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An Overview of the Recent Status of Critical and Strategic Metal Production and Development in India
Published in Abhilash, Ata Akcil, Critical and Rare Earth Elements, 2019
B.D. Pandey, Abhilash, Pratima Meshram
Though the use of calcium chloride as a booster is economical, the use of excess (40%) of BeF2 in the reaction mixture yields the best results, which forms a thin coating over MgF2 crystals and rapidly dissolves while ball milled in the presence of water, disintegrating the slag and releasing the beryllium pebbles. The metal pebbles are refined by vacuum induction melting. The vacuum cast ingot is further processed using powder metallurgy (P/M) to produce hot-pressed beryllium blocks, which are precision machined to form various components for space and other related applications. However, for nuclear-grade beryllium, beryllium oxide of high purity is required, which is obtained by processing beryllium hydroxide by beryllate- and carbonate-based processes to produce beryllia of above 99.9% purity.
An electrospray ionization mass spectrometric study of beryllium chloride solutions and complexes with crown ether and cryptand macrocyclic ligands
Published in Journal of Coordination Chemistry, 2020
Onyekachi Raymond, William Henderson, Joseph R. Lane, Penelope J. Brothers, Paul G. Plieger
Another commonly observed feature of the crown ether ligands is their propensity to act as second coordination sphere ligands. Thus, an X-ray structure has shown that the trimeric beryllium hydroxide [Be3(OH)3(H2O)6]3+ can be crystallized alongside 18-crown-6 hydrogen bonded to its water molecules [24]. In this current study, ESI mass spectra reveal dimeric beryllium hydroxido cores such as [LBe2(OH)2]2+m/z 114, [LBeOH(BeO)]+m/z 227, [LBeCl(BeO)]+m/z 245 where L = 12-crown-4. Although the actual structures of such species involving 12-crown-4 are unknown, it is more probable to involve the inner sphere coordination oxido/hydroxido bridging of the two metal centers since under ESI MS conditions the evaporation of the solvent ion will bring the beryllium hydroxido cores in closer coordination proximity with the crown ethers.
Development and potential of composite moderators for elevated temperature nuclear applications
Published in Journal of Asian Ceramic Societies, 2022
Lance L Snead, David Sprouster, Bin Cheng, Nick Brown, Caen Ang, Edward M Duchnowski, Xunxiang Hu, Jason Trelewicz
Beryllium occurs naturally as beryl Be3Al2Si6O18 and chrystoberyl BeAl3O4. Figure 2 provides a high-level representation of how that ore is taken to final product. As depicted, once ore is reduced to the beryllium hydroxide starting material beryllium products may be classified by forming process: powder metallurgy or through melting and ingot metallurgy. As parts cast from ingot tend to have larger grains with low and nonuniform mechanical properties the powder metallurgy process is preferred, with the most common forms of Be being vacuum hot-pressed block.
Extraction equilibrium conditions of beryllium and aluminium from a beryl ore for optimal industrial beryllium compound production
Published in Canadian Metallurgical Quarterly, 2019
Alafara A. Baba, Daud T. Olaoluwa, Ayo F. Balogun, Abdullah S. Ibrahim, Fausat T. Olasinde, Folahan A. Adekola, Malay K. Ghosh
Different approaches were reported to purify the produced beryllium hydroxide precipitate. One approach is to wash the precipitated hydroxide with a solution containing a complexing agent such as EDTA to bring aluminium and other impurities as soluble complexes into solution, leaving pure beryllium hydroxide precipitate [5]. Another approach involves heating beryllium hydroxide with acetic acid to convert it to basic beryllium acetate, which is selectively extracted by chloroform [6,7].