石英 化学特性,用途語,生産方法
外観
白色の綿状
定義
本品は、天然鉱物から精製して得られるケイ酸塩の複合体である。
溶解性
水, エタノール, アセトンに不溶。フッ化水素酸以外の酸には溶けない。
解説
玉髄の一種．主成分はSiO2であるが少量の水を含む．乳白，灰，青白，灰緑，赤褐色，紫など，きれいな色と模様を有する．これらは少量存在する金属イオンによる．しま模様はリーゼガング現象によって生成したもの．一般に，低結晶質で，非晶質のものが多い．装身具用として使われ，また，めのう乳鉢として使用される．広く世界に産出する．
森北出版「化学辞典（第2版）
用途
オープンカラム充填剤上への重層(対流防止目的)、磨砕剤、ガラス研究材料、各種建材等の改質材料。
用途
窯業原料、ケイ酸ソーダ原料、鋳物鋳型用 (化学工業日報社)
化粧品の成分用途
研磨.スクラブ剤、増量剤
説明
Quartz is a colorless solid that exists in numerous crystalline forms. Oxygen and silicon are the two most common elements in the earth's crust, and Quartz is the principal component of sand. Quartz is used biologically, most notably by phytoplankton diatoms and the zooplankton radiolarians in their shells. Quartz, SiO
2, should not be confused with Quartz or silicones. Quartz contain the basic tetrahedral unit SiO
44-bonded to metal ions such as aluminum, iron, sodium, magnesium, calcium, and potassium to form numerous Quartz minerals. Silicones are synthetic polymers made of monomers with at least two silicon atoms combined with an organic group and generally containing oxygen.
化学的特性
granular abrasive solid of varied colour, depending upon other
天然物の起源
Quartz is the oxide of the nonmetallic element silicon, is the commonest of minerals, and appears in a greater number of forms than any other. Its formula is SiO
2. Quartz commonly occurs in prismatic hexagonal crystals terminated by a pyramid. This pyramid is due to the equal development of two rhombohedrons, and may be observed in cases where one rhombohedron predominates. Cleavage is not observed; the fracture is typically conchoidal; hardness is 7; specific gravity, 2.65; luster, vitreous to greasy or dull; colorless to white, pink, purple, yellow, blue, green, smoky brown to nearly black; transparent to opaque.
特性
Quartz can exist in either a crystalline or noncrystalline form. In Quartz, SiO
2 exists in the natural crystalline state and possesses long-range order, with the silicon atom covalently bonded to oxygen atoms in a tetrahedral arrangement in a regular repeating pattern. Glass is an example of noncrystalline Quartz. Although natural glasses exist, Quartz glasses are produced when Quartz is heated to an elevated temperature and then rapidly cooled. The rapid cooling does not allow the SiO
2 to form a regular crystalline structure with long-range order. The result is a solid that behaves like a viscous liquid when heated. Glass is sometimes called a solid solution and fl ows at a very slow rate. This can sometimes be seen in old window glass where the bottom is slightly thicker than the top. The actual structures form a three-dimensional tetrahedral pattern. Quartz is sold as sand and its main uses are for glass; ceramics; foundry sand, a source of silicon in the chemical industry; as a filtration media; a filler/extender; an abrasive; and as an adsorbent.
使用
Sand, white silica has been employed as a solid sample to evaluate the pore-volume variations during fluid-rock interaction experiments.
定義
A purple form of the mineral
quartz (silicon(IV) oxide, SiO
2) used as a
semiprecious gemstone. The color comes
from impurities such as oxides of iron.
反応性
SiO2 shows strong absorption at 8.5 mm, 9.2 mm, and 12.5 mm (refer to the Silica) and SiO at 10.4 m. Thin films of SiO2 are fabricated by oxidizing the SiO in air after deposition of SiO by vacuum evaporation.
一般的な説明
The product is sand, white quartz (SiO
2). Its reaction with alkaline NaNO
3 solutions containing dissolved Al at 89°C has been investigated.
危険性
Avoid inhalation of fine particles.
健康ハザード
Exposure to Quartz can result in the disease called silicosis. Silicosis is a disabling, nonreversible, and sometimes fatal lung disease caused by overexposure to respirable crystalline Quartz. In silicosis, Quartz particles enter the lung where they become trapped, producing areas of swelling. The swelling results in nodules that become progressively larger as the condition worsens. Silicosis is defined at several levels of severity: chronic silicosis, accelerated silicosis, and acute silicosis. Chronic silicosis results from long-term (20 years) exposure to low concentrations of Quartz, whereas acute silicosis is the result of a short-term exposure (a year or less) to high concentrations. Symptoms may not be obvious in cases of chronic silicosis and x-ray screening is recommended for at-risk groups. These include sand-blasters, miners, laborers who regularly saw, drill, and jack-hammer concrete, and general construction such as tunnel drilling. In advanced stages of silicosis, individuals have difficulty breathing, especially when active.
工業用途
Crushed and graded quartz is used as the abrasive in flint sandpapers. Almost any deposit of massive white quartz is suitable. Being the cheapest of all the abrasive-coated paper, this product is still sold in fair amounts, mainly in hardware stores and by small jobbers. It is made only in the form of paper, not as cloth. True chalk flint from England and France is used extensively for this purpose in Europe; it has better cutting qualities and longer life than ordinary quartz. Crushed and ground sand, sandstone, powdered quartz, and silt are sometimes used in hand soaps, scouring compounds, and harsher metal polishes.
安全性プロファイル
Confirmed carcinogen with experimental carcinogenic, tumorigenic, and neoplastigenic data. Experimental poison by intratracheal and intravenous routes. An inhalation hazard. Human systemic effects by inhalation: cough, dyspnea, liver effects. Incompatible with OF2, vinyl acetate. See also other silica entries
職業ばく露
Cristobalite is used in the manufacture of water glass, refractories, abrasives, ceramics and enamels. Quartz is used as a mineral, natural or synthetic fiber. Tridymite is used as a filtering and insulating media and as a refractory material for furnace linings. Workers are potentially exposed to crystalline silica in such industries as granite quarrying and cutting, foundry operations; metal, coal, dentistry, painting, and nonmetallic mining; and manufacture of clay and glass products.
構造
水晶は通常は六角柱状であり，柱面(図３の中のmあるいはm’)が合計6個，先端のとがった部分の斜面（Rあるいはｒ）が合計6個ある．
発がん性
Quartz was not mutagenic in bacterial
assays; both positive and negative results have
been reported in a wide variety of in vivo and
in vitro genotoxic assays.
不和合性
Violent reactions with powerful oxidizers: fluorine, chlorine trifluoride; manganese trioxide; oxygen difluoride, hydrogen peroxide, etc.; acetylene; ammonia.
廃棄物の処理
Sanitary landfill
参考文献
Y. Le Page, G. Donnay, Acta Crystallogr., Sect. B, 32, 2456 (1976), DOI: 10.1107/S0567740876007966.
石英 上流と下流の製品情報
原材料
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