Industrial, Pharmaceutical & Photographic Grade Anhydrous Sodium Thiosulfate (Na2S2O3) CAS 7772-98-7 for Water Treatment, Photography, Paper Bleaching

Anhydrous Sodium Thiosulfate (CAS:7772-98-7,EINECS:231-867-5, HS Code:28323000) is a white crystalline inorganic powder. It is produced by concentration, crystallization and dehydration of sodium thiosulfate solution. We supply industrial, pharmaceutical and photographic grades that comply with national standards, pharmacopoeia and international industrial specifications. The product dissolves easily in water and slightly soluble in ethanol, featuring stable chemical properties and excellent reducing capacity. It is widely applied as functional reagent in water treatment, photography, paper bleaching and medical fields.

Applications
Water Treatment
It acts as efficient dechlorinating agent to eliminate residual chlorine in tap water, circulating water and wastewater. It also functions as reducing agent to treat heavy metal pollutants in industrial effluents, achieving qualified discharge of wastewater.
Photographic Industry
Serves as core fixing agent for traditional film and photo paper. It can dissolve unexposed silver halide on photosensitive materials, stabilize image tone and extend storage life of photographs, which is an essential material for photographic processing.
Paper Bleaching Industry
Used as mild reducing bleaching agent for pulp and paper products. It improves paper whiteness without damaging plant fibers, and also works as auxiliary agent for deinking of recycled paper in papermaking process.
Pharmaceutical & Other Applications
In medical field, it is prepared into medicaments for detoxification against cyanide and heavy metal poisoning, and used as skin cleaning and disinfecting agent. Besides, it is widely used as analytical reagent and chemical intermediate in laboratory and fine chemical production.

Product Advantages
✅ Complete grade selection: Three grades available for industrial, pharmaceutical and photographic scenarios
✅ Low impurities: Strict quality control meets high requirements of medical and photographic industries
✅ Good solubility: Dissolves rapidly in water, convenient for preparation and on-site use
✅ Stable performance: Maintains effective reducing and fixing ability during long-term storage
✅ Multi-functional: Integrates dechlorination, bleaching, fixing and detoxification functions
✅ Full supporting documents: Complete COA and qualification certificates for export trade

Packaging & Storage
Standard packaging: 25kg woven bags with inner PE liner; 1000kg FIBC bulk bags for bulk orders. Pharmaceutical and photographic grades adopt sealed fiber drums for better protection. The product is slightly hygroscopic. Store in a cool, dry and well-ventilated warehouse. Keep containers tightly sealed, and keep away from strong acids, oxidants and toxic substances. The shelf life is 24 months under proper storage conditions.
Safety Information
Classified as non-hazardous goods for regular transportation. Fine powder may cause mild irritation to respiratory tract, eyes and skin. Wear dust mask and protective gloves during handling. In case of contact with skin or eyes, rinse immediately with plenty of clean water. Complete MSDS and relevant qualification certificates can be provided upon request.

1. 1.A 70,000 ㎡ warehouse (20,000 MT capacity) with moisture-proof and temperature-controlled systems, enabling efficient fulfillment of large-volume orders.
2. 2.Free samples (Ship within 3-7 days) to let you test products at zero trial cost.
3. 3.Transparent lead time for hazardous chemicals: 45–60 days, with clear delivery schedules.
4. 4.Certified with a Hazardous Chemical Business License and ISO certification, ensuring smooth customs clearance.
5. 5.6 packaging options with customizable logos to minimize product loss during transportation.
6. 6.Over 400 chemical SKUs available for one-stop procurement, helping you reduce sourcing costs.