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| | SILICA Chemical Properties |
| Melting point | 1610 °C(lit.) | | Boiling point | >100 °C(lit.) | | density | 2.6 g/mL at 25 °C(lit.) | | refractive index | n20/D 1.544(lit.) | | storage temp. | 2-8°C | | form | tablets (~0.5 g each) | | InChIKey | VYPSYNLAJGMNEJ-UHFFFAOYSA-N | | EPA Substance Registry System | Cristobalite (14464-46-1) |
| Hazard Codes | Xn,T | | Risk Statements | 48/20 | | Safety Statements | 22 | | WGK Germany | 3 | | RTECS | VV7340000 | | F | 3 | | HS Code | 28112290 | | Toxicity | TCLo inhalation in human: 16mppcf/8H/17 |
| | SILICA Usage And Synthesis |
| Chemical Properties | Silicon dioxide/crystalline silica is a component of many mineral dusts and materials which melts to a glass at very high temperature. | | Uses | Because of its unique physical and chemical properties, crystalline silica has many uses. Commercially produced silica products include quartzite, tripoli, ganister, chert, and novaculite. Crystalline silica also occurs in nature as agate, amethyst, chalcedony, cristobalite, flint, quartz, tridymite, and, in its most common form, sand (IARC 1997). Naturally occurring silica materials are classified by end use or industry. Sand and gravel are produced almost exclusively for road building and concrete construction, depending on particle size and shape, surface texture, and porosity (IARC 1987).
| | Definition | A hygroscopic substance such as activated alumina, calcium chloride, silica gel, or zinc chloride. Such substances adsorb water vapor from the air and are used to maintain a dry atmosphere in containers for food packaging, chemical reagents, etc. | | Definition | Cristobalite: a mineral form of silicon(IV) oxide, SiO2. | | Safety Profile | Confirmed carcinogen with experimental carcinogenic and tumorigenic data. Poison by intratracheal route. An inhalation hazard. Human systemic effects by inhalation: cough, dyspnea, fibrosis. About twice as toxic as silica in causing sihcosis. See also other sdica entries | | Potential Exposure | 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. | | Carcinogenicity | Respirable crystalline silica, primarily quartz dusts occurring in industrial and occupational settings, is known to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in humans. Respirable crystalline silica was first listed in the Sixth Annual Report on Carcinogens in 1991 as reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals; the listing was revised to known to be a human carcinogen in the Ninth Report on Carcinogens in 2000. | | Incompatibilities | Violent reactions with powerful oxidizers: fluorine, chlorine trifluoride; manganese trioxide; oxygen difluoride, hydrogen peroxide, etc.; acetylene; ammonia. | | Waste Disposal | Sanitary landfill |
| | SILICA Preparation Products And Raw materials |
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