Product Overview & China Production Capacity
Colloidal Silicon Dioxide (Fumed Silica, CAS 7631-86-9, molecular formula SiO₂) is a submicron-sized, amorphous, high-surface-area silicon dioxide produced by vapor-phase hydrolysis. In pharmaceutical applications, it functions as a glidant (improving powder flow at 0.1–0.5% concentrations), anti-caking agent, adsorbent for liquid actives, tablet disintegrant aid, and viscosity modifier in semisolid preparations. It is one of the most essential functional excipients in solid dosage manufacturing.
China is a major global producer of fumed silica with annual capacity exceeding 200,000 MT. Our production facility in Jiangxi Province operates four dedicated fumed silica reactors with 25,000 MT/year combined capacity, producing hydrophilic grades from 130 to 380 m²/g specific surface area to cover all pharmaceutical glidant and adsorbent applications.
Manufacturing Standards & Quality Assurance
Production is quality-certified with ISO 9001:2015 quality management. The product meets USP/NF (Colloidal Silicon Dioxide), EP (Colloidal Anhydrous Silica), and ChP monograph specifications. Our flame hydrolysis process uses high-purity silicon tetrachloride feedstock to produce consistently pure amorphous silica with controlled primary particle size and surface area.
Quality control includes BET specific surface area measurement, pH determination, loss on drying, loss on ignition (SiO₂ assay), sieve residue, tamped density, chloride content, heavy metals, and microbial limits. TEM imaging is used for primary particle size verification. Each batch is tested against the full pharmacopeial specification panel.
Technical Specifications
| Parameter | Specification |
|---|---|
| Appearance | Light, white, amorphous powder |
| SiO₂ Content (ignited basis) | ≥99.0% |
| Specific Surface Area (BET) | 130–380 m²/g (grade dependent) |
| Loss on Drying (105°C, 2h) | ≤2.5% |
| Loss on Ignition (1000°C) | ≤5.0% |
| pH (4% suspension) | 3.5–5.5 |
| Tamped Density | 40–100 g/L (grade dependent) |
| Sieve Residue (45 µm) | ≤0.05% |
| Heavy Metals (as Pb) | ≤10 ppm |
| Chloride | ≤0.025% |
Packaging & Export Logistics
Supplied in 10 kg multi-wall paper bags with PE liner (standard pharmaceutical packaging) or 5 kg bags for smaller users. Due to low bulk density, container loading is approximately 3–5 MT per 20′ FCL. Store in a dry environment at room temperature in tightly sealed containers to prevent moisture absorption. Shelf life is 48 months from manufacture.
We ship from Shanghai and Shenzhen ports. Given the low bulk density, we offer compressed-packaging options that improve container utilization by up to 40%. Full documentation includes COA, MSDS, and regulatory support letters.
China Supply Advantage
Chinese-manufactured pharmaceutical-grade colloidal silicon dioxide offers 40–55% cost savings compared to leading Western brands while meeting identical pharmacopeial specifications. Our large-scale flame hydrolysis production achieves economies of scale that major Western producers cannot match at equivalent quality levels.
MOQ is 200 kg with production lead time of 7–10 business days. We offer the full range of pharmaceutical-relevant grades including 200 m²/g (standard glidant grade) and 300 m²/g (high adsorbency grade). Technical support includes angle of repose testing and flow improvement optimization studies. Contact us for grade recommendations and pricing.