Description

Sodium Metabisulfite is an inorganic salt widely recognized for its potent reducing and antioxidant properties. This compound is essential for controlling oxidation, preserving freshness, and acting as a bleaching agent across numerous industrial processes. Key industries that rely on this versatile chemical include food and beverage production, water treatment, pharmaceutical manufacturing, and textile processing. Its effectiveness and cost-efficiency make it a staple in formulations requiring reliable sulfur dioxide release.

Application

• Food & Beverage Preservation: Used as an antioxidant and preservative (E223) in wines, beers, dried fruits, and fruit juices to prevent spoilage and browning.
• Water Treatment: Acts as a dechlorinating agent and oxygen scavenger in municipal water systems and industrial boiler feed water.
• Pharmaceuticals: Serves as an antioxidant in certain drug formulations and as a sterilizing agent in equipment cleaning.
• Textile & Leather Processing: Employed as a bleaching and dechlorinating agent for wool, cotton, and leather.
• Photography: Used in developing solutions as a reducing agent.
• Chemical Synthesis: Functions as a sulfonating and reducing agent in various organic synthesis reactions.
• Mining & Metallurgy: Utilized in gold extraction processes (cyanide detoxification) and mineral flotation.
• Pulp & Paper Industry: Applied in bleaching processes for chemical pulps.

Basic Information

Product Name	Sodium Metabisulfite
CAS No.	7757-74-6
Molecular Formula	Na2S2O5
Molecular Weight	190.11 g/mol
Synonyms	Sodium Pyrosulfite; Disodium Disulfite; Disodium Metabisulfite; Sodium Disulfite; Anhydrous Sodium Metabisulfite; E223; SMB
EINECS	231-673-0

Quality Control

Our Sodium Metabisulfite is manufactured under strict quality management systems. We offer various grades, including Food Grade (FCC), Technical Grade, and Photo Grade, each meeting stringent purity and consistency requirements. Every batch is tested against relevant specifications, and a comprehensive Certificate of Analysis (COA) is provided to ensure traceability and compliance with customer and regulatory standards such as FCC, USP, and REACH.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area away from heat sources and incompatible materials. This product is light-sensitive (store away from light) and easily oxidized (store under inert atmosphere). Keep container tightly sealed when not in use to minimize moisture absorption and oxidation. Recommended storage temperature is 15-25°C.

Specification

Item	Specification
Appearance	White or yellowish crystalline powder
Identification (IR)	Conforms
Assay (as Na2S2O5)	≥ 97.0%
SO2 Content	≥ 64.0%
Iron (Fe)	≤ 10 ppm
Heavy Metals (as Pb)	≤ 5 ppm
Water Insolubles	≤ 0.05%
pH (5% Solution)	4.0 - 5.0

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.