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Phosphorus Pentoxide-Derived Polyphosphoric Acid from Mexico

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.

Duty Rate — Mexico → United States

10%

Rate breakdown

9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico

Import Tips

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