Zinc Phosphate Dihydrate
Zinc phosphate dihydrate (Zn3(PO4)2·2H2O) is a fine white powder used as a corrosion inhibitor in metal primers and as a component of dental cements. It is a chemically defined zinc salt of phosphoric acid, falling under the 'other phosphates' provision of tariff item 2835.29.00. The product is not a polyphosphate or a phosphonate, so it is correctly classified here.
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 a polyphosphate (e.g., zinc polyphosphate) rather than a simple orthophosphate
Polyphosphates are classified separately in subheading 2835.39, which covers 'other polyphosphates'.
If the zinc phosphate is part of a formulated anti-corrosion preparation with other active ingredients
Preparations containing zinc phosphate as one component among others may fall under chemical products and preparations of Chapter 38.
If the zinc phosphate dihydrate is specifically put up as a dental cement for retail sale
Dental cements and other dental fillings are classified in heading 30.06, which takes precedence over Chapter 28 by Section VI Note 2.
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
• Ensure the product is clearly labelled as chemically defined zinc phosphate dihydrate with the CAS number (7779-90-0) on the commercial invoice to support classification
• Verify the MFN duty rate for tariff item 2835.29.00, as rates can change; check the CBSA tariff browser before shipping
• If the powder is mixed with other substances (e.g
• pigments or fillers), it may no longer qualify as a separate chemically defined compound, so confirm the composition with your supplier
Related Products under Tariff item 2835.29.00
Aluminum Hydrogen Phosphate
Aluminum hydrogen phosphate (Al(H2PO4)3) is an acidic phosphate salt used as a reactive binder in acid-cured refractories and corrosion inhibitors. It is a separate chemically defined compound, which falls under the 'Other' phosphates of tariff item 2835.29.00.
Aluminum Orthophosphate Powder
Aluminum orthophosphate powder (AlPO4) is a thermally stable, chemically defined compound used in ceramic glazes, dental cements, and optical coatings. As a phosphate of aluminum, it is classifiable under the 'Other' phosphates of this tariff item.
Aluminum Phosphate Gel
Aluminum phosphate gel (AlPO4·2H2O) is a colloidal suspension of a chemically defined aluminum phosphate, used as a binder in refractory ceramics and catalyst supports. The gel form is a dispersion of the compound, which remains classifiable under the 'Other' phosphates of this tariff item.
Anhydrous Trisodium Phosphate Powder
Anhydrous trisodium phosphate powder (Na3PO4) is a chemically defined strong base used in metal pretreatment and food processing as an acidity regulator. It falls under the 'Other' phosphates of this tariff item.
Diammonium Phosphate
Diammonium phosphate ((NH4)2HPO4) functions as a fire retardant, yeast nutrient in baking, and pH buffer. As a chemically defined ammonium salt of phosphoric acid, it is classifiable under tariff item 2835.29.00 as an 'other' phosphate.
Disodium Phosphate Anhydrous
Disodium phosphate anhydrous (Na2HPO4) is a sodium salt of phosphoric acid used in dairy processing, pharmaceuticals, and as a pH buffer. It is a chemically defined inorganic compound and is classifiable under tariff item 2835.29.00 as an 'other' phosphate.