Chemical · Product Detail
Sodium Metabisulfite
Reducing agent for dechlorination, chemical processing and qualified food or photographic applications.
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Sodium Metabisulfite at a Glance
ZXCHEM is a sodium metabisulfite supplier and exporter in China, CAS 7681-57-4. It is a reducing agent for dechlorination, chemical processing and food or photographic applications. It is supplied as white crystalline powder; available grade: Technical ≥96.5%; food ≥97%; photo ≥98%.
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Standard lead time is approximately 14 days from order confirmation.
Sodium Metabisulfite Specifications
Each row applies only to its named grade. Sulfur dioxide and trace-metal limits are not interchangeable between grades. No universal food-market certification is implied.
Commercial Information
Product Series
Technical grade
Assay ≥96.5%; iron ≤0.005%.
Food grade
Assay ≥97%; iron ≤0.002%; lead ≤0.0005%.
Photographic grade
Assay ≥98%; heavy metals ≤5 ppm; selenium ≤1 ppm.
Storage & Shipping
Storage Conditions
Keep tightly closed in a cool, dry, ventilated place. Protect against moisture and contamination; keep away from incompatible materials. Avoid acids and strong oxidizers.
Packaging integrity
Inspect the closure and liner before receipt. Keep the original label and reseal opened containers to prevent contamination.
Packaging
Technical and food grades: 25 kg lined woven bags or 1,250 kg bulk bags. Photographic grade: 25 kg, 50 kg or 1,000 kg bags; confirm format.
Handling & Protection
Review the grade SDS before transfer, sampling or processing. Use suitable ventilation, protective equipment and compatible handling equipment.
What Is Sodium Metabisulfite?
Sodium metabisulfite (Na2S2O5), CAS 7681-57-4, dissolves in water to form bisulfite and works as a reducing agent and preservative. Typical uses are dechlorination in water treatment, reduction and bleaching in textile and chemical processing, food preservation and photographic processing.
Three grades are available, each with its own assay and impurity limits: technical ≥96.5%, food ≥97% and photographic ≥98%. Please state the grade in your inquiry. Food use needs the food-grade documents and approval in the destination market.
Acid contact, heat and moisture release sulfur dioxide, so dissolve and transfer the product with good ventilation. It is not regulated as dangerous goods under DOT, IMDG or IATA.
As a sodium metabisulfite supplier and exporter in China, ZXCHEM packs technical and food grades in 25 kg lined woven bags or 1,250 kg bulk bags, and the photographic grade in 25 kg, 50 kg or 1,000 kg bags. Lead time is about 14 days from order confirmation.
See all water treatment chemicals in our catalog.
Sodium Metabisulfite Applications
Dechlorination
Removes residual chlorine from process water, wastewater and membrane feed water. The dose follows the chlorine level, with contact time and residual sulfite monitored.
Textile and chemical processing
Reducing and bleaching agent in textile and chemical processes. Equipment must be compatible with bisulfite solutions, and sulfur dioxide exposure is controlled.
Food and photographic uses
The food grade is used for permitted preservation uses and the photographic grade for developer and fixer baths. Each grade comes with its own documents.
Why Source Sodium Metabisulfite from ZXCHEM
Combined chemical orders
Source several chemical raw materials through one ZXCHEM contact. We coordinate product selection, quotations and suitable consolidated shipments so you can plan the order with one team.
Dedicated R&D Laboratory
Discuss specifications, sample results and application questions with our technical team. Our dedicated R&D laboratory supports product testing and helps clarify material selection.
Experienced Chemical Logistics
ZXCHEM has more than 30 years of experience in dangerous-goods transportation. We coordinate suitable shipments through logistics companies in which we hold equity interests in Qingdao, Shanghai, Guangzhou and Tianjin.
Dedicated Purchasing Support
Your account manager follows the order from quotation and contract signing through shipment and after-sales support. One contact coordinates technical documents, commercial details and delivery updates.
Sodium Metabisulfite FAQ
What grade of Sodium Metabisulfite is listed?
The listed grade is Technical ≥96.5%; food ≥97%; photo ≥98%, supplied as white crystalline powder. The grade comparison and TDS distinguish the separate limits; specify the required grade on your inquiry.
Can I request an evaluation sample of Sodium Metabisulfite?
Yes. Send the application, target grade and test quantity, and we confirm the sample and technical documents. Read the SDS before handling or laboratory evaluation.
How is Sodium Metabisulfite packed and stored?
Technical and food grades: 25 kg lined woven bags or 1,250 kg bulk bags. Photographic grade: 25 kg, 50 kg or 1,000 kg bags; confirm format. Keep tightly closed in a cool, dry, ventilated place. Protect against moisture and contamination; keep away from incompatible materials. Avoid acids and strong oxidizers. Confirm the packing selected for the quotation and destination before placing the order.
Which documents are available for Sodium Metabisulfite?
Download the TDS for the listed technical grade and the reference SDS for safety and transport information. Each order comes with a batch COA; include any market or end-use requirements in your inquiry.
Request a Quote for Sodium Metabisulfite
Tell us the required grade, quantity, destination port and documents. We reply within one business day.
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