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CAS NUMBER: 16961-83-4

EC NUMBER: 241-034-8





Fluosilic acid is an inorganic compound with the chemical formula H2SiF6. 
Aqueous solutions of Fluosilic acid consist of salts of the cation and hexafluorosilicate anion. 
These salts and their aqueous solutions are colorless.
Fluosilic acid is produced naturally on a large scale in volcanoes.
Fluosilic acid is manufactured as a coproduct in the production of phosphate fertilizers. 

The resulting Fluosilic acid is almost exclusively consumed as a precursor to aluminum trifluoride and synthetic cryolite, which are used in aluminium processing. 
Fluosilic acid appears as a colorless fuming liquid with a penetrating pungent odor. 
Fluosilic acid is corrosive to metals and tissue. 
Both the fumes and very short contact with the liquid can cause severe and painful burns. 

Fluosilic acid is used in water fluoridation, in hardening cement and ceramics, as a wood preservative.
The major use of sodium hexafluorosilicate and fluosilic acid is as fluoridation agents for drinking water. 
Both chemicals are also used as a chemical intermediate (raw material) for aluminum trifluoride, cryolite (Na3AlF6), silicon tetrafluoride, and other fluorosilicates and have found applications in commercial laundry. fluosilic acid is used in the tanning of animal hides and skins, in ceramics and glass, in technical paints, in oil well acidizing, in the manufacture of hydrogen fluoride, for the sterilization of equipment (e.g., in brewing and bottling establishments and for copper and brass vehicles), and in electroplating. It is also employed as an impregnating ingredient to preserve wood and harden masonry and for the removal of mold as well as rust and stain in textiles.
Fluosilic acid is mainly produced as a byproduct of the manufacture of phosphate fertilizers.

Fluosilic acid is colorless and strongly acidic. 
Fluosilic acid's corrosive. 
Fluosilic acid eats through glass. 
Store in wax or plastic containers. 

Colorless dihydrate crystals were precipitated when the concentrated solution was cooled, and the melting point was 19ºC. 
Fluosilic acid has disinfecting properties
Fluosilic acid is an organic colourless fuming liquid with a penetrating pungent odour. 
Fluosilic acid is produced as a by-product of hydrogen fluoride and phosphoric acid production. 

Fluosilic acid is usually disposed by converting it into inert harmless waste products by neutralization it with limestone or milk of lime.
Fluosilic acid ((H3O)2SiF6 or H2SiF6 in aqueous solution) is produced as a by-product from the production of hydrogen fluoride (HF) in a process where where fluospar is treated with sulfuric acid. 
Fluosilic acid is also produced as a by-product in plants processing phosphate rock to produce of phosphoric acid from apatite and fluorapatite (USGS 2015).
Fluosilic acid acid is mainly converted to aluminium fluoride and cryolite which are central to the conversion of aluminium ore into aluminium metal. 
Fluosilic acid is also used in water fluoridation and its salts are used for several purposes.
Fluosilic acid is usually used in toothpastes, and also for the fluoridation of water for maintaining fluoride levels in water by municipal corporations. 

Tooth decay can be prevented by maintaining fluoride levels. 
Fluosilic acid is liquid in nature, hence it is easy to handle and occupational hazards of handling fine power can be prevented. 
Fluosilic acid’s increasing demand in fluoridation of drinking water is expected to be the major market driver. 
Increasing demand from the textile industry is also expected to boost the fluosilic acid market, as Fluosilic acid is used in removing rust and stains from the fabrics. 
However, fuming the property and corrosive nature of fluosilic acid may hamper its demand. 

Fluosilic acid is a by-product of the phosphate fertilizer industry, therefore it may be contaminated with radioactive elements and heavy metals which may act as a market restraint.
Fluosilic acid is used in different applications such as electroplating, oil well acidizing, sterilization, commercial laundry, wood preservative, neutralizing agent, stain and rust removing, and for tanning of ceramic and glass.
Fluosilic acid is used in manufacturing commercial detergents such as silicon tetrafluoride, cryolite, and other fluorosilicicates.
Fluosilic acid is used in mixing, preparation or repackaging, as an interim product in the synthesis of chemicals, as a process auxiliary means for cleaning and disinfection. 

Fluosilic acid is also applied in water fluorination, the treatment of the surfaces of metals, production of basic metals, acid decomposition of minerals, professional cleaning and disinfection as well as a laboratory chemical.
Fluosilic acid can be also a source of active silica which is a valuable product that can be used in the phosphoric acid industry itself to neutralize the highly corrosive Hydrofluoric Acid (HF), it can be also used in many other industries.
Fluosilic acid is a colorless liquid that is soluble in water. 
Fluosilic acid is highly corrosive and toxic,attacking glass and stoneware. 
Fluosilic acid is used in water fluoridation, electroplating, and in manufacturing enamels and cement. 

Fluosilic acid is a transparent, colorless fuming liquid.Hexafluosilic acid is a kind of inorganic acid. 
Fluosilic acid is majorly used for the fluoridation of water
Fluosilic acid is a clear, colorless liquid that is used in a variety of industrial applications.
Due to its ease of use over competing technologies, Fluosilic acid is commonly used in water fluoridation applications. 
Fluosilic acid is also used for hardening masonry and ceramics, as a metal surface treatment and cleaner, pH adjustment in industrial textile processing or laundries, and as an intermediate in the manufacturing of chemicals.

Fluosilic acid is incompatible with metals, glass, alkali, ceramics, and strong concentrated acids. 
Strong concentrated acids will cause the release of poisonous hydrogen fluoride. 
Fluosilic acid will attack glass and ceramics and metals will corrode and liberate hydrogen gas. 



-In the plastic industry, Fluosilic acid is mainly used as a reducing agent , nylon whitening agent , plasticizer , synthetic fiber , etc.
-Fluosilic acid is also used in the production of herbicides , fungicides and water stabilizers in the organophosphorus pesticide industry.
-Fluosilic acid is also used to produce ATMP , a high-performance water treatment agent.
-Printing and dyeing auxiliary
-Mainly used in natural silk fabric fields.
-Dyeing auxiliaries, mainly used for natural silk fabrics, tablecloths for printing dialing agent



-High profitability
-Zero cost raw materials
-Minimum hold-up AHF in the plant
-High quality anhydrous hydrofluoric acid
-Reliability in operation



Hexafluosilic acid has been crystallized as various hydrates. 
These include (H5O2)2SiF6, the more complicated (H5O2)2SiF6·2H2O, and (H5O2)(H7O3)SiF6·4.5H2O. 
In all of these salts, the octahedral hexafluorosilicate anion is hydrogen bonded to the cations.
Aqueous solutions of hexafluosilic acid are often described as H2SiF6.



-Hardener and water repellent to improve the hardness and strength of concrete
-Fluorine weathering treatment on the surface of silica building
-Ceramic manufacturing
-Control insect on fabric insecticide.



Fluosilic acid is produced commercially from fluoride-containing minerals that also contain silicates. 
Specifically, apatite and fluorapatite are treated with sulfuric acid to give phosphoric acid, a precursor to several water-soluble fertilizers. 
This is called the wet phosphoric acid process.
Some of the Fluosilic acid produced during this process in turn reacts with silicon dioxide (SiO2) impurities, which are unavoidable constituents of the mineral feedstock, to give silicon tetrafluoride.



Fluosilic acid is used as a chemical intermediate, a disinfectant, a water fluoridating agent, a wood preservative, a masonry and ceramic hardener, and a glass additive.
Fluosilic acid is also used to treat hides and skins, to electroplate chromium, and to electrolytically refine lead.
Fluosilic acid is used in technical paints, oil well acidizing, and to remove mold, rust, and stains from textiles.

-pH adjuster and fluoridation agent for drinking water
-sterilizing agent in brewingbottling industries, glass bottles; wood preservativeimpregnant
-hardening ceramics and cements
-disinfecting copper and brass vessels
-electroplating bath ingredient
-manufacturing of aluminum fluoride, synthetic cryolite, hydrogen fluoride
-curing agent for bricks, tiles; lead refining electrolyte
-mineral flotation agent (phosphate ores)
-tanning auxiliaries
-bonding agent for aluminum foil, stabilizer or preservative in food packaging adhesives



-Curing Agent



In water, hexafluosilic acid readily hydrolyzes to hydrofluoric acid and various forms of amorphous and hydrated silica ("SiO2"). 
At the concentration usually used for water fluoridation, 99% hydrolysis occurs and the pH drops. 
The rate of hydrolysis increases with pH. 
At the pH of drinking water, the degree of hydrolysis is essentially 100%.



The majority of the hexafluosilic acid is converted to aluminium fluoride and synthetic cryolite. 
These materials are central to the conversion of aluminium ore into aluminium metal. 
The conversion to aluminium trifluoride is described as:

H2SiF6 + Al2O3 → 2 AlF3 + SiO2 + H2O

Fluosilic acid is also converted to a variety of useful hexafluorosilicate salts. 
Fluosilic acid is used in the production of porcelains, the magnesium salt for hardened concretes and as an insecticide, and the barium salts for phosphors.
Fluosilic acid and the salts are used as wood preservation agents.
Fluosilic acid along with oxalic acid are the active ingredients used in Iron Out rust-removing cleaning products, which are essentially varieties of laundry sour.

Fluosilic acid is also used as an electrolyte in the Betts electrolytic process for refining lead.
Fluosilic acid is a specialized reagent in organic synthesis for cleaving Si–O bonds of silyl ethers. 
Fluosilic acid is more reactive for this purpose than HF. 
Fluosilic acid reacts faster with t-butyldimethysilyl (TBDMS) ethers than triisopropylsilyl (TIPS) ethers.



-Molecular Weight: 144.091    
-Hydrogen Bond Donor Count: 2    
-Hydrogen Bond Acceptor Count: 6    
-Rotatable Bond Count: 0    
-Exact Mass: 143.98299557    
-Monoisotopic Mass: 143.98299557    
-Topological Polar Surface Area: 0 Ų    
-Heavy Atom Count: 7    
-Formal Charge: 0    
-Complexity: 19.1    
-Isotope Atom Count: 0    
-Defined Atom Stereocenter Count: 0    
-Undefined Atom Stereocenter Count: 0    
-Defined Bond Stereocenter Count: 0    
-Undefined Bond Stereocenter Count: 0    
-Covalently-Bonded Unit Count: 3    
-Compound Is Canonicalized: Yes



-Appearance: Clear colorless Liquid
-Density: 1.22 g/mL at 25 °C
-Boiling Point: 108-109°C
-Flash Point: 108-109°C
-Solubility: Miscible with water



-PSA: 0
-XLogP3: 2.36540
-Appearance: Clear colorless Liquid
-Density: 1.22 g/mL at 25 °C
-Melting Point: No melting point
-Boiling Point: 120 °C (approx)
-Flash Point: 108-109°C
-Refractive Index: 1.35
-Water Solubility: H2O: 1 mg/mL, clear, colorless
-Storage Conditions: −20°C



-Water treatment
-Surface treatment
-Lead refining
-Water fluoridation
-Surface treatment of metals
-In electrolytic refining of lead
-In the manufacture of metallic fluosilicates
-Wood preservative



-Formulation: 35% w/w in water
-Physical State: Liquid
-Storage: Store at room temperature
-Boiling Point: 108-109° C
-Density: 1.22 g/mL



Separated from strong bases and food and feedstuffs. Well closed. 
Stored in a dry, cool, and dark place.
Protected from moisture and avoided exposure to direct sunshine.



fluosilic acid solution
fluosilic acid, 22-25% in water
Fluosilicic acid, purum, 33.5-35%
fluosilic acid solution, AR,30.0-32.0%
fluosilic acid solution, GR,30.0-32.0%
fluosilic acid solution, 20-25 wt. % in H2O

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