Click on a catalog number in the tables below for more information or to purchase a test kit.
Range | MDL | Method | Kit Catalog No. | Refill Catalog No. |
---|---|---|---|---|
2-20 ppm as SO3 | 2.0 ppm | Iodometric | K-9602 | |
5-50 ppm as SO3 | 5.0 ppm | Iodometric | K-9605 | |
10-100 ppm as SO3 | 10 ppm | Iodometric | K-9610 | |
50-500 ppm as SO3 | 50 ppm | Iodometric | K-9650 | |
10-100 ppm as SO2 | 10 ppm | Ripper (Sulfite in Wine) | K-9610W |
Methods
Sulfite is not usually present in surface waters. If sulfite is discharged in effluents or from domestic wastewaters, it readily oxidizes to form sulfate. Sodium sulfite is the most common form of sulfite and is an excellent reducing agent with applications as an oxygen scavenger. Sulfite concentrations in boiler and process waters must be monitored routinely to avoid overtreatment. Waste treatment plants that use sulfur dioxide to remove excess chlorine must monitor their effluents for sulfite.
Sulfites have been used for centuries to sanitize and preserve foods. They are used worldwide in the wine industry as antioxidant and antimicrobial agents. However, sulfites have been identified as causative agents in certain allergic reactions suffered by asthmatics. As a result, the FDA and the Bureau of Alcohol, Tobacco, and Firearms have mandated that sulfites in foods and beverages, at levels of 10 ppm or higher, be identified on the label.
CHEMetrics free sulfite kits can be used to measure thiosulfate. Multiply test results by 1.4 to convert from ppm sulfite (SO3) to ppm thiosulfate (S2O3). The sulfite kits cannot distinguish between thiosulfate and sulfite.