Kinetics of decolorization of azo dye by bipolar pulsed barrier discharge in a three-phase discharge plasma reactor

Degradation of Azo Dye Acid Red 88 by Gas Phase Dielectric Barrier Discharges

“…However, when the input power was set beyond 60 W the amount of OH • radical generated began to decrease and became undetectable at the input power of 127 W. The input power has a significant effect on active species production. As the input power increases, electrons gain more energy in the electric field and induce stronger ionization of oxygen and water molecules by collision [11]. The resultant increase of active species formation such as OH • radicals can be confirmed from Fig.…”

“…This finally determines the abundance of gas molecules broken down and the quantities of active species generated [18]. On the other hand, gas flow rate changes the residence time of the gas in the reactor and the reaction time of the gas-phase active species (such as OH • radical and O 3 ) with the pollutant molecules, therefore the utilization ratio of the active species will vary [11]. As the gas flow rate increases, more gas molecules will pass through the DBD reactor and break down by collision with energetic electrons within the same time span, and hence more reactive species can be generated.…”

“…Its attractive feature lies in the ability to generate highly reactive species such as OH • radicals. Most advanced oxidation technologies developed such as photocatalytic oxidation and pulsed electrical discharges focus on OH • radical production directly in the aqueous phase [9][10][11][12][13][14][15][16]. Gas-phase electrical discharge reactors such as dielectric barrier discharge (DBD) and pulsed corona discharge, on the other hand, have long been used to generate ozone (O 3 ), a relatively selective oxidant, with clean dry air or pure oxygen [17,18].…”

Effect of granular activated carbon on degradation of methyl orange when applied in combination with high-voltage pulse discharge

“…These techniques succeed in decolorizing effluents and lowering dye concentration to the ppm level, but fail to achieve a high degree of mineralization to CO 2 [2]. In recent years there has been growing interest in the development of nonthermal plasma methods for the degradation of colored wastewater containing organic dyes [3][4][5][6][7][8][9][10]. The nonthermal plasma produced by pulsed discharge can generate various reactive chemical species in water, such as radicals (H · , O · , OH · ) and molecular species (H 2 O 2 , H 2 , O 3 ) [11].…”

Influence of non-thermal plasma pre-treatment on the scaling characteristics of viscous oil wastewater during evaporation

“…Plasma treatment appears to be a promising alternative for the oxidation of aqueous organic pollutants [12]. The pulsed high-voltage direct current (DC) discharge reactor generates NTP through narrow pulsed corona discharges.…”