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Beryllium preparation

Hexagonal Crystals of Pure Beryllium prepared by P. Lebeau. [Pg.569]

Beryllium is added to copper to produce an alloy with greatly increased wear resistance it is used for current-carrying springs and non-sparking safety tools. It is also used as a neutron moderator and reflector in nuclear reactors. Much magnesium is used to prepare light nieial allo>s. other uses include the extraction of titanium (p. 370) and in the removal of oxygen and sulphur from steels calcium finds a similar use. [Pg.124]

Beryllium is found in some 30 mineral species, the most important of which are bertrandite, beryl, chrysoberyl, and phenacite. Aquamarine and emerald are precious forms of beryl. Beryl and bertrandite are the most important commercial sources of the element and its compounds. Most of the metal is now prepared by reducing beryllium fluoride with magnesium metal. Beryllium metal did not become readily available to industry until 1957. [Pg.11]

Beryllium Hydride. BeryUium hydride [13597-97-2] is an amorphous, colorless, highly toxic polymeric soHd (H = 18.3%) that is stable to water but hydroly2ed by acid (8). It is insoluble in organic solvents but reacts with tertiary amines at 160°C to form stable adducts, eg, (R3N-BeH2 )2 (9). It is prepared by continuous thermal decomposition of a di-/-butylberylhum-ethyl ether complex in a boiling hydrocarbon (10). [Pg.299]

Reduction of Beryllium Fluoride with Magnesium. The Schwen2feier process (11) is used to prepare a purified, anhydrous beryUium fluoride [7787-49-7], Bep2, for reduction to the metal. BeryUium hydroxide is dissolved in ammonium bifluoride solution to give a concentration of 20 g/L... [Pg.67]

Electrolytic Processes. The electrolytic procedures for both electrowinning and electrorefining beryUium have primarily involved electrolysis of the beryUium chloride [7787-47-5], BeCl2, in a variety of fused-salt baths. The chloride readUy hydrolyzes making the use of dry methods mandatory for its preparation (see Beryllium compounds). For both ecological and economic reasons there is no electrolyticaUy derived beryUium avaUable in the market-place. [Pg.67]

Beryllium Carbide. Beryllium carbide [506-66-17, Be2C, maybe prepared by heating a mixture of beryllium oxide and carbon to 1950—2000°C,... [Pg.75]

Beryllium Carbonates. BeryUium carbonate tetrahydrate [60883-64-9] BeCO 4H2O, has been prepared by passing carbon dioxide through an aqueous suspension of beryUium hydroxide. It is unstable and is obtained only when the solution is under carbon dioxide pressure. BeryUium oxide carbonate [66104-25-4] is precipitated when sodium carbonate is added to a beryUium salt solution. Carbon dioxide is evolved. The precipitate appears to be a mixture of beryUium hydroxide and the normal carbonate, BeCO, and usuaUy contains two to five molecules of Be(OH)2 for each BeCO. ... [Pg.75]

Beryllium fluoride is hygroscopic and highly soluble in water, although its dissolution rate is slow. FluoroberyUates can be readily prepared by crystallization or precipitation from aqueous solution. Compounds containing the BeP ion are the most readily obtained, though compounds containing other fluoroberyUate ions can also be obtained, eg, NH BeF, depending upon conditions. [Pg.75]

BeryUium chloride [7787-47-5], BeCl2, is prepared by heating a mixture of beryUium oxide and carbon in chloride at 600—800°C. At pressures of 2.7—6.7 Pa (0.02—0.05 mm Hg) beryllium chloride sublimes at 350—380°C. It is easily hydrolyzed by water vapor or in aqueous solutions. BeryUium chloride hydrate [14871-75-1] has been obtained by concentrating a saturated aqueous solution of the chloride in a stream of hydrogen chloride. ChloroberyUate compounds have not been isolated from aqueous solutions, but they have been isolated from anhydrous fused salt mixtures. [Pg.75]

Beryllium Nitrate. BeryUium nitrate tetrahydrate [13516-48-0], Be(N02)2 4H2O, is prepared by crystallization from a solution of beryUium hydroxide or beryllium oxide carbonate in a slight excess of dilute nitric acid. After dissolution is complete, the solution is poured into plastic bags and cooled to room temperature. The crystallization is started by seeding. Crystallization from more concentrated acids yields crystals with less water of hydration. On heating above 100°C, beryllium nitrate decomposes with simultaneous loss of water and oxides of nitrogen. Decomposition is complete above 250°C. [Pg.76]

Beryllium Nitride. BeryUium nitride [1304-54-7], Be N2, is prepared by the reaction of metaUic beryUium and ammonia gas at 1100°C. It is a white crystalline material melting at 2200°C with decomposition. The sublimation rate becomes appreciable in a vacuum at 2000°C. Be2N2 is rapidly oxidized by air at 600°C and like the carbide is hydrolyzed by moisture. The oxide forms on beryllium metal in air at elevated temperatures, but in the absence of oxygen, beryllium reacts with nitrogen to form the nitride. When hot pressing mixtures of beryUium nitride and sUicon nitride, Si N, at 1700°C, beryllium sUicon nitride [12265-44-0], BeSiN2, is obtained. BeSiN2 may have appHcation as a ceramic material. [Pg.76]

Beryllium Oxalate. BeryUium oxalate trihydrate [15771 -43-4], BeC204 -3H20, is obtained by evaporating a solution of beryUium hydroxide or oxide carbonate in a slight excess of oxaHc acid. The compound is very soluble in water. Beryllium oxalate is important for the preparation of ultrapure beryllium hydroxide by thermal decomposition above 320°C. The latter is frequentiy used as a standard for spectrographic analysis of beryUium compounds. [Pg.76]

Beryl. 385 Beryllium atomic size, 379 boiling point, 374 bonding capacity, 285 chemistry of, 382 electron configuration. 378 heat of vaporization, 374 ionization energies, 379 occurrence, 384 preparation, 385 properties, 381 structure, 381... [Pg.456]

Procedure. Prepare a solution containing 10 jug of beryllium in 50 mL. (CARE Beryllium compounds are toxic.) Use beryllium sulphate, BeS04,4H20. To... [Pg.175]

Procedure. The beryllium solution (200 mL), prepared with nitric acid or hydrochloric acid and containing about 0.1 g of Be, must be almost neutral and contain no other substance precipitable by ammonia solution. Heat to boiling,... [Pg.449]

Several preparative methods do not use elemental mixtures. Group IIA-Pt intermetallic compounds have been prepared by reacting platinum metal with the group-IIA oxide under hydrogen or ammonia at 900-1200 C. Beryllium metal reacts with neptunium fluoride under vacuum at 1100-1200°C to form BC 3Np. [Pg.471]

Just prior to this time aluminum borohydride (4) and beryllium boro-hydride (5) had been prepared in our laboratories. These are the most... [Pg.4]

The metal beryllium is prepared from its fluoride by magnesiothermic reduction. Calcium can not be used for this purpose because it would interact with beryllium to form a stable intermetallic phase (CaBel3). [Pg.423]

The zinc complex formed with V,V -diphenylformamidinate is structurally analogous to the basic zinc acetate structure, as [Zn4(/i4-0)L6], and the basic beryllium acetate structure. It is prepared by hydrolysis of zinc bis(diphenylformamidinate).184 Mixed metal zinc lithium species were assembled from dimethyl zinc, t-butyl lithium, V.iV -diphenylbenzamidine and molecular oxygen. The amidinate compounds formed are dependent on the solvent and conditions. Zn2Li2 and... [Pg.1160]

Iseler, G. W. et al., Int. Conf. Indium Phosphide Relat. Mater., 1992, 266 Reaction of beryllium, copper, manganese, thorium or zirconium is incandescent when heated with phosphorus [1] and that of cerium, lanthanum, neodymium and praseodymium is violent above 400°C [2], Osmium incandesces in phosphorus vapour, and platinum bums vividly below red-heat [3], Red phosphorus shows very variable vapour pressure between batches (not surprising, it is an indeterminate material). This leads to explosions when preparing indium phosphide by reactions involving fusion with phosphorus in a sealed tube [4],... [Pg.1887]


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See also in sourсe #XX -- [ Pg.876 ]

See also in sourсe #XX -- [ Pg.54 ]




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