Beryllium Hydroxides

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. 

Beryllium Oxide. Beryllium oxide [1304-56-9], BeO, is the most important high purity commercial beryllium chemical. In the primary industrial process, beryllium hydroxide extracted from ore is dissolved in sulfuric acid. The solution is filtered to remove insoluble oxide and sulfate impurities. The resulting clear filtrate is concentrated by evaporation and upon cooling high purity beryllium sulfate, BeSO 4H20, crystallizes. This salt is... 

Ceramic-grade beryllium oxide has also been manufactured by a process wherein organic chelating agents (qv) were added to the filtered beryllium sulfate solution. Beryllium hydroxide is then precipitated using ammonium hydroxide, filtered, and carefully calcined to obtain a high purity beryllium oxide powder. 

Moving down in a column is equivalent in many respects to moving to the left in the periodic table. Since we find basic properties predominant at the left of the periodic table in a row, we can expect to find basic properties increasing toward the bottom of a column. Thus the base strength of the alkaline earth hydroxides is expected to be largest for barium and strontium. The greatest acid strength is expected for beryllium hydroxide. 

Only beryllium hydroxide dissolves appreciably in strong base solutions,... 

The precipitation by ammonia solution of such elements as Al, Bi, Cd, Cr, Ca, Cu, Fe, Pb, Mn, Ni, and Zn may be prevented by complexation with EDTA upon boiling the ammoniacal solution, beryllium hydroxide is precipitated quantitatively. 

Three different forms of beryllium hydroxide in the solid state have been described (10, 52, 53, 100). The amorphous form of Be(OH)2 is obtained as a gelatinous precipitate when alkali is added to a beryllium-containing solution at ambient temperatures. The gelatinous precipitate is slowly transformed into the metastable a form when the mixture is allowed to stand. The stable fi form is obtained after the mixture has aged for some months or by precipitation at 70°C. The value of log K for the equilibrium between a and (3 forms,... 

Copaux-Kawecki An improved version of the Copaux process for extracting beryllium from beryl, which permits recovery of the fluorine. Addition of ferric sulfate to the dilute sodium fluoride solution remaining after the separation of the beryllium hydroxide precipitates sodium tetrafluoroferrate, which is then used in place of sodium fluorosilicate. 

Schwenzfeier-Pomelee A process for purifying beryllium and producing glassy beryllium fluoride. Beryllium hydroxide is dissolved in aqueous ammonium hydrogen fluoride various metal impurities are removed by successive precipitations, and ammonium fluoroberyllate is crystallized under vacuum. When this is heated, ammonium fluoride vaporizes and molten beryllium fluoride remains. 

This behaviour distinguishes beryllium hydroxide from the other hydroxides of Group II which are not amphoteric this amphoterism is also shown by aluminium hydroxide in Group III, and it has been discussed more fully in Chapter 2, where we saw it as characteristic of small ions of high charge, i.e. Be2+ and Al3+. 

Preparation. The ores are converted to an acid-soluble form by fusion chemical processes to obtain beryllium hydroxide or oxide and then beryllium chloride or fluoride are then applied, followed by electrolysis in the melt. 

Synonyms/compounds Glucinium beryllium oxide beryllium chloride beryllium fluoride beryllium hydroxide beryllium phosphate beryllium nitrate beryllium sulfate beryllium carbonate... 

Beryllium metal, beryllium-aluminum alloy, beryl ore, beryllium chloride, beryllium fluoride, beryllium hydroxide, beryllium sulfate, and beryllium oxide all produce lung tumors in rats exposed by inhalation or intra-tracheally. The oxide and the sulfate produce lung tumors in monkeys after intrabronchial implantation or inhalation. A number of compounds produce osteosarcomas in rabbits after their intravenous or intramedullary administration. ... 

Metallic beryllium is produced by reduction of beryllium halide with sodium, potassium or magnesium. Commercially, it is obtained primarily from its ore, beryl. Beryllium oxide is separated from silica and alumina in ore by melting the ore, quenching the solid solution, and solubilizing in sulfuric acid at high temperatures and pressure. Silica and alumina are removed by pH adjustment. Beryllium is converted to its hydroxide. Alternatively, beryl is roasted with complex fluoride. The products are dissolved in water and then pH is adjusted to produce beryllium hydroxide. 

Reactions with alkalies first produce insoluble beryllium hydroxide with evolution of hydrogen. Excess alkali converts the hydroxide to water-soluble beryllate ... 

Beryllium hydroxide is used to produce beryllium oxide and other beryllium compounds. 

Beryllium hydroxide is prepared by treating basic beryllium acetate, Be40(C2H302)e with caustic soda solution or by precipitation from a strongly alkaline solution of sodium beryllate. The precipitate is dried at 100°C. 

Arfwedson fused the chrysoberyl three times with caustic potash in a silver crucible. Since a portion of the melt corresponding to about 18 per cent of the mineral failed to dissolve in hydrochloric acid, he reported this residue as silica. It is now known that beryllium hydroxide, when freshly precipitated, dissolves readily in hydrochloric acid, but becomes after a time almost completely insoluble in it (17). Therefore, it is probable that Arfwedson s silica was really the beryllium hydroxide. He then precipitated the alumina by adding ammonium hydroxide to the acid filtrate. To satisfy himself of the purity of his alumina, he saturated the alkaline solution with hydrochloric acid until the precipitate dissolved, and added a large excess of ammonium carbonate. Had any glucina [beryllia] or yttria existed in the matter, said Arfwedson, it would have been dissolved by this excess of carbonate of ammonia, and would have fallen when the filtered liquid was boiled till the excess of ammonia was driven off but the liquid stood this test without any precipitate appearing. Arfwedson was evidently unable to detect beryllia here because he had already filtered it off and reported it as silica. When American chemist Henry Seybert analyzed the same mineral in 1824 he found it to contain 15 to 16 per cent of beryllia (22). 

Beryllium hydroxide see Beryllium and beryllium compounds) Beryllium-nickel alloy see Beryllium and beryllium compounds) Beryllium oxide see Beryllium and beryllium compounds)... 

Preparation and Properties of Beryllium Hydroxide. Add a 10% ammonia solution dropwise to 4-5 ml of a 3% beryllium sulphate solution up to the complete formation of a precipitate. See how beryllium hydroxide reacts with 10% solutions of sodium hydroxide (use a minimum amount of the alkali) and acids. Boil the alkaline... 

How can you explain the fact that when an aqueous solution of an alkali metal beryllate is heated beryllium hydroxide precipitates, while when an aqueous solution of beryllium chloride or sulphate is heated no beryllium hydroxide precipitate forms ... 

Dissolve about 10 g. of commercial beryllium hydroxide or carbonate in acetic acid and evaporate to dryness on the hot plate. Dissolve the dry residue in boiling glacial acetic acid and set aside for crystallization. The salt is deposited in small colorless octahedra. These should be drained on a Witte plate and dried on paper. The salt is decomposed by wat er. 

Beryllium reacts readily with sulfuric, hydrochloric, and hydrofluoric acids. Dilute nitric acid attacks the metal slowly, whereas concentrated nitric acid has litde effect. Hot concentrated alkalies give hydrogen and the amphoteric beryllium hydroxide [13327-32-7], Be(OH)2. Unlike the aluminates, the beryllates are hydrolyzed at the boil. 

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