What chemical is commonly used for dechlorination?

Sulfur dioxide is commonly used for dechlorination because it effectively removes chlorine from water. It acts as a reducing agent, reacting with chlorine to form chloride ions, thus neutralizing its disinfecting properties. This process is essential in water treatment to prevent harmful effects on aquatic life and ensure that water is safe for consumption and recreational activities after chlorination processes.

Sodium chloride, although it is linked to chlorine due to its structure, does not serve the purpose of removing chlorine from water. Chlorine itself is a disinfectant and would not be used for dechlorination. Potassium iodide, while it has applications in medical treatments and certain analytical procedures, is not used for dechlorination in water treatment processes. This distinction is critical in understanding water treatment options for ensuring compliance with safety standards.