CAS 7782-78-7 · Nitrosylsulfuric Acid

Nitrosylsulfuric Acid: direct from source to Europe

Nitrosylsulfuric Acid (CAS 7782-78-7) is a corrosive, fuming liquid or low-melting solid, typically supplied as a solution in sulfuric acid, used as a diazotisation and nitrosation reagent in dye, pigment and pharmaceutical synthesis.

  • COA, SDS & TDS with every batch
  • REACH status confirmed before quote
  • Samples available for qualification
Purityup to 98%+Assay, premium grade
Lead time3 – 6 weeksOrigin to European port
FormLiquid (fuming)Drums to ISO tank
Response1 business dayQuotation after receiving your spec
Product identification

Nitrosylsulfuric Acid: names, synonyms and identifiers

Buyers search for this material under several names. Whichever one appears on your specification, purchase order or REACH dossier, it is the same compound: Nitrosylsulfuric Acid, CAS 7782-78-7.

  • Confirmed CAS number on every COA
  • Premium grade with assay 98%+ available
  • TDS and SDS supplied with every shipment
Common name
Nitrosylsulfuric Acid
Synonyms
Nitrosylsulphuric acid · Nitrosonium bisulfate · NOHSO4
CAS number
7782-78-7
Formula / MW
NOHSO4  /  127.08 g/mol
Chemical family
Diazotisation and nitrosation reagent
HS code
2811 (other inorganic acids). Confirm the full code with your broker.

⚠ Often supplied as a solution in sulfuric acid rather than the neat compound; always confirm the strength you need together with CAS 7782-78-7.

Technical data

Nitrosylsulfuric Acid physical and chemical properties

Key parameters for process engineering, safety planning and storage design. Values are typical; always verify against the current TDS for your lot.

Appearance
Yellow to brown fuming liquid or paste
Colour depends on concentration
Melting point
Approx. 73 °C (neat)
Usually handled as a sulfuric acid solution, liquid at room temperature
Boiling point
Decomposes on heating
Releases NOx and SO₃ fumes
Molecular weight
127.08
g/mol
Molecular formula
NOHSO4
Diazotisation and nitrosation reagent
Solubility
Reacts with water
Hydrolyses to sulfuric and nitrous/nitric acid
Density
Approx. 1.83–1.90 g/cm³
Depends on concentration
Storage
Sealed, dry, vented containers
Acid-resistant, moisture-excluded storage
Quality & specification

Nitrosylsulfuric Acid grade specifications: standard vs premium

Two grades are offered so your process chemist or quality team can pick what suits downstream requirements. COA parameters are confirmed before every shipment.

Parameter
Standard grade
Premium grade
Test method / note
Assay (NOHSO₄)
≥ 96.0%
≥ 98.0%
Titration
Free sulfuric acid
≤ 3.0%
≤ 1.5%
Titration
Insoluble matter
≤ 0.10%
≤ 0.05%
Gravimetric
Colour
Yellow to brown
Yellow to brown
Visual check
Appearance
Fuming liquid or paste
Fuming liquid or paste
Visual check

All values are specification limits, not guaranteed minima. Actual COA figures for your lot are provided before dispatch. Non-standard specifications are available on enquiry.

Applications

Where Nitrosylsulfuric Acid is used

Typical end uses and synthesis routes for European manufacturers, toll processors and laboratories.

Diazotisation reagent

Generates diazonium salts directly from aromatic amines without separate nitrite addition.

Nitrosation chemistry

Reagent for N-nitroso and C-nitroso compound synthesis.

Dye and pigment synthesis

Used in azo dye and pigment manufacture where in-situ nitrosyl sulfuric acid generation is preferred.

Custom synthesis

Reagent for contract synthesis at industrial scale, for verified users only.

Packaging & logistics

Packed to your site, documented for customs

Nitrosylsulfuric Acid is handled as a dangerous good. Every shipment leaves with UN-approved packaging, CLP labelling and the full document set for European import.

Drums

Lined steel drums

UN-approved acid-resistant lined steel drums with vented, sealed closures.

Up to 250 kg net
IBC

IBC / ISO tank

UN-approved acid-rated IBCs or ISO tank containers for higher-volume users.

On request
Bulk

Bulk supply

Bulk supply packed to agreement for suitable receiving sites.

On request
Document set included: Bill of lading · Commercial invoice · Packing list · Certificate of analysis (COA) · Safety data sheet (SDS) · Dangerous goods declaration (IMDG/ADR) · Certificate of origin · Other certificates on request
Common questions

Nitrosylsulfuric Acid: frequently asked questions

Quick answers for European buyers. For anything else, email source@cheloragroup.com.

It is also sold as Nitrosylsulphuric acid, Nitrosonium bisulfate, NOHSO4. All refer to CAS 7782-78-7. Confirm the CAS number with any supplier before ordering.

Price depends on grade, volume, packing, Incoterm and destination port, and moves with raw material markets. Send us your requirement and we will quote in EUR or USD with a landed-cost breakdown, usually within one business day.

Nitrosylsulfuric Acid (CAS 7782-78-7) is a corrosive, fuming liquid or low-melting solid, typically supplied as a solution in sulfuric acid, used as a diazotisation and nitrosation reagent in dye, pigment and pharmaceutical synthesis.

Standard grade offers 96.0% minimum assay. Premium grade offers 98.0% minimum with lower free sulfuric acid and insoluble matter. Premium is recommended for diazotisation routes needing consistent, reproducible reactivity.

It is normally supplied as a concentrated solution in sulfuric acid, since the neat compound is a low-melting solid that is awkward to handle and transport. Tell us the strength and volume you need and we will confirm what we can supply. Order by CAS (7782-78-7).

Nitrosylsulfuric Acid is corrosive and can generate toxic nitrogen oxide fumes on decomposition or contact with water, and can face REACH, CLP and transport obligations depending on use. We confirm the current status for your application before quoting.

Store in sealed, vented, acid-resistant containers under dry conditions, away from water, organics, reducing agents and combustible materials, in a dedicated, access-controlled area.

It is a corrosive and oxidising dangerous good (class and UN number per SDS, commonly Class 8; always confirm on the current SDS). We pack it in UN-approved, moisture-excluded containers, apply CLP labels and ship through licensed forwarders under IMDG for sea and ADR for European road.

Yes. Laboratory and pilot samples are supplied with a COA and SDS so your team can qualify the grade. Mention sample needs in your enquiry.

REACH status is confirmed before we quote. We advise on importer-of-record arrangements and whether the substance is registered for your use. Send your use descriptor and we will confirm.

Ready to source?

Get your Nitrosylsulfuric Acid quotation today

Send us the grade, volume, destination and Incoterm. You will receive a clear price, packaging options and a full document checklist, usually within one business day.

  • Samples to full containers
  • COA, SDS and DG documents included as standard
  • Quote in EUR or USD, your choice of Incoterm