Chamber Process Sulfonitric Acid
Sulfonitric acid produced via the chamber process for sulfuric acid manufacturing, existing primarily as nitrosylsulfuric acid. It is classified in HTS 2808.00.00.20 as a sulfonitric acid, distinct from pure nitric acid under the same heading.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If sodium or ammonium salts dominate the shipment
Chapter Note 5 limits 2826-2842 to metal salts; acid forms stay in 28 but salt conversion changes heading per notes.
If as complex salts or thiocyanates if reacted with inorganic bases
Chapter Note 4 classifies double salts in 2842; sulfonitric derivatives with metals become complex salts.
If for pesticide or herbicide formulations containing sulfonitric acid
Finished pesticide products fall in Chapter 38, not pure chemicals of Chapter 28.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Reference USITC rulings on chamber acid; provide production process documentation to distinguish from 2808.00.00.00 nitric acid
• Classify as Corrosive 8 (UN 1791); require acid-proof packaging and spill containment certifications
Related Products under HTS 2808.00.00.20
Nitrosylsulfuric Acid (HNSO5)
Nitrosylsulfuric acid, also known as chamber acid or sulfonitric acid, is a chemically defined inorganic compound with the formula HNO2SO4 or [NO]+[HSO4]-. It falls under HTS 2808.00.00.20 as a sulfonitric acid, a mixed acid containing both nitric and sulfuric acid functionalities, classified in Chapter 28 for inorganic acids.
Fuming Sulfonitric Acid Mixture
A fuming sulfonitric acid solution combining concentrated nitric acid (HNO3) and sulfuric acid (H2SO4) in nitrosylsulfuric form, used in nitration processes. Classified under HTS 2808.00.00.20 as it meets the definition of sulfonitric acids per Chapter 28 notes for chemically defined inorganic acids.
Industrial Nitrosulfuric Acid Solution 98%
A 98% pure aqueous solution of nitrosylsulfuric acid used in organic synthesis and explosives manufacturing. Falls under HTS 2808.00.00.20 as a chemically defined sulfonitric acid per Chapter 28 definitions, excluding organo-inorganic mixtures.