydrogen relative pumping speeds for D2,N2 and CH4 for both getters were determined. The pumping speed for CH4 at 5100C e.g. was found to be a factor of 10 lower than that for N2