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This study examined processes of decomposing phenol and its derivatives (resorcin, pyrocatechol and hydroquinone) in aqueous solutions under the action of an atmospheric pressure oxygen dielectric barrier discharge in the presence or absence of catalysts in the plasma zone. Two types of catalysts were tested, NiO and TiO 2 . It was found that both materials exhibited catalytic properties. The action of NiO accelerated the step of phenol destruction while the action of TiO 2 catalyst resulted in a more preferable composition of decomposition products and provided a higher degree of carboxylic acid conversion into carbon dioxide than the NiO catalyst.

Section: Introductionmentioning

confidence: 99%

Comparative Actions of NiO and TiO2 Catalysts on the Destruction of Phenol and its Derivatives in a Dielectric Barrier Discharge

Bubnov

Burova

Grinevich

et al. 2007

“…The main advantages of this apparatus are: an increase of the gas-liquid boundary surface area exposed to active species (free electrons, ions and radicals), an enhancement of the concentration of the pollutants and of electric field near the droplet surface, and a production of hydrated electrons. (14,15) This paper presents experimental results on the degradation of aqueous phenol solution in the presence of the gliding arc plasma. The role of the supply voltage, the electrode gap distance, and the chemical and physical bi-phase flow properties are investigated.…”

Section: Introductionmentioning

confidence: 99%

Degradation of Phenol in Aqueous Solutions by Gas–Liquid Gliding Arc Discharges

Yan

et al. 2006

The efficiency of a gliding arc reactor designed with the aim to degrade aqueous phenol solutions is studied as a function of supply voltage, electrode gap distance, and gas-liquid flow properties. This efficiency, which steeply increases when increasing the supply voltage, can reach 96% when the minimum electrode distance is fixed at 3 mm. Experiments show that phenol degradation efficiency also depends on solution pH, Fe 2+ addition, gas nature and gas flow rate. Furthermore, degradation pathways of phenol in aqueous solutions are proposed.

“…(5−8) These processes induce the change of valence electrons in metal ions such as Fe 2+ → Fe 3+ , Ce 3+ → Ce 4+ , Tl + → Tl 3+ (6) resulting in the discoloration of the watersoluble dyes. (7) The studies of the gas phase were mainly stimulated by the opportunity to measure the irradiation spectrum of metal-containing compounds dissolved in the liquid phase through the optical emission spectroscopy (OES). The reason is that the plasma-electrolyte system allows easy transfer of the solute into gas phase due to the cathode sputtering phenomena of liquid cathode.…”

Section: Introductionmentioning

confidence: 99%

“…The E/N parameter is an analogue of temperature in the description of the electron kinetics under non-equilibrium plasma conditions. Among the parameters mentioned above, the order of magnitude for E/N is known, (7) while N can be calculated (P=N kT). Unfortunately, systematic experimental data on the gas temperature as well as on the gas phase composition are absent.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of Atmospheric Pressure Air Glow Discharge with Aqueous Electrolyte Cathode

Титов

Рыбкин

Maximov

et al. 2005

We investigated the characteristics of atmospheric pressure (AP) air glow discharge with aqueous electrolyte cathode. Distilled water or aqueous solutions of HNO 3 , KCl, KBr and KI were utilized as a cathode. The cathode voltage drop, electric field strength, gas temperature as well as emission intensity of some lines of OI, H, K, Na and bands of N 2 , OH, NO were measured at discharge current from 10 to 50 mA. The procedure of gas temperature measurement on the base of non-resolved structure of N 2 (C 3 u → B 3 g ) bands was described. The reduced electric field strength (E/N) was obtained, which showed that the discharge existed in the normal mode. On the base of these data, the regularities of optical emission were discussed.KEY WORDS: Atmospheric pressure plasma with aqueous electrolyte cathode; emission spectrometry; gas temperature.