Kinetics of permeation and absorption of hydrogen in palladium during bending and unbending of a palladium cantilever

2020 ◽  
Vol 127 (24) ◽  
pp. 245104
Author(s):  
E. P. Feldman ◽  
E. N. Lyubimenko ◽  
K. V. Gumennyk
2021 ◽  
Vol 2057 (1) ◽  
pp. 012043
Author(s):  
I A Romanov ◽  
V I Borzenko ◽  
A N Kazakov

Abstract This work is devoted to an experimental study and comparison of the kinetics of hydrogen absorption by an intermetallic compound LaNi4.4Al0.3Fe0.3 in form of pure intermetallic compound free backfill and a compact based on it obtained by cold pressing with a spiral matrix of nickel-foam. To calculate the kinetic parameters of the hydrogen absorption reaction, the initial rates method is used. The PCT absorption isotherms are measured at temperatures of 313, 333, and 353 K. The experimental data are described with quite high confidence by the chosen model, which assumes that the reaction rate controlling step is the dissociative absorption of hydrogen on the surface of the a-phase. The rate of hydrogen absorption increases with increasing pressure drop and temperature. It is shown that the rate of hydrogen absorption by the sample of pure IMC is significantly less dependent on temperature compared to the compact sample. In addition, the reaction rate at temperatures of 313 and 333 K is higher for the free backfill sample, and at 353 K it is higher for the metal hydride compact. The values of the absorption constant and the activation energy of the hydrogen absorption reaction are determined for both samples.


CORROSION ◽  
1958 ◽  
Vol 14 (12) ◽  
pp. 34-38 ◽  
Author(s):  
T. G. OWE BERG

Abstract The reaction mechanisms for the absorption of hydrogen by metals from moist hydrogen gas and dilute acid solutions, for the desorption from metals of dissolved hydrogen in the presence of water and for hydrogen solubility and permeation under those conditions are discussed. Their kinetics are also given. Formulae are derived for rates and equilibria. These are compared with experimental data. The migration of H atoms in the metal is concluded to be associated with zero or nearly zero activation energy. Diffusion is rapid enough to maintain almost uniform distribution of H atoms in the metal during absorption and desorption under ordinary conditions. 3.8.4


2003 ◽  
Vol 58 (2) ◽  
pp. 417-427 ◽  
Author(s):  
S Ebrahimi ◽  
R Kleerebezem ◽  
M.C.M van Loosdrecht ◽  
J.J Heijnen

MRS Advances ◽  
2020 ◽  
Vol 5 (20) ◽  
pp. 1059-1069
Author(s):  
Ntumba Lobo ◽  
Alicja Klimkowicz ◽  
Akito Takasaki

AbstractMagnesium hydride (MgH2) is a prospective material for the storage of hydrogen in solid materials. It can also be envisaged for thermal energy storage applications since it has the potential to reversibly absorb hydrogen in large quantities, theoretically up to 7.6% by weight. Also, MgH2 is inexpensive, abundant, and environmentally friendly, but it operates at relatively high temperatures, and the kinetics of the hydrogenation process is slow. Mechanical milling and the addition of catalyst can alter the activation energy and the kinetic properties of the MgH2 phase. It is known that the addition of titanium hydride (TiH2) lowers the enthalpy and enhances the absorption of hydrogen from MgH2, titanium oxide (TiO2) enhances the desorption of hydrogen and niobium oxide (Nb2O5) enhances the absorption of hydrogen. In this work, the influences of the catalysts, as mentioned above on the properties of MgH2, were studied. The samples were analyzed in terms of crystal and microstructure as well as hydrogen storage properties using a pressure-composition isotherm (PCT)measurement. It has been found that the simultaneous addition of the three catalysts enhances the properties of MgH2, lowers the activation energy and operating temperature, increases the rate of intake and release of hydrogen, and provides the largest gravimetric hydrogen storage capacity.


2005 ◽  
Vol 884 ◽  
Author(s):  
Xia Tang ◽  
Daniel A Mosher ◽  
Donald L Anton

AbstractSodium alanate has been studied as a promising candidate material for reversible hydrogen storage due to its intermediate temperature range and relatively high storage capacity. Its rates of desorption and absorption of hydrogen have been shown to be enhanced by the addition of Ti in various compounds. To date, the sorption kinetics, especially absorption kinetics, is not well understood. In this study, a practical sorption kinetics model for TiCl3 catalyzed NaAlH4 has been developed to assist in the engineering design and evaluation of a prototype hydrogen storage system.


1997 ◽  
Vol 14 (5) ◽  
pp. 307-311 ◽  
Author(s):  
Satoru Asai ◽  
Hidemi Nakamura ◽  
Yasuhiro Konishi

CORROSION ◽  
1960 ◽  
Vol 16 (4) ◽  
pp. 198t-200t ◽  
Author(s):  
T. G. OWE BERG

Abstract The kinetics of absorption of hydrogen in corrosion is treated on the basis of a mechanism previously proposed for the absorption of hydrogen from H2 gas. Rate formulae are derived and compared with experimental data. On certain simple assumptions, a parabolic or a cubic rate law is derived for an initial period, during which absorption of hydrogen occurs. This rate law is succeeded by a linear rate law when the metal is saturated with hydrogen. The rate in acid solutions is proportional to the square root or the cube root of the acid concentration. The rate in water vapor is proportional to the square root of the water vapor pressure or independent of the water vapor pressure. 3.8.4


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