Vanadium hydrogen permeable membranes

In the patent by Hill, an aUoy of titanium containing 13 wt%vanadium, 11 wt% chromium and 3 wt% aluminum was developed as a hydrogen transport membrane material [12]. In this alloy, the crystal structure of titanium, which is normally hexagonal below 1153 K (880 °C), is stabilized in its high-temperature body centered cubic allotropic form. The body centered cubic crystal lattice is preferred for hydrogen transport. This titanium alloy was found to have hydrogen permeability superior to that of pure palladium in the range 300-450 °C (573-723 K)... 

In fact, although, niobium (Nb), vanadium (V) and tantalum (Ta) offer higher hydrogen permeability than palladium in a temperature range between 0 and 700°C, as shown in Fig. 2.8, nevertheless these metals give a stronger surface resistance to hydrogen transport than the palladium (Pd). For this reason, dense palladium membranes are preferentially used. 

Other studies of vanadium alloys have been carried out on membranes consisting ofV-15%Ni covered by thin layers of Pd. °" Ozakicffl/. focused their work on the V-Ni-Al alloy which exhibited hydrogen permeability... 

Iodide ion-selective electrode The iodide electrode has broad application both in the direct determination of iodide ions present in various media as well as for the determination of iodide in various compounds. It is, for example, important in the determination of iodide in milk [44,64,218, 382, 442], This electrode responds to Hg ions [150, 306, 439] and can be used for the indirect determination of oxidizing agents that react with iodide, such as 10 [305], lOi [158], Pd(II) [117, 347,405] and for the determination of the overall oxidant content, for example in the atmosphere [393], It can also be used to monitor the iodide concentration formed during the reactions of iodide with hydrogen peroxide or perborate, catalyzed by molybdenum, tungsten or vanadium ions, permitting determination of traces of these metals [12,192,193, 194, 195]. The permeability of bilayer lipid membranes for iodide can be measured using an I"... 

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