Decolorization of Indigo Carmine Solution using Discharge on Surface of a Gas-layer in Water

Abstract

A new method of a water treatment utilizing radicals produced by the discharge on the surface of a gas-layer in water is proposed. Radicals with short lifetime (e.g. OH radical and atomic oxygen) are used effectively for the water purification because radicals contact with water directly. The gas-layer (like a bubble) is formed when the gas is supplied to the reactor. The supply gas was argon. The indigo carmine solution was decolorized using the discharge on the surface of a gas-layer in water. The energy consumption of 1-pulse evaluated from waveforms of the applied voltage and the circuit current. When the total energy consumption was 5.46Wh, the decolorization rate of the indigo solution was 98.0%. The TOC concentration of the indigo solution which performed the discharge process was measured. When the charging voltage was 48.8kV, the treatment efficiency of TOC was 0.174g/kWh.