Product Overview & China Production Capacity
Zinc Sulfate (ZnSO₄, CAS 7733-02-0, MW 161.47 anhydrous / 287.56 heptahydrate) is an essential mineral supplement used in pharmaceutical zinc preparations, ophthalmic solutions, and nutritional products. China is the world’s largest zinc producer, and this upstream advantage supports massive zinc sulfate production capacity exceeding 500,000 metric tons annually from facilities in Hunan, Yunnan, Guangxi, and Henan provinces. Both monohydrate and heptahydrate forms are available in pharma, feed, and fertilizer grades at competitive pricing.
In pharmaceutical applications, zinc sulfate serves as the active ingredient in zinc supplement tablets and syrups for treatment and prevention of zinc deficiency, a component in oral rehydration solutions (ORS), and an ingredient in ophthalmic astringent preparations. The heptahydrate form (ZnSO₄·7H₂O) is most commonly specified in pharmacopoeial monographs. Chinese manufacturers produce high-purity zinc sulfate through dissolution of zinc oxide or zinc metal in sulfuric acid followed by crystallization and recrystallization.
Manufacturing Standards & Quality Assurance
Production facilities maintain ISO 9001:2015, and FAMI-QS certifications. Quality testing includes assay (complexometric titration), pH, chloride, iron, lead, cadmium, arsenic, mercury, alkalies and alkaline earths, and microbial limits. Products comply with USP/NF, EP, BP, FCC, and ChP monograph specifications. Pre-market clearance documentation for nutritional supplement applications is available.
High-purity zinc oxide feedstock is dissolved in dilute sulfuric acid under controlled conditions. The resulting solution undergoes multiple purification steps including cementation (zinc dust addition to remove heavy metal impurities), activated carbon treatment, and filtration. Crystallization produces the heptahydrate form, which can be further dehydrated to monohydrate under controlled conditions. Each batch undergoes complete heavy metals analysis by ICP-MS to ensure pharmaceutical safety standards are met.
Technical Specifications
| Parameter | Specification |
|---|---|
| CAS Number | 7733-02-0 (anhydrous) |
| Molecular Formula | ZnSO₄·7H₂O (heptahydrate) |
| Molecular Weight | 287.56 g/mol (heptahydrate) |
| Appearance | Colorless transparent crystals or white powder |
| Assay (as ZnSO₄·7H₂O) | 99.0–104.0% |
| pH (5% aqueous) | 4.0–5.5 |
| Lead | ≤5 ppm |
| Cadmium | ≤3 ppm |
| Arsenic | ≤3 ppm |
| Pharmacopoeial Compliance | USP/NF, EP, BP, FCC, ChP |
Packaging & Export Logistics
Zinc sulfate is supplied in 25 kg or 50 kg PE-lined woven bags or fiber drums, palletized for container loading. Bulk 1,000 kg FIBCs are available. Lead time is 7–10 business days. FOB from Shanghai, Qingdao, or Tianjin; CIF and DDP terms supported.
Non-hazardous classification facilitates straightforward international shipping. Documentation includes CoA, SDS, and commercial shipping paperwork. Regulatory dossier support for supplement and pharmaceutical registration is available.
China Supply Advantage
China’s position as the world’s largest zinc metal producer provides unique feedstock cost advantages for zinc sulfate manufacturing, delivering pharma-grade material at 30–50% below Western producer pricing. Integrated zinc mining, smelting, and salt production operations ensure supply stability. Chinese zinc sulfate producers serve pharmaceutical, animal nutrition, and agricultural customers globally with consistent quality and responsive commercial support.