Palladium membranes applications in reaction systems for hydrogen separation and purification: A review. Palladium–lead alloys for the purification of hydrogen-containing gas mixtures and the separation of hydrogen from them. On the potential of gallium- and indium-based liquid metal membranes for hydrogen separation. Pd-based membranes for hydrogen separation: Review of alloying elements and their influence on membrane properties. Pd based alloy membranes for separation of high purity hydrogen from hydrogen-containing gas mixtures. Hydrogen selective membranes: A review of palladium-based dense metal membranes. The role of palladium in hydrogen economy. The authors declare no conflict of interest. It can lead to the development of pores and microcracks, i.e., degradation of strength characteristics and embrittlement of the materials, which is a fundamental problem in the physics of materials.

Vacancies reduce the charge density near themselves, so they play an important role in the processes of self-diffusion of atoms of metal systems. As is known, a lower energy of vacancy formation leads to a higher concentration of thermodynamically stabilized vacancies in metal systems. In CSR (111) and CSR (311), the additional phase can also have more vacancies, up to 0.10. The larger lattice parameters of the additional phase along the and crystallographic directions, as compared to those along the and crystallographic directions and to parameters of the main phase ( Figure 2a), indicates a higher concentration of lead in this phase. This phase has an almost isotropic distribution in the CSR (hkl). The establishment of peculiarities of hydrogen interaction with metals will contribute to obtaining new potentially important characteristics of membrane filters.įor membrane 1, an additional phase with partially coherent boundaries to the main phase was determined to be of 0.05 ± 0.01 vol.%. The formation and development of deformation processes in metal systems upon the hydrogenation is shown. Specific features of the surface morphology and the structure of the membrane filters depending on the concentration of lead in the alloys are determined. The focus of the study is on the structural state of diffusion filter membranes depending on the content of the palladium-alloying element-lead-and on analysis of the substructure of alloys before and 5300 h relaxation after hydrogenation is carried out. Hydrogenation was carried out from a gas medium at 573 K and the pressure of 16 atm.

Palladium-based membrane filters with lead concentrations of 5 and 20 wt.% were prepared via electric arc melting from high purity metals (99.95%). The importance of this topic is due to the need and demand for improving the performance characteristics of dense metal diffusion filters for high purity hydrogen separation processes. The evolution of a nanostructured state of palladium-lead membrane alloys during their interaction with hydrogen was studied using precision X-ray diffraction with synchrotron radiation (SR) and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDXS).

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