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

Abstract

The degradation of an azo dye, acid red 88 (AR88) in aqueous solutions by a gas-phase dielectric barrier discharge (DBD) system was investigated. The reactive species generated from the DBD system such as OH • radical, ozone and hydrogen peroxide were measured. The effects of various parameters such as gas flow rate, initial pH, input power, initial concentration of AR88 and the gas source on the degradation of AR88 were studied. The results show that OH • radical was the major reactive species generated when 100% relative humidity (RH) air was used. An aqueous solution of 25 mg L -1 AR88 was 96.3% degraded in 5 min treatment, and 68% of the initial total organic carbon was removed in 90 min treatment with 100% RH air at 60 W input power and 7 L min -1 gas flow rate. The degradation kinetics of AR88 followed a pseudo-first-order reaction and was dependent on the input power, gas flow rate, initial AR88 concentration and initial pH.

Degradation of pharmaceutical contaminant ibuprofen in aqueous solution by cylindrical wetted-wall corona discharge

“…However, the half-life time for 60 mg/l is almost 5 times of that for 10 mg/l, which means higher efficiency in case of the higher initial concentration. The behavior of the observed rate constant as a function of the initial concentration was consistent with Tang et al [34] for the degradation of azo dye acid red 88 by dielectric barrier discharge, as well as by Magureanu et al [22] and Gao et al [23].…”

Behavior of microorganisms in drinking water treatment by inductively coupled plasma system: Case study in ground water

“…The effect of frequency on removal efficiency operated at 20 mL/minute and operating time at 120 minute is displayed in Figure 3a The highest RE with respect to FC was similar to those obtained in previous studies [7,9,18,19]. However, the RE with respect to FC in the present study was higher than that achieved using floating media filter-microfiltration without and with coagulant [18], combination of MBR and chlorination [19], adsorption using a graphite adsorbent with electrochemical regeneration [8,12], and a membrane bioreactor [15]. The REs with respect to FC and TC were quite similar to those using pulsed high voltage [7] and were higher than those using RFICP in a batch experiment and …”

“…Previous studies found that active species are produced by plasma (O 3 , H 2 O 2 and  OH) by dissociation of oxygen and water molecules, which can dissolve into the solution and further degrade pollutants via oxidation processes [6,14,15,16]. In another study, the degradation of organic carbon and disinfection of pathogenic bacteria depended on UV light and shock waves produced by plasma discharges [15,16,17].…”

“…In another study, the degradation of organic carbon and disinfection of pathogenic bacteria depended on UV light and shock waves produced by plasma discharges [15,16,17]. Chiemchaisri et al [18] found an RE with respect to FC in the range of 96-98% and an RE with respect to TC in the range of 52-98% using process floating media filter-microfiltration combined with coagulation [18].…”

Degradação Do Corante Alaranjado De Metila via Oxidação Avançada Catalisada Por Tio2 Utilizada Para Tratamento De Efluente

“…Desse modo, os elétrons, que são os principais agentes formadores de espécies quimicamente ativas são gerados em maior quantidade o que aumenta a probabilidade de mais reações por impacto (Cadorni, 2009). Todavia, há um limite no aumento da potência, pois, a produção em excesso de NOx irá também competir com o consumo de átomos de oxigênio, provocando a redução da formação de radicais hidroxila e a redução da quantidade de ozônio disponível no sistema (Tang et al, 2009).…”