Plasma assisted conversion of methane and carbon dioxide

已经提出了几种技术，包括催化和等离子体，以改进将甲烷和二氧化碳转化为有用的化学中间体的过程。介质阻挡放电(DBD)和滑动放电(GD)的转化率受放电功率、外加电压和催化剂的影响较大。Warswava集团在包括催化剂在内的非热等离子体应用领域的详细经验将与在布伦施韦格开发的一种新型等离子体源相结合。这种源由10μm范围内的电极(以及电极之间的距离)组成，允许产生和引导与DBD和GD不同放电特性的等离子体。此外，这些等离子体源的顺序排列是可能的，这允许在效率和选择性方面的显著改进。在布伦斯韦格获得的初步结果表明，许多主要产品，如C2H2、C2H4、C2H6、CH3COOH、CH3OH、HCHO、CO、H2的生成效率可远高于10%。由于放置在等离子体放电中的催化剂对产物分布有显著影响，因此可以预期得到比已观察到的更高的产物产率。产物的形成机理尚不清楚，将使用详细的分析方法，包括在线质谱仪、GC、激光诱导荧光、FT-IR、光学发射光谱(OES)和腔振荡法(CRD)。我们将评估这两种等离子体技术的优缺点。将确定和优化合适的技术或两者的组合。采用等离子体-催化耦合过程的甲烷二氧化碳重整反应，可以通过一步操作获得包括乙烯和甲醇在内的理想产品。选择的过程将是简单的，表现出低碳生产，并且不像费舍尔-特罗普施那样能源密集型。有些产物(CH3COOH、CH3OH、HCHO)甚至可能是液体。

Several technologies including catalysis and plasma have already been proposed to improve the process involving conversion of methane and carbon dioxide into useful chemical intermediates. The conversions in dielectric-barrier discharges (DBD) or in gliding discharges (GD) were influenced significantly by discharge power, applied voltage, and catalysts. The detailed experience of the Warswava group in this field of non-thermal plasma applications including catalysts will be combined with a novel plasma source developed in Braunschweig. That source consists of electrodes (and distances between the electrodes) in the 10μm range allowing the generation and steering of plasmas at different discharge properties compared to DBD and GD. In addition, a sequential arrangement of these plasma sources is possible which allows a significant improvement in both efficiency and selectivity. The operating pressure can be as high as that of ambient air.Preliminary results obtained in Braunschweig show that many of the main products, C2H2, C2H4, C2H6, CH3COOH, CH3OH, HCHO, CO, H2, can be generated with efficiencies much better than10%. Since a catalyst placed in the discharges of the plasma affects the product distributions significantly, an even higher product yield than already observed can be expected. The mechanisms of product formation are still not understood and detailed analytics will be used, including on-line mass spectrometry, GC, laser induced fluorescence, FT-IR, optical emission spectroscopy (OES), and Cavity-Ring-Down (CRD) spectroscopy. The merits and drawbacks of either plasma technique will be assessed. The suitable technique or a combination of both will be identified and optimized. The CO2 reforming of methane using plasma-catalytic coupled process may be a source of desired products including ethylene and methanol, by one-stage operation. The selected process will be simple, exhibits low carbon production, and is not as energy intensive as Fischer-Tropsch. Some products (CH3COOH, CH3OH, HCHO) might even be found as a liquid.