オキシビスカリウム 化学特性,用途語,生産方法
解説
酸化カリウム.金属カリウムを真空中で加熱し,少量の乾燥空気と反応させて得られる.室温で白色の粉末,熱すれば黄色となる.密度2.32 g cm-3.350 ℃ で分解してK2O2とKとになる.潮解性で,水に溶かすとはげしく反応して水酸化カリウムを生じる.エタノール,エーテルに可溶.断熱保温材成分,ガラス繊維,うわぐすり成分として用いられる.金属カリウムの液体アンモニア溶液に-50 ℃ で徐々に酸素を通じるか,または水酸化カリウムと過酸化水素の混合水溶液を真空中で濃硫酸上で蒸発させると二水和物が得られる.橙色の粉末.加熱によりK2Oと O2 に分解する.吸湿性があり,水と反応してKOHと O2 に分解する.
化学的特性
gray crystal(s) mass; hygroscopic [CRC10] [HAW93]
使用
Potassium oxide is a strong alkaline flux which is similar to sodium oxide but is slightly less strong and it begins its fluxing action earlier than does sodium oxide, at approximately 1382°F (750°C). It's a predictable, stable flux that produces bright glossy glazes, but it can't be used alone as a flux. Potassium produces slightly stronger glaze surfaces than does sodium oxide. Its low viscosity and surface tension create fluid glaze melts, but its high coefficient of expansion and contraction may cause crazing.
As mentioned above, potassium oxide is often found combined with sodium oxide, so it's often written as KNaO. lt's only slightly volatile at ceramic temperatures and is just slightly soluble.Usually used in its insoluble forms as feldspars or slightly soluble frits, potassium oxide can also be introduced to the glaze recipe as soluble pearl ash (potassium carbonate), which can cause some flashing like sodium carbonate.
Insoluble sources of potassium oxide are potash feldspars such as Custer, G-200, K-200, A-3, Kona F-4(Del Monte), Cornwall stone, Plastic Vitrox, volcanic ash, Kona A-1, Bell, Eureka, A-300, and mica. All soda feldspars have some potassium oxide; frits P-25, 3110, and 3124 contain minor amounts. Soluble forms of potassium oxide include pearl ash(K2CO3), potassium nitrate (saltpeter), and unwashed wood ash.
定義
ChEBI: A metal oxide with formula K2O.
一般的な説明
A white-colored crystalline solid. Denser than water. Contact may severely irritate skin, eyes and mucous membranes. May be toxic by ingestion, inhalation and skin absorption. Used to make other chemicals.
空気と水の反応
Soluble in water. The oxides of potassium react with water vigorously and with enough evolution of heat to cause boiling and spattering of hot caustic solution, [Chemical Safety Data Sheets SD-9, SD-10. 1947]. Reacts with warm water with violent explosion [Thorpe and Tlitton J. Chem. Soc. 59:1019: 1891].
反応プロフィール
The higher oxides of potassium, formed in air, react explosively with pure potassium, sodium, sodium-potassium alloys, and organic matter [Mellor 2, Supp. 3:1559. 1963].
健康ハザード
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
火災危険
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
参考文献
E. Zintl, A. Harder, B. Dauth, Z. Electrochem., 40, 588 (1934).
オキシビスカリウム 上流と下流の製品情報
原材料
準備製品