Fumed Silica (Aerosil)
Fumed silica, also known as pyrogenic silica, is an ultra-fine, non-porous silicon dioxide produced by flame hydrolysis of silicon tetrachloride. Classified under HTS 2811.22.5000 as 'other' silicon dioxide due to its synthetic chemical definition and high purity.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If pre-dispersed in paint or varnish media
When incorporated into polyamide formulations for coatings, it becomes a paint preparation under 3208.
If chemically prepared as anti-foaming agent
Silica-based defoamers are classified as prepared chemical additives, not pure compounds.
If in the form of silicon carbide rather than dioxide
Carbides of silicon are excluded and classified separately under 2849.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Provide production process documentation (flame hydrolysis) to distinguish from precipitated types and avoid 3824 mixtures
• Declare surface area (BET, typically 50-400 m²/g) and aggregate structure to support chemical compound status
Related Products under HTS 2811.22.50.00
Precipitated Silica Powder
Precipitated silica is a form of synthetic amorphous silicon dioxide produced by precipitation from a solution containing silicate salts. It falls under HTS 2811.22.5000 as 'other' silicon dioxide, distinct from natural diatomaceous earth or fused quartz, used primarily as a reinforcing filler in rubber and tire manufacturing.
Colloidal Silica Dispersion (50% Solids)
Colloidal silica is a stable suspension of amorphous silicon dioxide nanoparticles in water or solvent, used for chemical mechanical polishing in semiconductors. It qualifies under HTS 2811.22.5000 as silicon dioxide in a chemically defined colloidal form.
Synthetic Amorphous Silica Gel
Synthetic amorphous silica gel is a porous form of silicon dioxide manufactured by acidifying sodium silicate, used as a desiccant. It is classified in HTS 2811.22.5000 as 'other' silicon dioxide, meeting Chapter 28 chemical definition.
High-Purity Silica Powder for LEDs
High-purity synthetic silica powder (>99.99% SiO2) used in LED phosphor production and optical applications. Falls under HTS 2811.22.5000 as other silicon dioxide, chemically defined per Chapter 28 notes.
Nano-Silica Particles (20 nm)
Nano-sized amorphous silicon dioxide particles (average 20 nm) produced via sol-gel process for advanced composites. Classified as other silicon dioxide under HTS 2811.22.5000 due to its inorganic oxygen compound nature.