In wastewater treatment, what is the most common application of the chemical reduction process?

The most common application of the chemical reduction process in wastewater treatment is converting hexavalent chromium to trivalent chromium. This transformation is significant because hexavalent chromium is highly toxic and carcinogenic, posing considerable risks to human health and the environment. The reduction process effectively changes the hexavalent form, which is more soluble and mobile in water, into trivalent chromium, which is significantly less toxic and can be more readily removed from water.

This chemical reduction often involves the use of reducing agents that donate electrons to the chromium species, thereby facilitating this conversion. As a result, the trivalent form can undergo precipitation and can be captured through conventional treatment methods, making it safer for discharge into the environment or for further processing in treatment facilities.