Silicotungstic Acid Hydrate from Japan
Silicotungstic acid hydrate (H4SiW12O40·xH2O) functions as a catalyst in esterification, under HTS 2841.80.00 for its tungstate core structure. Green acid catalyst.
Duty Rate — Japan → United States
5.5%
Rate breakdown
9903.05.860%Universal product exemption (U.S. note 52(b))
Import Tips
• Keggin structure verification via Raman spectroscopy
• Corrosive strong acid; UN 3260 proper shipping name
• Calcined vs hydrate forms distinguished by TGA