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The aim of this research work was to evaluate the possibility of upgrading the simulated biogas (70?% CH4 and 30?% CO2) for hydrogen-rich syngas production using a multi-stage AC gliding arc system. The results showed that increasing stage number of plasma reactors, applied voltage and electrode gap distance enhanced both CH4 and CO2 conversions, in contrast with the increases in feed flow rate and input frequency. The gaseous products were mainly H2 and CO, with small amounts of C2H2, C2H4 and C2H6. The optimum conditions for hydrogen-rich syngas production using the four-stage AC gliding arc system were a feed flow rate of 150?cm3/min, an input frequency of 300?Hz, an applied voltage of 17?kV and an electrode gap distance of 6?mm. At the minimum power consumption (3.3?×?10?18?W?s/molecule of biogas converted and 2.8?×?10?18?W?s/molecule of syngas produced), CH4 and CO2 conversions were 21.5 and 5.7?%, respectively, H2 and CO selectivities were 57.1 and 14.9?%, respectively, and H2/CO (hydrogen-rich syngas) was 6.9. The combination of the plasma reforming and partial oxidation provided remarkable improvements to the overall process performance, especially in terms of reducing both the power consumption and the carbon formation on the electrode surface but the produced syngas had a much lower H2/CO ratio, depending on the oxygen/methane feed molar ratio. The best feed molar ratio of O2-to-CH4 ratio was found to be 0.3/1, providing the CH4 conversion of 81.4?%, CO2 conversion of 49.3?%, O2 conversion of 92.4?%, H2 selectivity of 49.5?%, CO selectivity of 49.96?%, and H2/CO of 1.6.  相似文献   
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The objective of the present work was to study the reforming of simulated natural gas via the nonthermal plasma process with the focus on the production of hydrogen and higher hydrocarbons. The reforming of simulated natural gas was conducted in an alternating current (AC) gliding arc reactor under ambient conditions. The feed composition of the simulated natural gas contained a CH4:C2H6:C3H8:CO2 molar ratio of 70:5:5:20. To investigate the effects of all gaseous hydrocarbons and CO2 present in the natural gas, the plasma reactor was operated with different feed compositions: pure CH4, CH4/He, CH4/C2H6/He, CH4/C2H6/C3H8/He and CH4/C2H6/C3H8/CO2. The results showed that the addition of gas components to the feed strongly influenced the reaction performance and the plasma stability. In comparisons among all the studied feed systems, both hydrogen and C2 hydrocarbon yields were found to depend on the feed gas composition in the following order: CH4/C2H6/C3H8/CO2 > CH4/C2H6/C3H8/He > CH4/C2H6/He > CH4/He > CH4. The maximum yields of hydrogen and C2 products of approximately 35% and 42%, respectively, were achieved in the CH4/C2H6/C3H8/CO2 feed system. In terms of energy consumption for producing hydrogen, the feed system of the CH4/C2H6/C3H8/CO2 mixture required the lowest input energy, in the range of 3.58 × 10−18–4.14 × 10−18 W s (22.35–25.82 eV) per molecule of produced hydrogen.  相似文献   
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The title molecule, (iodobromo)triphenylarsenic(III), [As(BrI)(C6H5)3], has a dart shape, with the phenyl rings arranged in a propeller conformation [I—As—C—C 61.3 (4), 43.8 (4) and 54.1 (4)°]. There is no indication that the halogen atoms have mixed site occupancies. Packing forces displace the I atom away from one phenyl ring [I—As—C 117.3 (2)°] towards the other two [I—As—C 109.8 (2) and 108.3 (2)°] and produce an even more pronounced leaning of the terminal bromine [As—I—Br 174.78 (2)°].  相似文献   
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In this research, the reforming of simulated natural gas containing a high CO2 content under AC non-thermal gliding arc discharge with partial oxidation was conducted at ambient temperature and atmospheric pressure, with specific regards to the concept of the direct utilization of natural gas. This work aimed at investigating the effects of applied voltage and input frequency, as well as the effect of adding oxygen on the reaction performance and discharge stability in the reforming of the simulated natural gas having a CH4:C2H6:C3H8:CO2 molar ratio of 70:5:5:20. The results showed marked increases in both CH4 conversion and product yield with increasing applied voltage and decreasing input frequency. The selectivities for H2, C2H6, C2H4, C4H10, and CO were observed to be enhanced at a higher applied voltage and at a lower frequency, whereas the selectivity for C2H2 showed an opposite trend. The use of oxygen was found to provide a great enhancement of the plasma reforming of the simulated natural gas. For the combined plasma and partial oxidation in the reforming of CO2-containing natural gas, air was found to be superior to pure oxygen in terms of reactant conversions, product selectivities, and specific energy consumption. The optimum conditions were found to be a hydrocarbons-to-oxygen feed molar ratio of 2/1 using air as an oxygen source, an applied voltage of 17.5 kV, and a frequency of 300 Hz, in providing the highest CH4 conversion and synthesis gas selectivity, as well as extremely low specific energy consumption. The energy consumption was as low as 2.73 × 10−18 W s (17.02 eV) per molecule of converted reactant and 2.49 × 10−18 W s (16.60 eV) per molecule of produced hydrogen.  相似文献   
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The effect of stage number of multistage AC gliding arc discharge reactors on the process performance of the combined reforming and partial oxidation of simulated CO2-containing natural gas having a CH4:C2H6:C3H8:CO2 molar ratio of 70:5:5:20 was investigated. For the experiments with partial oxidation, either pure oxygen or air was used as the oxygen source with a fixed hydrocarbon-to-oxygen molar ratio of 2/1. Without partial oxidation at a constant feed flow rate, all conversions of hydrocarbons, except CO2, greatly increased with increasing number of stages from 1 to 3; but beyond 3 stages, the reactant conversions remained almost unchanged. However, for a constant residence time, only C3H8 conversion gradually increased, whereas the conversions of the other reactants remained almost unchanged. The addition of oxygen was found to significantly enhance the process performance of natural gas reforming. The utilization of air as an oxygen source showed a superior process performance to pure oxygen in terms of reactant conversion and desired product selectivity. The optimum energy consumption of 12.05 × 1024 eV per mole of reactants converted and 9.65 × 1024 eV per mole of hydrogen produced was obtained using air as an oxygen source and 3 stages of plasma reactors at a constant residence time of 4.38 s.  相似文献   
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The heteroditopic receptor 2 containing a crown ether and amidoferrocence groups was synthesized and the binding abilities with various anions are reported in the presence and absence of metal cations. In the presence of Na+, 2 showed positive co-operative binding towards Br with the binding affinity Kass = 16,096 M−1. Therefore, receptor 2 showed a switched-on binding for Br in the presence of Na+ and a switched-off binding in the absence of Na+. Compound 2 was also found to sense Cl and Br electrochemically.  相似文献   
8.
In this work, a mini-gliding arc discharge reactor was employed for the reforming of methane under ambient temperature and pressure operation. Acetylene and hydrogen were produced dominantly with high selectivities of ~70?C90 and ~75%, respectively. The results showed that both methane conversion and product selectivities depended strongly on various operating parameters, including feed methane concentration, feed flow rate, electrode gap distance, residence time, and the presence of a reforming catalyst (as a function of catalyst distance). The Ni catalyst-loaded porous alumina-silica plate was used to study the catalytic effect on the process performance at various residence times. A considerable enhancement of methane conversion and product yields was achieved in the combined plasma-catalytic system, particularly at a longer residence time. The catalyst distance, or packing position of catalyst plate, was also found to be an important factor affecting the process performance of the combined plasma-catalytic methane reforming. The closer catalyst distance led to the greater methane conversion because of the greater possibility of adsorption?Cdesorption interactions of excited gaseous species on the catalyst surface to enhance subsequent reactions.  相似文献   
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