Phosphorus Pentoxide-Derived Polyphosphoric Acid

Polyphosphoric acid produced by dissolving diphosphorus pentoxide (P2O5) in phosphoric acid, forming chains of (HPO3)n. It is used in cyclization reactions and as a dehydrating agent, classified in HTS 2809.20.00.40 as polyphosphoric acids.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳ChinaFree+35.0%35%
🇲🇽MexicoFree+10.0%10%
🇨🇦CanadaFree+10.0%10%
🇩🇪GermanyFree+10.0%10%
🇯🇵JapanFree+10.0%10%

Alternative Classifications

This product could be classified differently depending on its characteristics or intended use.

2809.10.00.00Same rate: 35%

If pure P2O5 without hydration to polyacid

Diphosphorus pentaoxide (anhydride form) is classified separately from its hydrated polyacids.

3824.99.39Same rate: 35%

If diluted below purity threshold for chemically defined

Less pure forms may be seen as mixtures or preparations under 3824.

2835.39.10.00Higher: 38.1% vs 35%

If for linear polyphosphates as salts

Sodium or potassium polyphosphates (e.g., for water treatment) are in 2835.

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Import Tips & Compliance

• Provide manufacturing process details or NMR spectra confirming polyphosphoric structure

• Store and ship in moisture-proof containers to prevent hydrolysis to orthophosphoric acid

• Label with exact H3PO4 equivalent percentage for CBP verification