Hydrogen permeability for

V-Ti-Ni alloys and Fe- /Co-Based metallic glasses have been evaluated with respect to hydrogen permeability for potential use in hydrogen purification membrane reactor application. Microstructural characterization of the V-Ti-Ni alloy using SEM has shown similar microstructural features to a previously evaluated Nb-Ti-Ni alloy namely, the occurrence of a primary phase surrounded by interdendritic eutectic. 

Hydrogen permeability for several alloys as a function of temperature the solid lines represent the range of temperature over which the measurements were made, and the dotted lines are extrapolations of exponential form to room temperature (298 K). The austenitic Fe is an average relationship for a number of austenitic stainless steels [18] the low-alloy Fe alloy is quench and tempered 4130 [191 the non-ferrous alloys are all pure metals Ni [20] Al [21] Cu and Au [22]. Measurements made in hydrogen isotopes were corrected to hydrogen using classical rate theory [17]. 

Table 8.1 Measured values of hydrogen permeability for membranes based on group IVB-VB elements...

Figure 4.7 Hydrogen permeability for a modified porous glass support as a function of temperature and time of deposition (Prabhu Oyama, 2000).

Table I. Hydrogen permeability for Palladium containing materials.

Dense ceramic ion High selectivity for hydrogen Low permeability for hydrogen Laboratory scale... 

Some hydrogenation techniques may induce surface damage that increases the H concentration at the surface. Some of the compounds tend to decompose during hydrogenation for example, the surface of InP decomposes with the formation of phosphine (PH3). This problem has been controlled by encapsulating the substrate with a hydrogen-permeable layer. 

Properties Density Thickness Electrical Resistivity Corrosion Current Permeability for Hydrogen Modulus of Elasticity... 

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