Improving Water Quality

WE ARE WRITING to correct a possible misconception that may result from a statement made in the article "Inherently Safer Water Purification" (C&EN, Feb. 9, page 22). The article states that one type of on-site generator manufactured by MIOX "produces a mixed oxidant solution of 0.4% sodium hypochlorite and other oxidants such as ozone and hydrogen peroxide." The correct statement is "the mixed oxidant solution contains 0.4% free available chlorine but behaves chemically and biocidally as though it contained other stronger oxidants in addition to measureable FAC."

Although it is possible that ozone and hydrogen peroxide are generated at the anode, they have not been detected in peer-reviewed third-party research. MIOX does not officially claim these chemicals as the constituents. Instead, we prefer to direct customers to published third-party comparative studies and applications where the mixed-oxidant chemistry benefit is clear. These include applications where lower disinfection by-product formation is needed to reach compliance with drinking water regulations, sites where superior microorganism inactivation performance compared to hypochlorite is needed, and applications where the removal of biofilm and biofilm/scale combinations can significantly improve water quality.

Carlos Perea, Justin Sanchez, Wesley Bradford, and Susan B. Rivera MIOX Corp.
Albuquerque, N.M.