Description

Potassium Metabisulfite is a versatile inorganic salt widely recognized for its potent antioxidant and preservative properties. Its primary value lies in its ability to release sulfur dioxide, which effectively inhibits microbial growth and prevents oxidation, thereby extending the shelf life of various products. This makes it an essential chemical for industries such as food and beverage, water treatment, pharmaceuticals, and photography.

Application

• Food & Beverage Preservation: Used as a preservative (E224) and antioxidant in wines, beers, fruit juices, dried fruits, and vegetable products to prevent browning and spoilage.
• Water Treatment: Acts as a dechlorinating agent and oxygen scavenger in municipal and industrial water systems, including boiler feed water.
• Pharmaceutical Manufacturing: Serves as an antioxidant in certain drug formulations and as a sterilizing agent for equipment.
• Photographic Industry: Employed as a reducing agent in photographic developers and fixers.
• Textile & Leather Processing: Used in bleaching and dechlorination processes for textiles and as a reducing agent in leather tanning.
• Chemical Synthesis: Functions as a sulfonating or reducing agent in various organic synthesis reactions.
• Mining & Metallurgy: Applied in gold extraction processes (cyanide detoxification) and as a flotation agent.

Basic Information

Product Name	Potassium Metabisulfite
CAS No.	4429-42-9
Molecular Formula	K2S2O5
Molecular Weight	222.32 g/mol
Synonyms	Potassium Pyrosulfite; Dipotassium Disulfite; Dipotassium Metabisulfite; Potassium Disulfite; E224; UN 2290; Sulfurous Acid, Dipotassium Salt
EINECS	224-677-3

Quality Control

Our Potassium Metabisulfite is manufactured under a strict quality management system. We offer grades compliant with FCC (Food Chemicals Codex) for food applications and can supply material meeting relevant pharmacopeial standards (e.g., USP/EP) for pharmaceutical use. Every batch undergoes rigorous analytical testing to ensure consistent purity and performance. Certificates of Analysis (COA) are available upon request.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area away from moisture (hygroscopic), heat, and incompatible materials such as strong acids and strong oxidizers. Keep container tightly sealed when not in use to minimize exposure to air.

Specification

Item	Specification
Appearance	White crystalline or granular powder
Identification (IR)	Conforms
Assay (as K2S2O5)	≥ 96.0 %
SO2 Content	≥ 57.0 %
Iron (Fe)	≤ 10 ppm
Heavy Metals (as Pb)	≤ 10 ppm
Water Insoluble Matter	≤ 0.05 %
pH (1% Solution)	3.5 - 4.5

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