Chemical and Physical Characteristics of Pulsed Electrical Discharge Within Gas Bubbles in Aqueous Solutions

Abstract

The chemical and physical characteristics of pulsed electrical discharge within gas bubbles immersed in an aqueous solution were investigated using a reactor with long protrusion length high voltage needle electrodes. Argon gas was introduced at the base of the needle electrode causing gas bubbles to flow upwards in contact with the needle. The effects of needle protrusion length were evaluated by using 2, 4, and 6 cm length needles under a wide range of power input (3-78 W). No significant differences in chemical or electrical characteristics were found among the different protrusion lengths. H 2 and H 2 O 2 generation rates were proportional to input power and the energy yield efficiency for these species was not affected dramatically by input power. The results of discharge within bubbles in aqueous solution were also compared with those for direct liquid phase discharge and gas phase discharge above the liquid surface.

A kinetic model for H2 production by plasmolysis of water vapours at atmospheric pressure in a dielectric barrier discharge microchannel reactor

“…This is because the increased availability of H and HO 2 to participate in Reaction (23) to form H 2 and O 2 . Reaction (14) was found to be a key step in forming H 2 O 2 by recombination of OHeOH [47]. By deselecting Reaction (14) from the scheme, the concentration of H 2 O 2 was dropped to 10 À3 moles/m 3 from 10 À1 moles/m 3 .…”

Analysis of Electrical Discharge Plasma in a Gas‐Liquid Flow Reactor Using Optical Emission Spectroscopy and the Formation of Hydrogen Peroxide

“…Gas–liquid (water) discharges are of great interest to efficiently produce hydroxyl radicals, • OH, that in turn form hydrogen peroxide, H 2 O 2 , or that oxidize many organic compounds . A variety of means to contact plasma with liquid water have been investigated including cases where the plasma propagates along the interface of a gas–liquid system . In one example a gas–liquid pulsed corona discharge is formed where the cathode is immersed in the liquid phase and the ground electrode is placed in the surrounding gas phase .…”

Decomposition of Acetic Acid Using Multiple Bubble Jets with Pulsed Electrical Discharge

“…Figure 7 shows the dissolved H 2 O 2 concentration in a CH 3 COOH solution and pure water with applied frequency after the treatment. The experimental conditions were as [5,13].…”

“…This is because the oxidation potential of O and OH radicals is higher than that of O 3 at atmospheric pressure, although the lifetime of O and OH radicals is shorter than that of O 3 in water. Therefore, it is very important to clarify all the physicochemical correlations among bubble dynamics, discharge characteristics, and decomposition characteristics to achieve the highest energy efficiency [5][6][7].…”