Non-thermal Dielectric Barrier Discharge Plasma Research Articles

Potential of Nonthermal Atmospheric-Pressure Dielectric Barrier Discharge Plasma for Inhibition of Athelia rolfsii Causing Southern Blight Disease in Lettuce

Athelia rolfsii is one of the most destructive and aggressive fungal pathogens worldwide and causes southern blight disease of lettuce. A nonthermal atmospheric-pressure dielectric barrier discharge (DBD) plasma has attracted interest as an alternative control method to chemical usage because of its antimicrobial activity. Exposure of A. rolfsii to DBD plasma for 5, 10, 15, and 20 min resulted in in vitro fungal inhibition of mycelial discs and sclerotia. The results showed that DBD plasma exposure for 10 min completely inhibited fungal growth of mycelial discs, whereas exposure for over 20 min was required to inhibit the hyphal growth of sclerotia. Scanning electron microscopy (SEM) observations of mycelia and sclerotia abnormalities revealed laceration and damage of both mycelia and sclerotia. In addition, disease incidence and severity were reduced in mycelial and sclerotia inoculation following DBD plasma exposure for 15 and 20 min, respectively, compared with the positive control. In conclusion, the DBD plasma demonstrates antifungal activity against A. rolfsii via inhibition of fungal growth and reduction in disease incidence and severity. Therefore, DBD plasma has the potential to be applied in controlling southern blight disease of lettuce.

Dielectric barrier discharge plasma catalysis as an alternative approach for the synthesis of ammonia: a review.

Numerous researchers have attempted to provide mild reactions and environmentally-friendly methods for NH3 synthesis. Research on non-thermal plasma-assisted ammonia synthesis, notably the atmospheric-pressure nonthermal plasma synthesis of ammonia over catalysts, has recently gained attention in the academic literature. Since non-thermal plasma technology circumvents the existing crises and harsh conditions of the Haber-Bosch process, it can be considered as a promising alternative for clean synthesis of ammonia. Non-thermal dielectric barrier discharge (DBD) plasma has been extensively employed in the synthesis of ammonia due to its particular advantages such as the simple construction of DBD reactors, atmospheric operation at ambient temperature, and low cost. The combination of this plasma and catalytic materials can remarkably affect ammonia formation, energy efficiency, and the generation of by-products. The present article reviews plasma-catalysis ammonia synthesis in a dielectric barrier discharge reactor and the parameters affecting this synthesis system. The proposed mechanisms of ammonia production by this plasma catalysis system are discussed as well.

수중 비열 유전체장벽 방전 플라즈마로 처리한 양식장 배출수의 수질 변화 특성

The purpose of this study is to evaluate the effects of underwater non-thermal Dielectric Barrier Discharge Plasma(DBD plasma) on fish farm effluent. This experiment was conducted in the DBD plasma generator, and the voltages given to generate DBD plasma were 11.6 kV and 23.1 kV. The measurement intervals were 0, 1, 5, 10 and 15 minutes. As a result of the experiment, the change in water quality was proportional to the strength of the voltage and the treatment time. At 23.1 kV for 15 minutes, the water temperature was increased to 51.1%, the pH was decreased by 26.2%, the dissolved oxygen was reduced to 50.3%, the chemical oxygen demand was reduced to 19.1% and the suspended solids was decreased 17.9%. NH₄SUP+/SUP-N was decreased by 95.8%, while NO₂SUP-/SUP-N and NO₃SUP-/SUP-N were increased by 851.8% and 170.2%. The total bacteria number contained in the discharge water was removed 100% at 23.1 kV for 15 minute, and the coliform group was sterilized up to 100% at 23.1 kV for 10 minute. The DBD plasma technology was found to reduce the organic pollutants and have high sterilization power against microorganisms in fish farm effluent.

Bioactive Nonthermal Biocompatible Plasma Enhances Migration on Human Gingival Fibroblasts.

This study hypothesizes that the application of low-dose nonthermal biocompatible dielectric barrier discharge plasma (DBD-NBP) to human gingival fibroblasts (HGFs) will inhibit colony formation but not cell death and induce matrix metalloproteinase (MMP) expression, extracellular matrix (ECM) degradation, and subsequent cell migration, which can result in enhanced wound healing. HGFs treated with plasma for 3min migrate to each other across the gap faster than those in the control and 5-min treatment groups on days 1 and 3. The plasma-treated HGFs show significantly high expression levels of the cell cycle arrest-related p21 gene and enhanced MMP activity. Focal adhesion kinase (FAK) mediated attenuation of wound healing or actin cytoskeleton rearrangement, and plasma-mediated reversal of this attenuation support the migratory effect of DBD-NBP. Further, this work performs computer simulations to investigate the effect of oxidation on the stability and conformation of the catalytic kinase domain (KD) of FAK. It is found that the oxidation of highly reactive amino acids (AAs) Cys427, Met442, Cys559, Met571, Met617, and Met643 changes the conformation and increases the structural flexibility of the FAK protein and thus modulates its function and activity. Low-dose DBD-NBP-induces host cell cycle arrest, ECM breakdown, and subsequent migration, thus contributing to the enhanced wound healing process.

Improved hydrogenation process for margarine production with no trans fatty acid formation by non-thermal plasma with needle-in-tube configuration

Non-thermal dielectric barrier discharge (DBD) plasma with needle-in-tube configuration was used to improve hydrogenation reaction for trans -fat free margarine production. Refined palm olein was used as raw material with operating conditions at ambient pressure, room temperature (29 °C) and no catalyst. Effects of hydrogen gas (H 2 ) concentration, input power, gas flow rate, discharge gap size and reaction time on fatty acid compositions and properties of hydrogenated refined palm olein after plasma treatment was evaluated. Lowest iodine value (IV) was achieved with reduction from 60.75 to 23.56 with increase in saturated fatty acid composition from 40.82 ± 0.05 to 68.70 ± 0.07% and decrease in unsaturated fatty acid composition from 59.11 ± 0.12 to 31.39 ± 0.01% under the condition of 0.5 L/min gas flow rate with 100% H 2 , 40 W input power, 0.5 cm gap size and 15 h reaction time. In addition, no trans -fat was detected by GC-MS analysis. Slip melting point (SMP) was increased from 9.33 ± 0.5 to 36.33 ± 0.5 °C. Acid value (AV) was reduced from 0.47 ± 0.02 to 0.32 ± 0.03 mg KOH/g oil. Texture of produced margarine was similar to that of commercial one. Generated hydrogen free radicals were hypothesized to perform hydrogenation by reacting with carbon-carbon double bonds (π-bonds), converting poly- and monounsaturated fatty acids into saturated ones. This highly effective catalyst-free plasma hydrogenation system can be used as alternative, environmentally friendly and economically feasible method to produce trans -fat free margarine. • Production of trans -fat free margarine via non-thermal plasma hydrogenation of palm olein. • Highly environmental-friendly, requiring no catalyst under low temperature and pressure. • Reduced acid value provides increased storage time and longer shelf life.

The effect of dual dielectric barrier discharge non-thermal plasma on the emission characteristics of diesel engine

Diesel engine have been applied to transportation due to its high efficiency, high output power, and high reliability. However, the emissions of diesel engines have become a serious problem and various technologies have been applied to reduce such emissions. Non-thermal plasma (NTP) is a notable potential measure for diesel engine emission control. The research investigated the effect of double dielectric barrier discharge (DDBD) NTP on diesel engine emission with different discharge voltages and duty ratios. The results shown that CO emission increases as the discharge voltage and duty ratio increases, with a maximum increasing rate of 8.59%. However, NOX, formaldehyde, acetaldehyde, VOCs, and PM2.5 emissions reduced, with a maximum reduction rate of 65.97%, 34.65%, 30.73%, 35.94%, and 85.21%, respectively. The research found that NTP can be used to control diesel engine emission, more importantly, it can achieve the reduction of NOX and PM emission simultaneously.

Identification of Reactive Species Produced by Surfaces Dielectric Barrier Discharge Nonthermal Plasma with Gas Sources Variation (Air, N2, O2) to Kill Bacteria

Non-thermal plasma is one of the new techniques that is being focused on in the medical world, one of which is used for sterilization because non-thermal plasma is known to have a bactericidal effect. Reactive species produced by non-thermal plasma are antimicrobial. One factor affecting plasma species' reactive composition is the gas source used. Therefore, this study aimed to determine the effect of reactive species produced from non-thermal plasma generation of SDBD using different gas sources, namely free air, oxygen, and nitrogen, in treating Escherichia Coli bacteria. The gas flow used is 1 liter/minute. Reactive species produced by plasma were characterized using Optical Emission Spectrometry (OES). SDBD Non-thermal plasma treatment for Escherichia Coli bacteria samples was repeated three times for each treatment, and then the Anova test was performed. The results of this study indicate that bacterial death at the decontamination level depends on the composition of the gas used during treatment. Plasma using an O2 gas source has a more effective inactivation ability, namely 6 x 107 CFU/ml, compared to the control, which is 409 x 107 CFU/ml. At the same time, the treatment results with free air and nitrogen gas sources were 6.33 x 107 CFU/ml and 41.67 x 107 CFU/ml. These results indicate that the composition of ROS and RNS influences bacterial inactivation, where ROS is more effective in inactivating bacteria than RNS

Synergistic degradation of aqueous p-nitrophenol using DBD plasma combined with ZnO photocatalyst

In this study a dielectric barrier discharge non-thermal plasma (DBD-NTP) reactor was combined with ZnO nanoparticles to degrade p-nitrophenol (PNP) in aqueous solution. When the plasma process was combined with ZnO nanoparticles an obvious improvement was obtained in PNP removal efficiency. this was seemingly due to activation of ZnO photocatalysts under the UV light produced in discharge region. The results showed that addition of the optimum amount of ZnO nanoparticles (250 mg/L) to the plasma reactor could increase the removal efficiency from 49 % to 91 %, whereas the UV/ZnO photocatalytic process alone only lead to 12 % PNP removal. This is indicative of the synergistic enhancement of PNP degradation efficiency in the combined NTP-ZnO process rather than simply an additive effect. The effects of intial solution pH, applied voltage, and initial PNP concentration were also investigated on the sole NTP and NTP-ZnO processes in terms of removal efficiency. Alkaline solution conditions, and lower initial PNP concentration favored both processes, while the applied voltage of 13 kV yielded the optimum PNP removal. Furthermore, higher total organic carbon (TOC) removal and higher kinetic constant of PNP degradation was achieved in the plasma system coupled with ZnO photocatalysis. Energy consumption analysis revealed that the NTP-ZnO process is 4.25 times more energy efficient than the sole plasma process which could be a major step towards industrial utilization of plasma treatment technologies.

Organic pollutants degradation using plasma with simultaneous ammonification assisted by electrolytic two-cell system

Atmospheric non-thermal dielectric barrier discharge (DBD) plasma has gained considerable attention due to its cost-efficiency, environmental friendliness, and simplicity. However, certain deficiencies restrict its broad application. Herein, the DBD plasma was used to disrupt three model pharmaceutically active compounds (PhACs), sulfamethoxazole (SMX), ibuprofen (IBP), and norfloxacin (NFX), by varying parameters, such as gas type (Ar, N2, O2, and air) and flow rate (1–4 L min−1). The air plasma discharge had the highest degradation efficiency, and the air flow rate was optimized at 2 L min−1. However, only 10% of IBP was removed by the sole plasma, whereas NFX and SMX were entirely removed after 30 min. Since the air plasma discharge generates reactive oxygen and nitrogen species in a chained reaction, the remaining NO2− and NO3− in the aqueous phase were problematic. Therefore, by coupling plasma with electrolysis using Cu/reduced Cu nanowire (R-CuNw) as the anode/cathode, all three PhACs were removed within 30 min, and NO2− and NO3− were completely reduced to NH3 with cathodic reduction. Moreover, the electrical energy per order (EEO, 0.04 kWh L−1) and treatment cost (0.003 USD L−1) were much lower than those of the single system. This system demonstrates great potential for water remediation, and the production of NH3 as a value-added by-product remarkably improves its practicality and is of great importance in agriculture and energy-related industries.

Preliminary evaluation of surface dielectric barrier discharge non-thermal plasma for reforming syngas derived from a downdraft gasifier

Measurement by NASA has indicated an increase in carbon dioxide levels in the air from 381 to 417 ppm from 2006 to 2022. Gasification is a proven technology that can reduce carbon accumulations in the air as it can convert renewable organic materials into syngas, including hydrogen as future clean energy fuel, and sequester carbon in the form of biochar. However, tar in syngas still remains a challenge, requiring complex gas cleaning system. This study presents a critical evaluation of reforming syngas directly from a gasifier for increased hydrogen (H2) production while reducing syngas tar using dielectric barrier discharge (DBD) plasma. Results showed an increase in H2 (from 4.8 to 9.5 vol%) with a slight increase in CO (from 31.9 to 34.7 % vol.%) and a decrease in heavier hydrocarbons, such as C2H6 (from 8.5 to 4.6 vol%). Syngas tar decreased by 88 %, from 25 to 3 g/Nm3. At steady-state operation, the power consumption for operating the plasma system was 160 W, resulting in energy density of 0.19 kWh/m3. The outcome of this study is critical for further development of existing gasification systems capable of treating diverse organic feed streams, including biomass, coal, municipal solid waste (MSW), and plastic.

Catalytic gasification of rice hull by dielectric barrier discharge non-thermal plasma over potassium catalyst

Dielectric barrier discharge (DBD) non-thermal plasma was used for gasification of rice hull. And the gasification efficiency, gas production performance and gasification productions of rice hull were studied in the different atmosphere of the DBD gasification. The effect of the potassium metal on DBD gasification of rice hull was investigated and the catalytic mechanism of potassium was studied by density functional theory calculation. It was found that the gasification efficiency of rice hull by DBD in CO2 atmosphere is up to 87.14%, which is higher than that in the N2 atmosphere. The implantation of the potassium metal can also improve the DBD gasification efficiency, and promote the generation of H2 and CH4. The rice hull loaded with 3% potassium had the best gasification in the CO2 atmosphere. Almost no tar was found during the DBD gasification of rice hull. N2 adsorption and desorption, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) were used to investigate the properties of the carbon materials, which was generated from the rice hull gasification. The carbon material which was produced by DBD gasification in CO2 atmosphere had large specific surface area and abundant functional groups. It can be used as catalyst carrier and other fields.

Synergistic degradation of the aqueous antibiotic norfloxacin by nonthermal plasma combined with defective titanium dioxide exposed {0 0 1} facets

The wide band gap of titanium dioxide (TiO2) photocatalyst leads to its narrow optical response, which seriously affects the application of TiO2. In order to enhance its catalytic efficiency, defective TiO2-exposed {001} facets (TiO2-x) was prepared and applied to pollutants degradation by combing with the dielectric barrier discharge nonthermal plasma (DBD-NTP), so as to use the ultraviolet light and other active species produced by DBD-NTP. Taking aqueous norfloxacin (NOR) as a model pollutant, the degradation performance of NOR by DBD-NTP and TiO2-x was evaluated, the synergistic catalytic mechanism and degradation pathways of NOR based on heterogeneous catalysis were proposed. An artificial neural network model based on genetic algorithm optimization (GA-ANN) was constructed to predict the NOR degradation efficiency. The characteristics of TiO2-x were characterized, and the effects of influencing factors on the NOR degradation efficiency were investigated. The results showed a significant synergistic catalytic effect in NOR degradation by DBD-NTP combined with TiO2-x. The synergistic catalytic effect substantially increased with increasing TiO2-x dosage, and the synergistic factor increased by 3.3 times. The reactive agents 1O2, OH, O2−, h+ and e− played an essential role in NOR degradation, with the contribution of 1O2 being the most significant. TiO2-x had good catalytic stability. The degradation pathways of NOR mainly included breakage of the piperazine ring and quinoline ring, decarboxylation, benzene ring defluorination and mineralization. The established GA-ANN model showed high accuracy (mean square error = 0.0016, correlation coefficient = 0.9956) and could be used to predict the degradation efficiency of aqueous NOR.

Biogas reforming for hydrogen-rich syngas production over a Ni–K/Al2O3 catalyst using a temperature-controlled plasma reactor

Plasma-enhanced catalytic biogas reforming for hydrogen-rich syngas production over a Ni–K/Al2O3 catalyst was investigated using a tabular dielectric barrier discharge non-thermal plasma reactor. To better understand the plasma catalysis synergy at elevated temperatures, we compared different reaction modes: plasma catalysis, plasma alone, and catalysis alone in a reaction temperature range of 160–400 °C. The combination of Ni–K/Al2O3 and plasma produced synergistic effects. Notably, the plasma-catalytic synergy was temperature-dependent and varied at different reaction temperatures. Using plasma catalysis, the maximum conversion of CH4 and CO2 (31.6% and 22.8%, respectively) was attained over Ni–K/Al2O3 at 160 °C, while increasing the reaction temperature to 340 °C noticeably enhanced the H2/CO ratio to 2.71. Moreover, compared to plasma-catalytic biogas reforming at 160 °C, increasing the reaction temperature to 400 °C suppressed biogas conversion with dramatically reduced coke formation on the Ni–K/Al2O3 surface from 6.81 wt% to 3.37 wt%.

Oxidative removal of hexane from the gas stream by dielectric barrier discharge reactor and effect of gas environment

The removal of hexane from a gas stream using a dielectric barrier discharge (DBD) reactor was conducted at ambient temperature and atmospheric pressure. The role of N2, dry and humidified air carrier gases were investigated in terms of removal efficiency and product selectivity. The oxygen concentration was also varied over the range of 0 – 21% at constant power and residence time in an N2O2 mixture for further insight into oxygen's role. A semi-empirical model of NTP-decomposition in the presence of O2, N2 and H2O is proposed. It was observed that hexane removal efficiency and product selectivity increased with increasing plasma power, regardless of the carrier gas used. The maximum removal efficiency (hexane) was 94.4% in the humidified air carrier gas. The introduction of water vapour with a relative humidity of 25% at 20 °C in the plasma DBD system significantly increased the hexane removal efficiency and CO2 selectivity (84.7%) while eliminating the production of solid residue and O3. This was probably due to the action of OH radicals. Increasing O2 concentration from 0 to 21% increased the removal efficiency and CO2 selectivity due to the generation of oxygen radicals. The results imply that the decomposition of hexane by non-thermal plasma DBDs is dominated by the effect of OH and O radicals. A semi-empirical model shows that the non-thermal plasma decomposition of hexane is first order. The DBD reactor has been demonstrated to be an effective and promising technology for removing hexane emissions from air streams. The effects of N2, O2 and H2O have been quantified, and mechanisms for their action proposed.

Plasma-assisted removal of methanol in N2, dry and humidified air using a dielectric barrier discharge (DBD) reactor.

In this work, a non-thermal plasma dielectric barrier discharge (DBD) was used to remove methanol from ambient air. The effects of carrier gases (N2, dry and humidified air), power (2–10 W), inlet concentration (260–350 ppm), and residence time (1.2–3.3 s) were investigated to evaluate the performance of the plasma DBD reactor in terms of removal efficiency, product selectivity and reduction of unwanted by-products at ambient temperature and atmospheric pressure. It was found that the conversion of methanol increased with power and residence time regardless of the carrier gas used. However, the removal efficiency decreased with the increasing concentration of CH3OH. Almost complete removal of methanol (96.7%) was achieved at 10 W and a residence time of 3.3 s in dry air. The removal efficiency of methanol followed a sequence of dry air > humidified air > N2 carrier gas. This was due to the action of the O radical in dry air, which dominates the decomposition process of the plasma system. The introduction of water vapour into the DBD system decreased the removal efficiency but had a number of significant advantages: increased CO2 selectivity and yield of H2, it significantly reduced the formation of O3, CO and higher hydrocarbons. These influences are probably due to the presence of potent OH radicals, and the conversion pathways for the various effects are proposed. It is important to note that no solid residue was formed in the DBD reactor in any carrier gas. Overall, this research indicates that methanol can be almost completely removed with the correct operating parameters (96.7% removal; 10 W; 3.3 s) and shows that humidification of the gas stream is beneficial.

Synergistic catalytic degradation of ciprofloxacin using magnetic carbon nanomaterial/NiFe2O4 promoted cold atmospheric pressure plasma jet: Influence of charcoal, multi walled carbon nanotubes and walnut shell

BackgroundCurrently, water polluted to antibiotics such as ciprofloxacin (CIP) has been a main concern for the ecosystem and environment. Hence, the removal of these emerging contaminants is essential. MethodIn this research, a hybrid process including magnetic carbon nanomaterial/NiFe2O4 promoted atmospheric non-thermal dielectric barrier discharge plasma jet (APJ) as an environmentally friendly hybrid system was evaluated for eliminating CIP from polluted synthetic effluent. Multi walled carbon nanotubes (MWCNTs), activated carbon formed using charcoal (ChAC), and the walnut shell was applied as the carbonous source. Besides, to solve the separation problem, the charcoal, as optimum sample, was magnetized with NiFe2O4 (ChAC/NiFe2O4) using the treatment solvothermal route. Characterizations of all carbon materials were carried out by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda and vibrating-sample magnetometer analyses. FindingThe degradation amount for 80 mg/L CIP gained 48.8, 80.8, and 98.1% over APJ system + walnut shell, MWCNTs, and ChAC, respectively, after 90 min at 15 kVp-p output voltage and 0.05 g/L of catalyst loading. The results showed the ChAC/NiFe2O4 (87.2%) had less removal than ChAC (98.1%), but it has magnetic properties that can facilitate the separation problem.

Reduction of copper surface oxide using a sub-atmospheric dielectric barrier discharge plasma

Oxide layers on metal surfaces adversely affect processability and material properties in many industrial applications. Although several plasma-based approaches for deoxidation were investigated in the past, oftentimes they either work under conditions expensive to create or require long processing times. In this study, the deoxidation effect of a non-thermal dielectric barrier discharge plasma in an Ar/H2 gas mixture at 100 hPa and 20 °C was investigated on copper surfaces with a native oxide layer. The chemical structure of surfaces before and after deoxidation was analyzed by X-ray photoelectron spectroscopy (XPS). The results revealed that ∼98% of the surface lattice oxide Cu2O was reduced to Cu after around 20 s of plasma treatment, whereas all oxygen contaminants were almost completely removed from Cu surface after around 50 s. Additionally, the kinetics of the reduction of surface oxide was studied and a Johnson-Mehl-Avrami-Erofeev-Kholmogorov kinetic model was proposed. The analysis of the morphology of surfaces was performed with atomic force microscopy (AFM), showing minor changes in the roughness after deoxidation. Moreover, optical emission spectroscopy (OES) showed atomic hydrogen radicals in the plasma phase, which likely causes deoxidation effect.

Effect of Liquid Grounding Electrode on the NOx Removal by Dielectric Barrier Discharge Non-Thermal Plasma

In this paper, an experimental setup was established to study the influence of potassium chloride (KCL) solution as the ground electrode on the nitrogen oxides (NOx) removal efficiency in non-thermal plasma (NTP) generated by dielectric barrier discharging (DBD) reactor. The experimental results show that the KCL solution as the ground electrode has better stability and higher discharge intensity and it is a promising approach to improve NOx removal efficiency. The specific NOx removal efficiency is related to the power frequency, the concentration and temperature of the KCL solution. As the power frequency increases, the NOx removal efficiency first increases and then decreases, and a maximum value is reached at the power frequency of 8 kHz. The NO removal effect is improved as the concentration of the KCL solution increases, especially when the concentration is lower than 0.1 mol/L. Under the same KCL solution concentration and input energy density, the NOx removal efficiency is increased with the solution temperature. In particular, when the power discharge frequency is 8 kHz, the KCL solution concentration is 0.1 mol/L and the solution temperature is 60 °C, the NOx and NO removal efficiency reach 85.82% and 100%, respectively.

Antibacterial effects of non-thermal dielectric barrier discharge plasma against Escherichia coli and Vibrio parahaemolyticus on the surface of wooden chopping board

In this study, the effects of atmospheric dielectric barrier discharge (DBD) plasma treatment (1.1 kV, 43 kHz, 5–30 min, N2: 1.5 lpm) were investigated for the inactivation of Escherichia coli and Vibrio parahaemolyticus on wooden chopping board (WCB) surfaces. A reduction of 0.4–1.6 and 0.4–1.3 log CFU/coupon was observed for E. coli and V. parahaemolyticus, respectively, on the WCB surface by DBD plasma treatment. The first-order kinetics model was used to generate linear survival curves and calculate D-values and R2 for the bacteria; D-values were 41.0 min and 59.8 min, and R2 values were 0.94 and 0.97 for E. coli and V. parahaemolyticus, respectively. Based on these findings, DBD plasma could potentially serve as a new antimicrobial method for wooden cutting boards.

Efficient degradation of Bisphenol A by dielectric barrier discharge non-thermal plasma: Performance, degradation pathways and mechanistic consideration

The discharge of recalcitrant and persistent organic pollutants into the environment and subsequent adverse impacts on the ecosystem has aroused a great concern all over the world. In this study, dielectric barrier discharge (DBD) non-thermal plasma was employed to eliminate bisphenol A (BPA). The influences of several vital experimental parameters, including discharge voltage, initial pH of solution, and rate of water flow on degradation of BPA, were explored in detail. In addition, the real wastewater from pharmaceutical factory was utilized to test the oxidation performance of DBD system. 96.8% chemical oxygen demand removal was achieved using DBD system. Radical quenching experiment as well as electron paramagnetic resonance test demonstrated that •OH was the main reactive oxygen species for the degradation of BPA. Moreover, eight major BPA degradation intermediates were identified by UPLC-MS. Ultimately, based on the UPLC-MS test results, a possible degradation pathway of BPA was proposed.