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Magnesium Sulfite Tribasic

Tribasic magnesium sulfite (Mg3(SO3)2) used in pharmaceutical buffering and flame retardants. Classified in HTS 2832.20.00.00 as a chemically defined sulfite salt of an inorganic base.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳China3.1%+35.0%38.1%
🇲🇽Mexico3.1%+10.0%13.1%
🇨🇦Canada3.1%+10.0%13.1%
🇩🇪Germany3.1%+10.0%13.1%
🇯🇵Japan3.1%+10.0%13.1%

Alternative Classifications

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

2835.29Lower: 14.1% vs 38.1%

If magnesium phosphite

Phosphites are in 2835, separate from sulfites in Chapter 28.

2815Lower: 13.7% vs 38.1%

If magnesium hydroxide form

Hydroxides classified earlier in subchapter II.

3824.99Lower: 15% vs 38.1%

If in flame retardant mixtures

Commercial preparations for retail or industrial use fall outside pure compounds.

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Import Tips & Compliance

• GMP certification required for pharma grades; non-certified may face FDA detention

• Specify basicity level (tribasic); ambiguous descriptions lead to 2835 classification errors

• Monitor for asbestos contamination in natural-derived sources during inspections

Related Products under HTS 2832.20.00.00

Sodium Sulfite Anhydrous

Sodium sulfite (Na2SO3) in anhydrous form is a white crystalline powder used as a reducing agent and preservative. It falls under HTS 2832.20.00.00 as one of the 'other sulfites' excluding sodium and potassium sulfites, which are specified separately in the tariff schedule.

Ammonium Sulfite Solution 40%

A 40% aqueous solution of ammonium sulfite ((NH4)2SO3) used in wastewater treatment and as an oxygen scavenger. Classified under HTS 2832.20.00.00 as an 'other sulfite' of an inorganic base, meeting Chapter 28 definitions for chemically defined compounds.

Zinc Sulfite Powder

Zinc sulfite (ZnSO3) powder used in specialty chemical synthesis and as a corrosion inhibitor. It qualifies under HTS 2832.20.00.00 as a sulfite of an inorganic base (metal salt), distinct from chromates or other excluded compounds.

Calcium Sulfite Hemihydrate

Calcium sulfite hemihydrate (CaSO3·0.5H2O), a white powder byproduct from flue gas desulfurization, used in construction materials. Falls under HTS 2832.20.00.00 as an 'other sulfite' chemically defined per Chapter 28 Note 1.

Ferrous Sulfite Crystals

Ferrous sulfite (FeSO3) crystals employed in analytical chemistry and reducing applications. Meets HTS 2832.20.00.00 criteria as an 'other sulfite' of iron, chemically defined inorganic compound.

Strontium Sulfite Powder

Strontium sulfite (SrSO3) powder for pyrotechnics and specialty ceramics. Under HTS 2832.20.00.00 as a rare earth-adjacent sulfite, excluded from radioactive elements in 2844.