Inactivation of bacteria by solids coated with magnesium peroxide

Abstract

Heating diatomaceous earth or sand that has been soaked with a solution of magnesium chloride results in coating of the materials with magnesium oxide. The addition of hydrogen peroxide converts this coating to magnesium peroxide. The magnesium peroxide coating on sand or diatomaceous earth is relatively stable during storage. Greater than 50% of the oxidizing power remained after 6 months storage at room temperature. The addition of diatomaceous earth or sand coated with magnesium peroxide to aqueous solutions led to release of hydrogen peroxide into the solution, reduced the number of bacteria, and prevented bacterial growth as compared with controls. Filters made with modified and untreated diatomaceous earth removed bacteria from water equally well. However, bacteria survived or grew on filters made with untreated materials, but were greatly reduced in numbers on filters made with modified diatomaceous earth.

Key words:

• Diatomaceous Earth
• Hydrogen Peroxide
• Magnesium Peroxide
• Microporous Filters
• Inactivation
• Bacteria

Notes

Journal paper N‐00713 from the Florida Agricultural Experiment Station, Gainesville, FL 32611.