Metal hydride foil

A method of chemically synthesizing reduced products including methanol from carbon dioxide and hydrogen has been developed. The method utilizes a metal hydride foil membrane as a continuous source of reactive surface hydrogen atoms and an electrostatic field to enhance the adsorption of carbon dioxide and bicarbonate onto the hydrogen rich surface. The subsequent chemical(rather than electrochemical) reaction between the adsorbed carbon dioxide and surface hydrogen/metal hydride results in the formation of reduced products. 

Moreover, a thorough comparison of the experimental results obtained from foils of metallic hydrides and polymers - both measured under identical experimental conditions - showed that the observed magnitudes of the anomalies are clearly dependent on the physical conditions the hydrogen atoms are involved in [Abdul-Redah 2003], This result contradicts completely the newest theoretical criticism of Ref. [Blostein 2001 Blostein 2003 (b)]. All the results of these tests prove unequivocally that the aforementioned criticism [Blostein 2001 Blostein 2003 (b)] is unjustified in the context of our NCS experiments. 

Figure 3 The characteristic time tncs for Compton scattering on H and D, as function of scattering angle 0, with energy selection by Au-resonance foils. The widths 3.8 and 5.0 A-1 correspond to proton vibrations in a typical metal hydride and water, respectively. The corresponding widths for deuterons are 5.0 and 6.5 A-1, respectively.

Figure 1. (a) Cell arrangement for metal hydride hydrogen insertion reaction. Left side, acid reduction and hydrogen atom incorporation in palladium (Pd) foil membrane. Right side, electrostatic field for enhancement of carbon dioxide/bicarbonate adsorption on foil membrane, (b.) Blow-up of palladium/hydride foil showing hydrogen insertion into carbon dioxide. 

The metal hydride material in these experiments is a 25 micron thick palladium foil ( 99.999 purity, Alfa). The diffusion coefficient of hydrogen through palladium has been measured by electrochemical and g s phase techniques and is approximately 1.6e-7 cm /sec at 20 C (J ). T e exposed palladium membrane surface area is... 

By placing a very pure lithium-metal foil as anode element and a lithium salt in a nonaqueous solution as electrolyte, a new generation of electrochemical generators was bom in the mid-1960s. Basically, the charge transport is identical to nickel-metal hydride (Ni-MH) or nickel-cadmium (Ni-Cd) batteries, except that Li" ions are created by the simple reaction... 

Quite recently Yasumori el al. (43) have reported the results of their studies on the effect that adsorbed acetylene had on the reaction of ethylene hydrogenation on a palladium catalyst. The catalyst was in the form of foil, and the reaction was carried out at 0°C with a hydrogen pressure of 10 mm Hg. The velocity of the reaction studied was high and no poisoning effect was observed, though under the conditions of the experiment the hydride formation could not be excluded. The obstacles for this reaction to proceed could be particularly great, especially where the catalyst is a metal present in a massive form (as foil, wire etc.). The internal strains... 

Hardy and Linnett (59) studied the heterogeneous recombination of atomic hydrogen at room temperature on nickel and nickel alloy foils. They did not find any similarity to the behavior of palladium and its alloys with gold studied earlier (35). There was no evidence that, as a result of exposure to atomic hydrogen, hydride was formed in any metal catalyst investigated with a resulting change in the activity of the initial parent metal catalysts. 

Metal foils used as catalysts in the experiments described above turned out to be ill-fitted to these investigations. The electrolytic transformation of alloy foils into alloy hydrides did not guarantee a sufficient purity of the samples. Copper rich alloys should be excluded from the experiments because they could not be hydrogen treated in the same manner as the other alloys, and consequently no active microcrystalline layer was developed on their surface. 

In the Li-Rh system LiRh is prepared from rhodium metal foil and liq Li in a 25 at% excess of the 1 1 molar ratio. The mixture is heated in an iron crucible to 750-880°C in Ar. The direct reaction of the elements in a molybdenum crucible at 800°C for 7 d produces LiRh. Identical methods produce Lilr and Lilrj with which the rhodium compounds are isostructural . The reaction of Rh metal with LiH at 600°C gives the ternary hydrides Li4RhH4 and Li4RhH5. 

Storage of uranium foil in closed containers in presence of air and water may produce a pyrophoric surface [1], Uranium must be machined in a fume hood because, apart from the radioactivity hazard, the swarf is easily ignited. The massive metal ignites at 600-700°C in air [2]. The finely divided reactive form of uranium produced by pyrolysis of the hydride is pyrophoric [3], while that produced as a slurry by reduction of uranium tetrachloride in dimethoxyethane by potassium-sodium alloy is not [4],... 

Due to the low penetration depth of X-rays in heavy element samples, XRD patterns are not always significant for the structure of the bulk. In analogy to observations made on rare earth metal foils, fee phases observed occasionally after heating and interpreted as high temperature phases of the actinide metals, might be the product of a reaction between the metal surface and residual gas leading, e.g. to hydride etc. 

Hydrides of the bcc group VIA elements Cr and Mo, but not W, are prepared by high-P techniques " . Chromium hydride is synthesized directly from Cr with Hj by keeping a thin Cr foil at 150°C under 2200 MPa for 4 h. The H/Cr atom ratio is 0.93 and the metal lattice structure hep . The hydride, therefore, is equivalent... 

Available forms Structural shapes of all types, plates, rods, wire foil flakes, powder (technical and USP). Aluminum can be electrolytically coated and dyed by the anodizing process (see anodic coating) it can be foamed by incorporating zirconium hydride in molten aluminum, and it is often alloyed with other metals or mechanically combined (fused or bonded) with boron and sapphire fibers or whiskers. Strengths up to 55,000 psi at 500C have been obtained in such composites. A vapor-deposition technique is used to form a tightly adherent coating from 0.2 to 1 mil thick on titanium and steel. 

A possible explanation of these results is that most of the surface of the Pd is contaminated after reduction at 773 K, with only a few sites remaining where H2 can be dissociated and then transferred to sub-surface positions. On a normal, clean Pd surface almost complete monolayer coverage occurs before any sub-surface can be formed because of the depth of the potential well for adsorbed H2 and the activation energy to diffusion. However, it is common knowledge that contaminated Pd wire or foil will not absorb H2 at room temperature, but that mechanical cleaning of the surface allows normal absorption to occur at a rate which is determined by the rate of diffusion of H atoms from surface portholes into the bulk metal. In contrast to the foregoing observations, an Exxon patent claims that Pd/Ti02 in the SMSl states does not form the 3-hydride phase. 

Titanium Basis of the active metals process. May be used as powder or foil prior to braze alloying. Original work by Kelley and Bondley of General Electric. Titanium-bearing brazes wiU wet and flow over ceramic in vacuum, almost as well as solder over cojjier. Frequently applied as the hydride, which dissociates at <800°C, providing nascent hydrogen which tends to scour the... 

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