V. A. Polukhin, N. I. Sidorov, E. D. Kurbanova, R. M. Belyakova.
ABSTRACT
The analysis of alloys and methods of their synthesis for membrane technologies for producing ultrapure hydrogen has been carried out. Both traditional Pd-based alloys and alloys based on cheaper metals of V and VIII groups are considered by the example of binary Nb-Ni, V-Ni, Ta-Nb doped with Ti, Zr, Mo, Hf and W. Achievements of kinetic, strength characteristics, thermal stability, wear resistance and stable functionality of membrane amorphous and nanocrystalline alloys with alternative compositions based on Group V elements are considered. The problems of intermetallic hydrogen embrittlement during long-term processes of hydrogen selectivity are considered. A solution to these problems has been proposed by developing new alloys based on Group V and VIII metals alloyed with Ti, Mo, Hf, W; limiting the temperature range from 473 to 673 K; limiting the maximum permissible concentration of hydrogen H/M– less than 0.22. Membrane alloys of solid solutions of Nb (V, Ta)-Ti-Ni compositions with a duplex matrix structure – eutectic phases and primary phases, respectively {BCC- (Nb, Ti) + TiNi} + {Nb (V, Ta), Ti} and NiTi and NiTi2 compounds, which stabilize and protect the matrix structure from brittle fracture. The considered alternative alloys actually make it possible to obtain high-purity gaseous hydrogen using new compositions instead of expensive membranes based on Pd-Au/Ag/Cu alloys.
KEYWORDS
amorphous and nanocrystalline alloys, nickel, titanium, zirconium, niobium, structuring, membrane gas separation, hydrogen purification, solubility, hydrogen permeability, accumulation, thermal stability, fragility, crystallization, modeling, diffusion, nanophases, Me-H hydrides, embrittlement, duplex matrix microstructure.
DOI: 10.31857/S0235010622020050