Which oxygen scavenger is commonly used in industrial corrosion treatment?

Sodium sulfite is widely recognized as an effective oxygen scavenger in various industrial applications, particularly in systems tasked with controlling corrosion. When added to water, sodium sulfite reacts with dissolved oxygen, thereby significantly reducing the oxygen content in the system. This is crucial in preventing corrosion, especially in boilers and cooling water systems, where oxygen can lead to pitting and other forms of damage to metal surfaces.

The mechanism of sodium sulfite involves the formation of sodium sulfate upon reaction with oxygen, which helps to avoid the oxidation of metals typically associated with oxygen presence. By ensuring that oxygen levels are kept low, sodium sulfite effectively protects the integrity and longevity of the equipment used in industrial processes.

In contrast, the other substances mentioned serve different purposes. Chlorine is primarily used as a disinfectant and does not function effectively as an oxygen scavenger. Calcium carbonate acts as a scale inhibitor and does not significantly impact oxygen levels. Polyphosphate is often used to sequester hardness ions to prevent scale formation but does not serve as an oxygen scavenger either.