Preparation of Ti–Fe based hydrogen storage alloy by SOM method

Influence of oxygen introduced in TiFe-based hydride forming alloy on its morphology, structural and hydrogen sorption properties

“…[1] (plateau midpoints for mono-and dihydride) were found to be DH 0 ¼ À28.02 and À34.09 kJ/mol H 2 ; DS 0 ¼ À99.24 and À124.08 J/(mole H 2 K), for the mono-and dihydride, respectively, which is quite close to the literature data: DH 0 ¼ À28. 13 and À33.42 kJ/mol H 2 ; DS 0 ¼ À106.1 and À130.21 J/(mole H 2 K). The calculated parameters for the arc-melted TiFe (Table 2) show good correspondence with the literature data only for the monohydride (segment 2), while for the dihydride (segment 3) underestimations of the absolute values of DH 0 and DS 0 took place.…”

“…The TiFebased hydrogen storage alloys can be prepared by various methods, based on melting the constituents [1e3], their mechanical alloying [4e6], or sintering [7e9]. Other potentially beneficial methods of TiFe preparation include direct reduction of cheap and available ilmenite, TiFeO 3 , by the usage of metal-thermic routes [10], sometimes in combination with the reduction in gaseous H 2 [11]; or electrochemically [12,13]. At the same time, the hydrogen sorption performances of TiFe-based alloys are quite sensitive to the preparation conditions that could result in variations of stoichiometry of the parent intermetallic compound, inhomogeneities and/or introducing impurities, especially, oxygen.…”

Clean Metals Production by Solid Oxide Membrane Electrolysis Process

“…• another metal if an alloy with that metal is desired (e.g., Si or Nd is produced on an iron cathode to form Fe-Si or Fe-Nd alloy, respectively), • another metal from which the desired metal can be crystallized out in a pure form (e.g., Si crystallized from a liquid Sn cathode) [34,52], or • the oxide of the desired metal in the form of a compressed pellet (e.g., Ta, CeNi 5 , Ti-Si, Ti-Fe) [20,31,35,36,39].…”

“…This SOM cell design not only has all the advantages of the FFC Cambridge process but also allows the application of a high applied potential (3.5 V) without dissociating the CaCl 2 salt, which is a great advantage in terms of getting higher current densities. Similar SOM cell design has also been used to produce various refractory metals and alloys including Nb, Cr, Ti, Ti-Fe alloy, Ti-Si alloy [36][37][38][39].…”

“…A decade ago, Pal's pioneering work on new molten salt compositions increased solubility of many oxides, e.g., CaF 2 -MgF 2 eutectic molten salt dissolves *10 wt% MgO, decreased zirconia corrosion rate, and has generated new interest in commercialization of the process for metals production [19,20]. The SOM process has been applied to reduce various metal oxides or oxide compounds to the respective metals or alloys, including Mg [19,[21][22][23][24][25][26], Al [27], Ti [28], Ca [29,30], Fe [22], Cu [31], Ta [20], Cr [20], Nb [20,32], Yb [33], Nd, Pr, Dy, Si [34], CeNi 5 , and La x Ce 1-x Ni 5 [35], Ti-Fe alloy [36,37], Ti-Si intermetallics [38,39]. A series of the metals produced by the SOM process are highlighted in the periodic table presented in Fig.…”