Sulfur Trioxide
Sulfur trioxide (SO₃), used in sulfonation and as sulfuric acid dehydrating agent. As the anhydride form, it's an inorganic oxygen compound of sulfur under HTS 2811.29.5000. Supplied stabilized.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If hydrated to sulfuric acid
Sulfuric acid (H₂SO₄) classified separately under 2807.
If oleum (fuming sulfuric acid)
Oleum mixtures fall under preparations if >100% H₂SO₄ equivalent.
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Import Tips & Compliance
• UN 1831; corrosive liquid; stainless steel containers only
• Stabilizer content declaration prevents 2807 classification
• Moisture exclusion critical during transit
Related Products under HTS 2811.29.50.00
Silicon Dioxide (Amorphous Silica)
Amorphous silicon dioxide, also known as synthetic silica, is a chemically defined inorganic oxygen compound of the nonmetal silicon. It falls under HTS 2811.29.5000 as 'other inorganic oxygen compounds of nonmetals' excluding specified compounds like carbon oxides. Used as a filler in rubber, plastics, and pharmaceuticals.
Boron Trioxide (Boric Oxide)
Boron trioxide (B₂O₃) is a pure inorganic oxygen compound of the nonmetal boron, used in glass manufacturing and as a flux. Classified in HTS 2811.29.5000 as an 'other' inorganic oxygen compound of nonmetals per Chapter 28 notes. It appears as a colorless glassy solid.
Phosphorus Pentoxide
Phosphorus pentoxide (P₄O₁₀), also called phosphoric anhydride, is a white powder used as a desiccant and dehydrating agent. It qualifies under HTS 2811.29.5000 as an other inorganic oxygen compound of the nonmetal phosphorus. Highly reactive with water to form phosphoric acid.
Arsenic Trioxide
Arsenic trioxide (As₂O₃), a white powder used in pharmaceuticals and glass production, is an inorganic oxygen compound of nonmetal arsenic. Falls under HTS 2811.29.5000 per chapter definitions excluding specified compounds. Highly toxic, requiring special handling.
Antimony Trioxide
Antimony trioxide (Sb₂O₃) serves as a flame retardant in plastics and a catalyst in PET production. Classified as an other inorganic oxygen compound of nonmetal antimony under HTS 2811.29.5000. Fine white powder form.
Tellurium Dioxide
Tellurium dioxide (TeO₂) used in optical glass and electroceramics is an inorganic oxygen compound of nonmetal tellurium. Fits HTS 2811.29.5000 as other such compounds. Available as white crystalline powder.