Fluorosulfonic acid
Fluorosulfonic acid (CAS: 7789-21-1, FSO3H) is a potent, fuming liquid with a molar mass of 100.07 g/mol. It is a highly corrosive and strong acid, widely recognised for its exceptional ability to act as a powerful solvent and catalyst in various chemical reactions. Its properties make it a critical reagent in organic synthesis and industrial chemical processes, particularly where highly acidic conditions are required.
- IUPAC
- Fluosulfuric acid
Catalysis in Organic Synthesis
Fluorosulfonic acid serves as a potent catalyst in numerous organic transformations, including alkylation, acylation, and isomerisation reactions, owing to its strong Lewis acidity and ability to generate carbocations.
Reagent for Sulfonation
It is employed as a highly effective sulfonating agent, enabling the introduction of the sulfonic acid group (-SO3H) into organic molecules, which is vital for producing dyes, pharmaceuticals, and surfactants.
Specialty Solvent
Due to its aggressive nature and high polarity, fluorosulfonic acid can act as a specialised solvent for certain inorganic and organic compounds that are insoluble in common solvents.
Electronic Chemical Intermediate
Within the microelectronics industry, it is utilised in specialised etching processes and as a component in formulations for semiconductor manufacturing, leveraging its corrosive and conductive properties.
| Molecular weight | 100.07 |
|---|---|
| Linear formula | FSO3H |
| Boiling point | 165.5 °C(lit.) |
| Density | 1.726 g/mL at 25 °C(lit.) |
| Vapour pressure | 2.5 mmHg (25 °C) |
| Vapour density | 3.5 (vs air) |
| Storage temperature | 2-8°C |
| Melting point | −87.3 °C(lit.) |
Hazard statements
- H314Causes severe skin burns and eye damage
- H332Harmful if inhaled
Precautionary statements
- P280Wear protective gloves, clothing and eye/face protection
- P305IF IN EYES
- P310Immediately call a POISON CENTER or doctor
| Protective equipment | Faceshields, full-face respirator (US), Gloves, Goggles, multi-purpose combination respirator cartridge (US), type ABEK (EN14387) respirator filter |
|---|---|
| Transport (UN / ADR) | UN 1777 8 / PGI |
| Water hazard class (WGK, DE) | 1 |
| Hazard codes (EU) | C |
| Risk statements (R) | 20-35 |
| Safety statements (S) | 26-45 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
| Purified By | triple-distillation |
|---|
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Fluorosulfonic acid used for?
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Fluorosulfonic acid is primarily used as a potent catalyst and sulfonating agent in organic synthesis, a specialty solvent, and in the microelectronics industry for etching processes.
What is the CAS number and chemical formula for Fluorosulfonic acid?
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The CAS number for Fluorosulfonic acid is 7789-21-1, and its chemical formula is FSO3H.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Fluorosulfonic acid purified by triple-distillation. As this is a technical/research grade material, TSS does not represent it as USP, BP, or EP grade.
How should Fluorosulfonic acid be handled safely?
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Fluorosulfonic acid is extremely corrosive and causes severe skin burns and eye damage (H314). It is also harmful if inhaled (H332). Handling requires full protective equipment including a faceshield, gloves, goggles, and appropriate respiratory protection (e.g., type ABEK respirator filter). Always consult the Safety Data Sheet before use.
How is Fluorosulfonic acid packed and shipped?
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Fluorosulfonic acid is classified as UN 1777, Hazard Class 8, Packing Group I. It is shipped with extreme care, adhering to all international regulations for corrosive and hazardous materials. Storage temperature is recommended between 2-8°C.
How can I request a sample or quote for Fluorosulfonic acid?
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To request a sample or obtain a quote for Fluorosulfonic acid, please contact our sales team through the website or by phone, providing your specific requirements and delivery details.
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