7664-39-3

Basic information

• Product Name: Hydrogen fluoride
• Synonyms: Rubigine;Fluorwaterstof;Hydrofluoric acid;Fluoric acid;Fluorowodor;hydrogen Fluoride;Hydrofluoride;fluorhydric acid;hydrogen fluorid;HYDROFLUORIC ACID;hydrofluoric;antisal2b
• CAS NO: 7664-39-3
• Molecular Formula: FH
• Molecular Weight: 20.0063432
• EINECS: 231-634-8
• Mol File: 7664-39-3.mol
• Article Data: 179

Chemical Properties

• Melting Point: -35℃
• Boiling Point: 19.538 °C at 760 mmHg
• Flash Point: 112 °C
• Appearance: colourless gas with a pungent odour
• Density: 1.15 g/mL at 25 °C(lit.)
• Vapor Pressure: 922mmHg at 25°C
• Water Solubility: soluble
• CAS DataBase Reference: Hydrogen fluoride(CAS DataBase Reference)
• NIST Chemistry Reference: Hydrogen fluoride(7664-39-3)
• EPA Substance Registry System: Hydrogen fluoride(7664-39-3)

Safety Data

• Hazard Codes: T+:Very toxic
• Statements: R26/27/28:; R35:
• Safety Statements: S26:; S36/37:; S45:; S7/9:
• RIDADR: 1790
• HazardClass: 8
• PackingGroup: I
• Hazardous Substances Data: 7664-39-3(Hazardous Substances Data)

Usage

Description

Hydrogen fluoride, also known as hydrofluoric acid, is a colorless, highly corrosive, and toxic chemical compound that exists in both gaseous and liquid forms. It is a weak acid with a variety of industrial applications due to its unique properties.

Uses

Used in Chemical Industry:
Hydrogen fluoride is used as a raw material for the production of fluorocarbons and other fluoride compounds, which have various applications in the chemical industry.
Used in Aluminum Production:
Hydrogen fluoride is utilized in the smelting process of aluminum, where it serves as a crucial component in the extraction of aluminum from its ores.
Used in Glass Etching:
Hydrogen fluoride is employed as an etching agent in the glass industry, enabling the creation of intricate designs and patterns on glass surfaces.
Used in Uranium Refining:
Hydrogen fluoride plays a key role in the refining of uranium, where it is used to dissolve and purify uranium ore to obtain the desired isotopes.
However, due to its hazardous nature, hydrogen fluoride requires careful handling, storage, and disposal to prevent severe health risks and environmental damage.

InChI:InChI=1/FH/h1H/i/hD

Synthetic route

rubidium fluoride + sodium paratungstate → hydrogen fluoride (7664-39-3)

Conditions	Yield
In melt	100%
In melt	100%

potassium fluoride → hydrogen fluoride (7664-39-3)

Conditions	Yield
With oxalic acid In water byproducts: potassium oxalate; evapn. twice with satd. soln. of oxalic acid;	100%
With oxalic acid In water byproducts: potassium oxalate; evapn. twice with satd. soln. of oxalic acid;	100%
With carbon dioxide In water absorption of CO2 from air;
In water electrodialysis;
With CO2 In water absorption of CO2 from air;

potassium fluoride + sodium paratungstate → hydrogen fluoride (7664-39-3)

Conditions	Yield
In melt	100%
In melt	100%

sodium paratungstate + lithium fluoride → hydrogen fluoride (7664-39-3)

Conditions	Yield
In melt	100%
In melt	100%

sodium paratungstate + sodium fluoride → hydrogen fluoride (7664-39-3)

Conditions	Yield
In melt	100%
In melt	100%

sodium paratungstate + cesium fluoride (13400-13-0) → hydrogen fluoride (7664-39-3)

Conditions	Yield
In melt	100%
In melt	100%

triethyloxonium fluoroborate (368-39-8) + bis(trifluoromethanesulfonyl)amide (82113-65-3) → triethyloxonium bis(trifluoromethylsulfonyl)imide (945614-34-6) + hydrogen fluoride (7664-39-3) + boron trifluoride (7637-07-2)

Conditions	Yield
at 75 - 80℃; for 3h;	A 100% B n/a C n/a

Pentafluoroethyl-(1,2,2,2-tetrafluoro-1-trifluoromethyl-ethyl)-amine (54566-80-2) → perfluoro(4-methyl-3-aza-2-pentene) (2344-11-8) + hydrogen fluoride (7664-39-3)

Conditions	Yield
in presence of (CH3)3N, 25°C, 3 h;	A 99% B n/a
in presence of (CH3)3N, 25°C, 3 h;	A 99% B n/a

triethylsulfonium tetrafluoroborate (368-40-1) + bis(trifluoromethanesulfonyl)amide (82113-65-3) → triethyloxonium bis(trifluoromethylsulfonyl)imide (945614-34-6) + hydrogen fluoride (7664-39-3) + boron trifluoride (7637-07-2)

Conditions	Yield
at 75 - 80℃; for 3h;	A 97.9% B n/a C n/a

triethyloxonium fluoroborate (368-39-8) + H[perfluoroethyltrifluoroborate] → triethyloxonium tris(pentafluoroethyl)trifluorophosphate (945614-32-4) + hydrogen fluoride (7664-39-3) + boron trifluoride (7637-07-2)

Conditions	Yield
at 75 - 80℃; for 3h; Product distribution / selectivity;	A 95.7% B n/a C n/a

N,N'-bis-(trifluoromethyl)tetrafluoroethylene-1,2-diamine (34451-17-7) → perfluoro(2,5-diaza-2,4-hexadiene) (17227-27-9) + hydrogen fluoride (7664-39-3)

Conditions	Yield
70°C, 4 h, in presence of NaF;	A 95% B n/a
70°C, 4 h, in presence of NaF;	A 95% B n/a

calcium fluoride + sulfuric acid (7664-93-9) + water (7732-18-5) → hydrogen fluoride (7664-39-3)

Conditions	Yield
330 to 370°C, CaF2:H2SO4:H2O = 1:1.35:1.8, air as carrier gas, in a fluidized bed;	91%

calcium fluoride + phosphoric acid (86119-84-8, 7664-38-2) → hydrogen fluoride (7664-39-3)

Conditions	Yield
3h, fluorite concentrate (95% CaF2, 1-3% SiO2, 1% H2O);	90%

ammonium hydrogen fluoride + sulfuric acid (7664-93-9) → hydrogen fluoride (7664-39-3)

Conditions	Yield
In water 1.0 atm, 180°C;	88%
In water 1.0 atm, 170°C;	84%
150°C;

fluorine (7782-41-4) + sulfur (7704-34-9) → disulfur decafluoride (5714-22-7) + disulfur difluoride (13709-35-8) + sulfur tetrafluoride (7783-60-0) + hydrogen fluoride (7664-39-3) + sulfur(VI) hexafluoride (2551-62-4)

Conditions	Yield
In neat (no solvent) byproducts: OF2; introduction of F2 into steel chamber, sulfur in compartments; detailed description of apparatus and handling given;; first passing through Ni (or Monel) tube (400°C); second Cu column (H2O sprayed); passed into steel column (containing carbon/Fe shavings; aq. NaOH sprayed); dried in column (containing solid NaOH, BaO or P2O5);;	A n/a B n/a C n/a D n/a E 87%

(C5Me5)Rh(PMe3)(H)2 (84624-03-3) + decafluorobiphenyl (434-90-2) → (C5Me5)Rh(PMe3)(4-perfluorobiphenyl)H (194661-76-2) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In perdeuteriopyridine (N2); thermolysis (85°C) with 12 equiv of perfluorobiphenyl;	A 87% B n/a

tetracyanidoboronic acid (623575-99-5) + triethyloxonium fluoroborate (368-39-8) → triethyloxonium tetracyanoborate (945614-35-7) + hydrogen fluoride (7664-39-3) + boron trifluoride (7637-07-2)

Conditions	Yield
at 75 - 80℃; for 3h;	A 85.4% B n/a C n/a

(C5Me5)Rh(PMe3)(H)2 (84624-03-3) + Hexafluorobenzene (392-56-3) → (C5(CH3)5)Rh(P(CH3)3)(C6F5)H (194661-74-0) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In perdeuteriopyridine (N2); thermolysis (85°C) with 12 equiv of C6F6;	A 81% B n/a

calcium fluoride + water (7732-18-5) + silica gel (112926-00-8, 7631-86-9) → wollastonite + hydrogen fluoride (7664-39-3)

Conditions	Yield
1925 to 2760°C, hydrothermal process;	A n/a B 80%

methanol (67-56-1) + chlorosulfonyldifluoroacetylfluoride (2561-57-1) → methyl 2,2-difluoro-2-(chlorosulfonyl)acetate (18225-68-8) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In dichloromethane 20°C;	A 80% B n/a

xenon difluoride (13709-36-9) + bis(fluorosulfonyl)amide (14984-73-7) → fluoro[imidobis(sulfuryl fluoride)]xenon(II) (53719-78-1) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In Dichlorodifluoromethane 3 d at 0°C, 1:1 molar ratio; The reactor was pumped for 3 h at 0°C to remove the byproducts, elem. anal.;	A 80% B n/a

ethanol (64-17-5) + chlorosulfonyldifluoroacetylfluoride (2561-57-1) → Chlorsulfonyl-difluoressigsaeure-ethylester (18328-81-9) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In dichloromethane 20°C;	A 75% B n/a

perhydrodibenzo-18-crown-6 (16069-36-6) + cis-anti-cis-dicyclohexano-18-crown-6 boron trifluoride monohydrate complex + water (7732-18-5) → C20H36O6*H3O(1+)*BF4(1-)=C20H36O6*H3O(1+)*BF4(1-) + hydrogen fluoride (7664-39-3) + boric acid (11113-50-1)

Conditions	Yield
In methanol standing at 20°C to solvent evapn.; residue dilution with acetone/hexane, soln. partial evapn., upper layer decanting, residue washing with hot hexane, crystn. from ethyl acetate;	A 71% B n/a C n/a

mesityltrifluorogermane (136948-87-3) → difluorodimesitylgermane (96481-36-6) + (GeF2CH2C6H2(CH3)2)2 (136948-90-8) + hydrogen fluoride (7664-39-3) + germanium tetrafluoride (7783-58-6)

Conditions	Yield
In benzene byproducts: C6H3(CH3)3; (N2); soln. of Ge-compd. in anhyd. benzene kept at 80°C (12 h);;	A 30% B 70% C n/a D n/a

Bis(ethylthio)(1,2,2,2-tetrafluoroethylidene)methane (145327-75-9) + 2,3-dimethyl-buta-1,3-diene (513-81-5) → (2-trifluoromethyl-4,5-dimethylphenyl)ethylsulfide (1400258-81-2) + hydrogen fluoride (7664-39-3) + ethanethiol (75-08-1)

Conditions	Yield
In 1-methyl-pyrrolidin-2-one at 190℃; Diels-Alder Cycloaddition;	A 63% B n/a C n/a

calcium fluoride → hydrogen fluoride (7664-39-3)

Conditions	Yield
With sulfuric acid byproducts: PbF2, SiF4, HSO3F; concd. H2SO4; water content 5 %, water content is higher if diluted H2SO4 is used; 185 °C, 4 h; H2SO3 also formed;;	60%
With H2SO4 byproducts: PbF2, SiF4, HSO3F; concd. H2SO4; water content 5 %, water content is higher if diluted H2SO4 is used; 185 °C, 4 h; H2SO3 also formed;;	60%
With calcium sulfate; sulfuric acid

cryolite → hydrogen fluoride (7664-39-3)

Conditions	Yield
With sulfuric acid byproducts: PbF2, SiF4, HSO3F; concd. H2SO4; water content 5 %, water content is higher if diluted H2SO4 is used; 185 °C, 4 h; H2SO3 also formed;;	60%
With H2SO4 byproducts: PbF2, SiF4, HSO3F; concd. H2SO4; water content 5 %, water content is higher if diluted H2SO4 is used; 185 °C, 4 h; H2SO3 also formed;;	60%
With sulfuric acid heating in Pb- or Pt- containers; concd. H2SO4;;

Bis(ethylthio)(1,2,2,3,3,3-hexafluoropropylidene)methane (145327-77-1) + 2,3-dimethyl-buta-1,3-diene (513-81-5) → (2-pentafluoroethyl-4,5-dimethylphenyl)ethylsulfide (1400258-82-3) + hydrogen fluoride (7664-39-3) + ethanethiol (75-08-1)

Conditions	Yield
In 1-methyl-pyrrolidin-2-one at 190℃; for 40h; Diels-Alder Cycloaddition;	A 60% B n/a C n/a

calcium fluoride + water (7732-18-5) → hydrogen fluoride (7664-39-3) + calcium oxide

Conditions	Yield
In neat (no solvent) passing a slow water-steam-stream over heated CaF2 in a platinum-tube gives an equilibrium; messure of Vol-% HF at different temperatures;;	A 52.9% B n/a
In neat (no solvent) passing a slow water-steam-stream over heated CaF2 in a platinum-tube gives an equilibrium; messure of Vol-% HF at different temperatures;;	A 52.9% B n/a

trans-WOF4CH3CN (39687-62-2) + water (7732-18-5) → WOF5(1-) (32573-14-1) + W2O2F8(OH)(1-) + mer-WOF3(OH)CH3CN (60670-09-9) + W2O2F9(1-) + hydrogen fluoride (7664-39-3)

Conditions	Yield
In water; acetonitrile byproducts: trans-WOF4(H2O); addn. of 3.5% H2O as a 20% soln. of water in CH3CN to a soln. of trans-XOF4(CH3CN) in acetonitrile;; not isolated; detected by 19F-NMR-spectroscopy;;	A 2.5% B 7.5% C 50% D 5% E 30%

sodium nitrate (7631-99-4) + hydrogen fluoride (7664-39-3) → sodium fluoride

Conditions	Yield
20 min, 250 °C;;	100%
20 min, 250 °C;;	100%

2,2,4,4,6,6-hexachloro-1,3,5-triaza-2,4,6-triphosphorine (940-71-6) + hydrogen fluoride (7664-39-3) → hydrogenchloride (7647-01-0) + ammonium hexafluorophosphate

Conditions	Yield
In not given react. with HF;;	A n/a B 100%

osmium pentafluoride oxide (19184-41-9) + hydrogen fluoride (7664-39-3) → osmium tetrafluoride oxide (38448-58-7)

Conditions	Yield
Dry HF and OsOF5 were condensed into a reaction vessel. The reactor was heated to 293 K.; HF and the excess of OsOF5 were driven off by heating the reaction products to constant weight. Crystalline ReOF4 was separated from the green solution. Elem. anal.;	100%

rhenium oxide pentafluoride (23377-53-9) + hydrogen fluoride (7664-39-3) → rhenium oxotetrafluoride (17026-29-8, 52152-11-1)

Conditions	Yield
Dry HF and ReOF5 were condensed into a reaction vessel. The reactor was then heated to 293 K.; HF and the excess of ReOF5 were driven off by heating the reaction products to constant weight. Crystalline ReOF4 was separated from the blue solution. Elem. anal.;	100%

hydrogen fluoride (7664-39-3) + tantalum pentachloride (7721-01-9) + lithium fluoride → LiTaF6

Conditions	Yield
In neat (no solvent) heating (HF atm., 200°C, 2 h); elem. anal.;	100%

[Mo2(η5-C5Me5)2(μ-S)(μ-SMe)2(CO)2] + hydrogen fluoride (7664-39-3) → [((CH3)5C5)Mo(CO)(SCH3)]2(SH)(1+)*Br(1-)=[[((CH3)5C5)Mo(CO)(SCH3)]2(SH)]Br

Conditions	Yield
In dichloromethane N2 or Ar-atmosphere; pptn. on concg. and Et2O addn., filtering, washing (pentane);	100%

bis(tetra(n-butyl)ammonium)-di(nitro(N))phthalocyaninato(2-)ruthenate(II) + hydrogen fluoride (7664-39-3) → [RuF(C6H4N2C2)4(NO)]

Conditions	Yield
In tetrahydrofuran; hydrogen fluoride byproducts: NO2(1-); addn. of conc. aq. HX, boiling (15 min); cooling, crystn., washing (H2O), drying (vac.);	100%

indium(I) tetrafluoroborate (62792-13-6) + hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) → indium(I) hexafluoroantimonate (877238-63-6)

Conditions	Yield
In hydrogen fluoride HF (liquid); equimol., HF condenced onto reagent at 77 K, alowed to warm to room temp., left for 1 d; volatiles removed (vac.); elem. anal.;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + acetonitrile (75-05-8) → C2H3N*F6Sb(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: acetonitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + acetonitrile (75-05-8) → MeCNHSb2F11

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: acetonitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + propiononitrile (107-12-0) → C3H5N*F6Sb(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: propiononitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + propiononitrile (107-12-0) → C3H5N*F11Sb2(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: propiononitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

propyl cyanide (109-74-0) + hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) → C4H7N*F6Sb(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: propyl cyanide at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

propyl cyanide (109-74-0) + hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) → C4H7N*F11Sb2(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: propyl cyanide at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + benzonitrile (100-47-0) → C7H5N*F6Sb(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: benzonitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + benzonitrile (100-47-0) → C7H5N*F11Sb2(1-)*H(1+)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride at -196 - 20℃; Sealed tube; Stage #2: benzonitrile at -196 - 20℃; for 0.5h; Sealed tube; Inert atmosphere;	100%

ferrocene (102-54-5) + hydrogen fluoride (7664-39-3) + phosphorus pentafluoride (7647-19-0, 874483-74-6) → C10H11Fe(1+)*F6P(1-)

Conditions	Yield
at -196 - 20℃; Sealed tube;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + malononitrile (109-77-3) → C3H3N2(1+)*F6Sb(1-)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride Schlenk technique; Inert atmosphere; Cooling; Stage #2: malononitrile for 0.0833333h; Schlenk technique; Inert atmosphere; Cooling;	100%

hydrogen fluoride (7664-39-3) + antimony pentafluoride (7783-70-2) + malononitrile (109-77-3) → C3H4N2(2+)*2F6Sb(1-)

Conditions	Yield
Stage #1: hydrogen fluoride; antimony pentafluoride Schlenk technique; Inert atmosphere; Cooling; Stage #2: malononitrile for 0.0833333h; Schlenk technique; Inert atmosphere; Cooling;	100%

hydrogen fluoride (7664-39-3) + sulphamoyl chloride (7778-42-9) + germanium tetrafluoride (7783-58-6) → 2ClH2NO2S*2H(1+)*F6Ge(2-)

Conditions	Yield
at -196 - -40℃; for 72h; Schlenk technique;	100%

Upstream product

• 64-19-7 acetic acid 
• 67-56-1 methanol 
• 462-06-6 fluorobenzene 
• 76-04-0 2-chloro-2,2-difluoroacetic acid 
• 71-43-2 benzene 
• 381-59-9 methyl difluoroborinate 
• 7732-18-5 water 
• 75-71-8 Dichlorodifluoromethane 
• 401-75-2 trifluoromethylcyclohexane 
• 352-36-3 silicon trifluoro monoisocyanate 
• 358-80-5 silicon difluoro diisocyanate 
• 358-59-8 silicon monofluoro triisocyanate 
• 359-25-1 bromo-fluoroacetic acid 
• 372-46-3 fluorocyclohexane 

Downstream Products

• 675-14-9 trifluoro-[1,3,5]triazine 
• 696-85-5 2-chloro-4,6-difluoro-[1,3,5]triazine 
• 696-84-4 2,4-dichloro-6-fluoro-[1,3,5]triazine 
• 694-52-0 4-fluoropyridine 
• 3881-38-7 1-(4'-pyridyl)-4-pyridone 
• 103-30-0 (E)-1,2-diphenyl-ethene 
• 459-72-3 ethyl 2-fluoroacetate 
• 131-09-9 2-chloroanthracene-9,10-dione 
• 28537-93-1 1,1-di-p-tolyl-1-deoxy-D-glucitol 
• 108844-65-1 5-p-tolyl-1,5-anhydro-D-mannitol 
• 514-36-3 fludrocortisone acetate 
• 96843-89-9 21-acetoxy-11β,17-dihydroxy-pregna-4,8(14)-diene-3,20-dione 
• 107058-89-9 6A-(2-hydroxy-ethoxy)-4-(4-methoxy-phenyl)-hexahydro-cyclopenta[b]furan-2-one 
• 408317-31-7 cyclohexane-1,3,5-trione-tris-diethylacetal 

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