| Identification | More | [Name]
Calcium fluoride | [CAS]
7789-75-5 | [Synonyms]
Calcium difluoride
CALCIUM FLUORIDE
CALCIUM (II) FLUORIDE
FLUORITE
FLUORSPAR
FLUORSPARMEAL
NATURAL FLUOROSPAR
Acid-spar
CaF2
Calcium fluoride (CaF2)
calciumfluoride(caf2)
calciumfluoride[caf2]
Fluorite, fluorspar
Irtran 3
irtran3
Liparite
Met-spar
naturalfluorite
calcium fluoride anhydrous
Calcium fluoride 98% | [EINECS(EC#)]
232-188-7 | [Molecular Formula]
CaF2 | [MDL Number]
MFCD00010907 | [Molecular Weight]
78.07 | [MOL File]
7789-75-5.mol |
| Chemical Properties | Back Directory | [Definition]
A pure naturally occurring form of calcium fluoride. | [Appearance]
Calcium fluoride is colorless crystalline
or white, powdery substance. | [Melting point ]
1402 °C
| [Boiling point ]
2500 °C (lit.) | [density ]
3.18 g/mL at 25 °C(lit.)
| [refractive index ]
1.434 | [Fp ]
2500°C | [storage temp. ]
-20°C | [solubility ]
Slightly soluble in acid; insoluble in acetone. | [form ]
rod
| [color ]
white
| [Specific Gravity]
3.18 | [Stability:]
Stable. Incompatible with acids. | [Water Solubility ]
INSOLUBLE | [Sensitive ]
Hygroscopic | [Merck ]
14,1667 | [Solubility Product Constant (Ksp)]
pKsp: 8.28 | [Dielectric constant]
2.5（Ambient） | [Exposure limits]
ACGIH: TWA 2.5 mg/m3
NIOSH: IDLH 250 mg/m3; TWA 2.5 mg/m3 | [InChIKey]
WUKWITHWXAAZEY-UHFFFAOYSA-L | [CAS DataBase Reference]
7789-75-5(CAS DataBase Reference) | [NIST Chemistry Reference]
Calcium fluoride(7789-75-5) | [EPA Substance Registry System]
7789-75-5(EPA Substance) |
| Safety Data | Back Directory | [Hazard Codes ]
Xi,Xn | [Risk Statements ]
R36/37/38:Irritating to eyes, respiratory system and skin . | [Safety Statements ]
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S37/39:Wear suitable gloves and eye/face protection .
S36:Wear suitable protective clothing . | [RIDADR ]
3288 | [WGK Germany ]
1
| [RTECS ]
EW1760000
| [Hazard Note ]
Irritant | [TSCA ]
Yes | [HS Code ]
28261900 | [Safety Profile]
Moderately toxic by
intraperitoneal route. Mildly toxic by
ingestion. An experimental teratogen. Other
experimental reproductive effects. Mutation
data reported. See also FLUORIDES and
CALCIUM COMPOUNDS. When heated
to decomposition it emits toxic fumes of F-. | [Hazardous Substances Data]
7789-75-5(Hazardous Substances Data) | [Toxicity]
LD50 i.p. in mice: 2638.27 mg/kg (Stratmann) |
| Hazard Information | Back Directory | [General Description]
Odorless gray powder or granules. Sinks in water. | [Reactivity Profile]
CALCIUM FLUORIDE has weak oxidizing or reducing powers. Redox reactions can however still occur. The majority of compounds in this class are slightly soluble or insoluble in water. If soluble in water, then the solutions are usually neither strongly acidic nor strongly basic. These compounds are not water-reactive. | [Hazard]
An irritant. | [Health Hazard]
Little acute toxicity | [Potential Exposure]
Calcium fluoride is used for production of hydrofluoric acid; as a flux in steel manufacture; in
smelting; electric arc welding, making glass and ceramics;
and to fluoridate drinking water. | [First aid]
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical attention. A doctor or authorized paramedic may consider administering aluminum hydroxide gel, if conscious | [Shipping]
Calcium fluoride is not specifically covered by
DOT in its Performance-Oriented Packaging Standards. | [Incompatibilities]
Dust may form explosive mixture with
air. Reacts with water, moist air, and steam, releasing flammable hydrogen gas; and may self-ignite in air. A strong
reducing agent; incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Incompatible with metal
halogenates, silver fluoride, and tetrahydrofuran | [Description]
Calcium fluoride is colorless crystalline orwhite, powdery substance. Molecular weight=78.08;Specific gravity (H2O:1)=3.18 at 20℃; Boilingpoint=2495℃; Freezing/Melting point=1423℃. HazardIdentification (based on NFPA-704 M Rating System):Health 2, Flammability 0, Reactivity 0. Practically insolublein water. | [Physical properties]
White cubic crystal or powder; refractive index 1.434; density 3.18 g/cm3; hardness 4 Mohs; melts at 1,418°C; vaporizes at 2,533°C; insoluble in water (16 mg/L at 20°C); Ksp 3.9x10-11; slightly soluble in dilute mineral acid; soluble in concentrated acids (with reaction). | [Production Methods]
The commercial product is obtained from naturally occurring mineral fluorspar, which is purified and powdered. Also, it may be precipitated by mixing a solution of sodium fluoride with a soluble calcium salt:
Ca(NO3)2 + 2NaF → CaF2 + NaNO3
Alternatively, it may be obtained by treating calcium carbonate with hydrofluoric acid：CaCO3 + 2HF → CaF2 + CO2 + H2O. | [Flammability and Explosibility]
Nonflammable | [Industrial uses]
Also called fluorite, fluorspar is a crystalline or massive granular mineral of the composition CaF2, used as a flux in the making of steel, for making hydrofluoric acid, in opalescent glass, in ceramic enamels, for snaking artificial cryolite, as a binder for vitreous abrasive wheels,and in the production of white cement. It is a better flux for steel than limestone, making a fluid slag, and freeing the iron of sulfur and phosphorus.
Acid spar is a grade used in making hydrofluoric acid. It is also used for making refrigerants, plastics, and chemicals, and for aluminum reduction. Optical fluorspar is the highest grade but is not common. Fluoride crystals for optical lenses are grown artificially from acid-grade fluorspar. Pure calcium fluoride, Ca2F6, is a colorless crystalline powder used for etching glass, in enamels, and for reducing friction in machine bearings. It is also used for ceramic parts resistant to hydrofluoric acid and most other acids. Calcium fluorite has silicon in the molecule and is a crystalline powder used for enamels. The clear rhombic fluoride crystals used for transforming electric energy into light are lead fluoride, PbF2. | [storage]
Color Code—Green: General storage may be used.Store in tightly closed containers in a cool, well-ventilatedarea away from acids and chemically active metals (such aspotassium, sodium, magnesium, and zinc) because corrosivehydrogen fluoride will be produced. |
| Questions And Answer | Back Directory | [Chemical Properties]
Calcium fluoride is the main ingredient of fluorspar or fluorite, the chemical formula is CaF2, it is colorless cubic crystal or white powder. The relative density is 3.18, the melting point is 1423℃, boiling point is about 2500 ℃. The solubility in water is minimal , 100g water can dissolve only 0.0016g at 18 ℃, it is insoluble in acetone, but soluble in hydrochloric acid, hydrofluoric acid, sulfuric acid, nitric acid and ammonium salt solution, and it can not react with dilute acid, but can react with hot concentrated sulfuric acid and generate hydrofluoric acid, it can form a complex when dissolves in aluminum and iron salts (Fe3 +) solution.
Natural calcium fluoride is mineral fluorite or fluorspar, often shows gray, yellow, green, purple and other colors, sometimes it is colorless, transparent, shiny glass, brittle, and the relative density is 3.01~3.25, it has significant phenomenon of fluorescence. It can be used as the source of fluorine and the material to make hydrofluoric acid system, fluoride; and it can also be used in terms of the manufacture of glass, enamel, glaze. Fluorite is mainly used as a flux in metallurgy, the very pure fluorspar can be used to make specialty lenses. Water when contains (1~1.5) × 10-6 calcium fluoride can prevent dental problems. In addition, it can be used in smelting iron and steel, chemicals, glass, ceramics manufacturing. Pure product can be used for catalyst of dehydration, dehydrogenation. By the effect of soluble calcium salts (calcium carbonate or calcium hydroxide) and sodium fluoride or hydrofluoric acid, ammonium fluoride, calcium fluoride can be obtained.
| [crystal structure]
Calcium fluoride is an ionic crystal with the fluorine anions in a simple cubic array and calcium cations in half of the cubic sites of the structure. The calcium ions can also be thought of as being on an "expanded" fcc lattice with the fluorine ions causing their lattice separation to be 0.39 nm. This representation is shown in the lower diagram. The unit cell has 4 Ca2+ ions and 8 F1- ions.
The material is transparent in the visible spectral region, and shows electronic optical adsorption in the ultra violet and lattice optical absorption in the infrared. | [Uses]
Industry
Application
Role/benefit
Chemical manufacture
Production of hydrofluoric acid and fluoride
Raw material/source of fluoride
Production of fluorine fine chemicals and synthetic cryolite
Raw material/source of fluoride
Architectural material
Production of glass
Fluxing agent/promote the melting of raw materials
Production of cement
Mineralization agent
Production of ceramic glaze
Fluxes and coloring aids
Metallurgy
Iron and steel smelting, ferroalloy production,etc.
Fluxing agent/reduce the melting point of refractory substances
Medicine
Treatment, control, prevention, & improvement of allergic reactions
Promoting new bone formation
Thermal imaging systems, spectroscopy, telescopes and excimer lasers
Manufacture of optical components, such as windows and lenses
Raw material/broad range of transmission light frequencies; low refractive index; high thermo stability
Others
Production of welding agents
Important components in coatings of welding rods and welding powders
Dehydration and dehydrogenation reaction
Catalyst/accelerate the process of reaction
Manufacture of brake lining
Additive/helps reduce abrasion caused by high heat and friction
| [Production method]
The fluorite deposits which have been found in china, are main used the mine using underground mining method, or shallow open-pit mining, and underground deep mining, for ore body most tilt vein, the extending is also large.
Mining method is based in shallow hole Shrinkage Method based. Mining process sees "phosphate rock." Beneficiation methods have two types generally, the one is raw ore can become qualified ore concentrate by handling select, the second is hand-selected lean ore and tailings.
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