Diphosphorus Tetroxide
Diphosphorus tetroxide (P2O4) is a white hygroscopic solid used as a phosphorylating agent in chemical synthesis. It is classified under tariff item 2811.19.00 as an 'other inorganic oxygen compound of non-metals' because it is a separate chemically defined oxide of phosphorus, not specifically named elsewhere in Chapter 28.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the product is phosphoric acid or polyphosphoric acids
Phosphoric acids are specifically classified in heading 28.09.
If the product is a halide oxide of phosphorus rather than an oxygen compound
Halide oxides of carbon are in heading 28.12, but other non-metal halide oxides may fall in heading 28.12 as well.
If the product is a mixture of phosphorus oxides
Mixtures not meeting the definition of a separate chemically defined compound are classified in Chapter 38.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Diphosphorus tetroxide is hygroscopic and must be shipped in airtight, moisture-proof containers; include this information in the commercial invoice
• The CBSA may request a certificate of analysis to confirm the chemical identity and purity
• Verify that the product is not a mixture with other phosphorus oxides, which would change the classification
Related Products under Tariff item 2811.19.00
33% Hydrobromic Acid in Acetic Acid
A 33% hydrobromic acid solution in glacial acetic acid is a chemically defined inorganic acid, but the solvent is not water. Under Chapter Note 1(c), it qualifies if the acetic acid is a normal and necessary method of putting up for safety or transport and does not render the product suitable for specific use.
48% Hydrobromic Acid Solution
A 48% aqueous solution of hydrogen bromide gas (HBr) is a chemically defined inorganic acid in water. It is classified under this tariff item as an other inorganic acid of a non-metal, per Chapter Note 1(b).
Anhydrous Hydrobromic Acid Gas Cylinder
Anhydrous HBr gas in steel cylinders is a chemically defined inorganic acid in gaseous form. It is classified under this tariff item as an other inorganic acid of a non-metal, as it is not excluded by Chapter Notes.
Anhydrous Sulfamic Acid Flakes
Anhydrous sulfamic acid flakes are a dry, crystalline form of sulfamic acid (H3NSO4) used for analytical chemistry and laboratory reagent applications. It is classified under tariff item 2811.19.00 as an 'other inorganic acid' because it is a separate chemically defined compound of sulfur, nitrogen, hydrogen and oxygen.
Antimonic Acid Colloidal
Colloidal antimonic acid (HSbO3·nH2O) used in flame retardants and catalysts. It is an inorganic oxygen compound of a non-metal, chemically defined despite its colloidal form, and classifiable under this tariff item as an 'other inorganic acid'.
Arsenic Acid Anhydride Powder
Anhydrous arsenic acid powder, also known as arsenic pentoxide when dehydrated, is a chemically defined inorganic compound used in electronics etching. It is classified as an inorganic acid of a non-metal under Chapter 28, meeting the criteria of Note 1(a) to Chapter 28.