Zinc Dithionite
Zinc dithionite (ZnS2O4) is an inorganic salt used in industrial reducing applications, particularly in pulp and paper bleaching. Classified under HTS 2831.90.00.00 as 'other' dithionites, it meets Chapter 28 requirements for chemically defined inorganic sulfur-oxygen compounds. Its metal salt nature distinguishes it from organic-stabilized forms.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If when commercially stabilized with organic amines or alcohols
Organic stabilization explicitly moves dithionites to 2831.10 per chapter note 2.
If complexed with other inorganic bases forming double salts
Chapter note states double or complex salts of inorganic bases classify in 2842.
If imported in aqueous solution or with additives exceeding 5% composition
Solutions or preparations not meeting 'chemically defined' criteria fall to Chapter 38.
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Import Tips & Compliance
• Provide assay reports confirming dithionite content >90% to avoid reclassification as mixtures under Chapter 38
• Comply with EPA TSCA registration for new chemical substances if not previously imported
• Label as 'corrosive to metals' per GHS; ensure UN-approved packaging for transoceanic shipment
Related Products under HTS 2831.90.00.00
Sodium Dithionite
Sodium dithionite (Na2S2O4), also known as sodium hydrosulfite, is a white crystalline powder used as a reducing agent in textile bleaching and vat dyeing processes. It falls under HTS 2831.90.00.00 as one of the 'other' dithionites specified in the chapter notes for Chapter 28. This chemically defined inorganic compound is stabilized for industrial use but classified here rather than under organic-stabilized variants.
Potassium Dithionite
Potassium dithionite (K2S2O4) serves as a strong reducing agent in chemical synthesis and wastewater treatment. It is categorized under HTS 2831.90.00.00 for other dithionites, as a chemically defined inorganic compound per Chapter 28 Note 1. Primarily supplied as technical grade powder for industrial applications.
Ammonium Dithionite Solution
Ammonium dithionite (NH4)2S2O4 in aqueous solution acts as a reducing bleach for textiles and paper. Falls under HTS 2831.90.00.00 as 'other' dithionites when chemically defined and not organically stabilized. Concentration typically 20-40% active ingredient for liquid handling.
Sodium Formaldehyde Sulfoxylate
Sodium formaldehyde sulfoxylate (NaHSO2·CH2O) is a sulfoxylate reducing agent used in polymerizations and dye discharge printing. Classified in HTS 2831.90.00.00 as 'other' sulfoxylates when meeting inorganic compound criteria despite formaldehyde association. Technical grade powder or dihydrate form common.