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A gliding arc discharge (GAD) plasma reactor was developed for partial oxidative reforming (POR) H 2 production. Air was used as carrier gas and oxidant. The effects of the molar ratio of oxygen to carbon(O/C), input power and residence time on POR reaction were investigated. Under O/C ratio 0.75, input power 35 W and residence time 35 s, the energy yield of H 2 was 68.7 L/kWh and the main products were H 2 and CO. The GAD plasma was diagnosed with OES. A zero-dimensional(0-D) reaction kinetic model of was established. The simulation results were consistent with the experimental ones. The mechanism of C 12 H 26 conversion, the generation and consumption of products were discussed in detail. The experiment results were in good agreement with the simulated ones. The primary path of n -dodecane conversion was the direct cracking reaction and H 2 mainly derived from the recombination reaction between H atom and CH 4 , C 3 H 6 and C 2 H 6. [Display omitted] • A GAD reactor was used for POR of n -dodecane for hydrogen production. • A 0-D kinetic model was developed to explore the mechanism. • The results of OES were used to analyze the generation and consumption of substances. • The direct cracking reaction contributes the most to the n -dodecane conversion. [ABSTRACT FROM AUTHOR]

n-dodecane steam reforming (SR) process was investigated from both experimental and modelling views in gliding arc plasma. The effects of water-carbon molar ratio, n-dodecane concentration, input power and residence time on the conversion, yield, energy efficiency EE(C 12 H 26) and hydrogen energy yield EY(H 2) were revealed. The most dominant spectral lines detected by optical emission spectroscopy (OES) are CN violet and H α (3d2D-2p2p0). The highest yields of H 2 and CO are 50.1% and 49.9%, respectively. A zero-dimension reaction kinetic model containing 105 species and 793 reactions was developed for the SR process. Using CHENKIN-PRO, the presumable reaction pathways of n-dodecane, H 2 , CO, H 2 O and CO 2 were described in detail. H 2 and CO were produced mainly through reaction C 2 H 4 + H ⇌ C 2 H 3 + H 2 and reaction HCCO + H ⇌ C H 2 (S) + CO. [Display omitted] • Experimental and modelling study of n-dodecane steam reforming in a GAD plasma reactor. • A 0-D model was found to describe the main pathways of reaction processes. • The highest yields of H 2 and CO are 50.1% and 49.9%, respectively. • Reaction pathways of n-dodecane, H 2 , CO, H 2 O and CO 2 were described in detail. [ABSTRACT FROM AUTHOR]

The release of antibiotics that are difficult to degrade by themselves into the environment have received increasing attention because they have posed great threat to natural ecosystem and human health. Sodium persulfate (PS) is used to treat organic wastewater because of its strong oxidation, but it needs to be activated. Dielectric barrier discharge (DBD) can product stable gas discharge plasma that is suitable for activating PS. The synergistic degradation process of levofloxacin (LFX) by air DBD plasma with PS were investigated. The effects on the degradation ratio and energy efficiency of LFX were studied, including input power, air flow rate, original concentration, discharge spacing, and PS dosage. The degradation kinetics and synergistic factors were calculated under different PS additions. After plasma alone treatment 45 min, the maximum degradation ratio of LFX was 58.74 % and 88.63 % via plasma alone and plasma synergistic with PS under 15 W input power and 50 mg·L−1 LFX original concentration. The energy efficiency, the first-order reaction rate constant and the synergistic factor SI was 0.1532 g·(kW·h)−1, 4.116 × 10−2 min−1 and 1.64, respectively. The change of ozone concentration in the reaction system after adding PS was measured. The effects on the synergistic degradation of LFX of two radical scavengers, methanol (MeOH), and tert -butanol (TBA), were investigated. After calculation, the contribution ratios of ·OH and SO 4 -· were 48.08 % and 26.97 %, respectively. The intermediate products were analyzed by LC-MS in the decomposition process of LFX, and the probable decomposition pathway of LFX was presented. [Display omitted] • Degradation of LFX by DBD alone or in synergy with PS was investigated. • The effects of process parameters and PS on LFX degradation were studied. • The synergistic degradation rate was 88.63 % under higher concentration of LFX. • ·OH, SO 4 - and O 3 are the main oxidative active substances for the degradation of LFX. • Degradation pathway was proposed based on intermediate analysis with UV-Vis & LC-MS. [ABSTRACT FROM AUTHOR]

The exploration of novel technologies to reduce the air pollution and greenhouse gas emissions has been of great interest. Gliding arc plasma reformer at atmospheric pressure has been developed for converting n-heptane to hydrogen. The system has been evaluated by H 2 yield and energy yield via continuous n-heptane oxidative reforming at room temperature. Effects of some process parameters (discharge gap, input power, residence time, and O/C) have been studied on the reaction performance. The maximum H 2 yield and energy yield are 50.1% and 94.5 L (kW h)−1. To investigate the role of inert gas (N 2 , Ar) in the plasma oxidative reforming system, the performance of C 7 H 16 /air, C 7 H 16 /N 2 /O 2 /Ar and C 7 H 16 /O 2 /Ar have been investigated. The results show that N 2 (B3Π g) and Ar∗ can accelerate the formation of active oxygen species (such as O+, O (1D) and O). The presence of active oxygen species promotes the progress of the oxidative reforming reaction. What's more, N 2 (B3Π g) is also conducive to the direct conversion of n-heptane. The reaction mechanism of hydrogen production from gliding arc plasma oxidative reforming of n-heptane was proposed based on the analysis of the OES and GC–MS. Image 1 • H 2 production from n-heptane reforming in gliding arc plasma was investigated. • The maximum energy yield 94.5 L (kW· h)−1 and yield 50.1% of H 2 were obtained. • The N 2 (B3Π g), O (1D), O+, O play vital role in n-heptane oxidative reforming. • The reaction mechanism was proposed based the analysis of OES and GC-MS. [ABSTRACT FROM AUTHOR]