Study On Onset And Reactive Activity Of Glow Discharge Plasma

Glow discharge plasma (GDP) is a novel advanced oxidation technology, since many species such as OH, H, H2O2are produced in the discharge process. These radicals can diffuse in the surrounding liquid and be used for the removal of dissolved compounds. Especially, OH, with higher oxidation potential, can break the molecular bonds of organic pollutants. This makes GDP particularly suitable for decontamination. In addition, GDP has many advantages, such as simpler equipment, lower applied voltage and higher energy efficiency. In order to study the onset and active species of GDP, this paper investigated Ⅰ-Ⅴ characteristic curve, concentration of H2O2and discoloration efficiency of Acid Orange (AO) with three kinds of glow discharge reactors.This paper systematically investigated the onset multi-anode contact glow discharge electrolysis (m-CGDE). It was found that the critical voltage of m-CGDE was same to that of single anode. The concentration of H2O2in the anolyte and discoloration rates of AO increased with the increase of treatment time and anode number. It was also demonstrated that improved m-CGDE reactor efficiently accelerated the discoloration process of AO by replacing platinum wire with stainless steel wire. For higher concentration AO solution, m-CGDE also showed higher discoloration efficiency.In addition, this paper investigated the onset of underwater glow discharge. The experimental conditions such as the position of the anode, cathode material and size, voltage were optimized. The results showed that VD decreased with the increasing conductivity of solution. Different electrolytes had insignificant effect on VD. It was found that the critical voltage of multi-anode glow discharge electrolysis (m-GDE) was same to that of single anode. The concentration of H2O2in the anolyte and discoloration rates of AO increased with the increase of treatment time and anode number. For higher concentration AO solution, m-GDE also showed higher discoloration efficiency. COD and TOC removal rate increased with an increase of anode number.Finally, this paper investigated the onset and active activity of diaphragm glow discharge (DGD). It was found that Ⅰ-Ⅴ characteristic was similar to that of CGDE. IThe concentration of H2O2in the anolyte and discoloration rates of AO increased with the increase of hole’s diameter. The discoloration rates of AO increased with the increase of the concentration of H2O2in the same electrolyte. Different electrolytes had effect on the concentration of H2O2in the anolyte and discoloration rates of AO, especially the NaCl solution.