Sulfur dioxide
Description
Sulfur dioxide (CAS 7446-09-5), commonly referenced as SO2 or E220, is an inorganic gas used across food processing, industrial manufacturing, and water treatment. It serves as a preservative, antioxidant, and reducing agent.
Its dual role in microbial control and oxidation prevention makes it a procurement staple across multiple regulated industries. In food and beverage production, SO2 is applied to wines, dried fruits, and fruit juices.
This chemical is essential to inhibit microbial growth and prevent browning during storage and processing. Pulp and paper manufacturers use it to bleach cellulose fibers and neutralize excess chlorine in effluent streams.
In mining and hydrometallurgy, sulfur dioxide reduces hexavalent chromium and precipitates metals from process liquors during ore refining. Water treatment facilities apply it for dechlorination of potable and wastewater streams.
Sulfur dioxide is supplied as a liquefied gas in pressurized cylinders and ISO tank containers. Bulk tonnage is available for high-volume industrial users requiring consistent supply chains for large-scale operations.
Food-grade material meeting E220 specifications is available for regulated applications in the food and beverage sector. Technical-grade supply is standard for pulp, paper, mining, and water treatment end uses.
Physical Properties
| Melting Point | -75.5 °C |
| Boiling Point | -10.05 °C |
| Density | 2.811 x 10<sup>-3</sup> g/cm³ |
| Appearance | Sulfur dioxide is a noncombustible colorless gas at ambient temperatures with a characteristic, strong, suffocating odor. The Odor Threshold is 1.1ppm. Shipped as a liquefied compressed gas. |
| Color | colorless |
| Odor | Pungent odor detectable at 0.3 to 5 ppm |
| Form | colorless gas |
| Water Solubility | %H2O: 17.7 (0°C), 11.9 (15°C), 8.5 (25°C), 6.4 (35°C); % other solvents: 25, alcohol; 32, methanol [MER06] |
| Vapor Pressure | 1779 mm Hg ( 21 °C) |
Safety & Handling (Learn More)
Trade & Regulatory
| UN Number | 2037 |
| ADR Class | 2.3 |
| Storage Class | 2A - Gases |
| WGK (Germany) | 1 |
Documentation
Other Names
Sulphur dioxide , sulfur dioxide|sulphur dioxide|sulfurous oxide|sulfurous anhydride|sulfurous acid anhydride|sulfur oxide|R-764|SO2|E220
Related Products
Need a chemical? Get a quote within 24 hours.