Non-equilibrium plasma-assisted dry reforming of methane over shape-controlled CeO 2 supported ruthenium catalysts
Non-equilibrium plasma-assisted dry reforming of methane over shape-controlled CeO 2 supported ruthenium catalysts
复制标题
形状控制的 CeO 2 负载钌催化剂上非平衡等离子体辅助干重整甲烷
DOI：
10.1039/d3ta01196h
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发表时间：
2023
影响因子：
11.9
通讯作者：
Wang, Ruigang
中科院分区：
文献类型：
--
作者：
Ahasan, Md Robayet;Hossain, Md Monir;Ding, Xiang;Wang, Ruigang
在这份报告中，CeO 2和SiO2负载1重量%的Ru催化剂的合成和研究的甲烷干重整（DRM），通过引入非热等离子体（NTP）在介质阻挡放电（DBD）固定床反应器。从四极质谱（QMS）数据发现，在热催化DRM中引入非热等离子体比在仅热催化条件下促进更高的CH 4和CO2转化率和合成气（CO + H2）产率。根据H2-TPR、CO2-TPD和CO-TPD曲线，与不可还原的SiO2负载的Ru催化剂相比，可还原的CeO 2负载的Ru催化剂表现出更好的活性。例如，对于在350 °C下的等离子体辅助的热催化DRM，CO和H2的摩尔浓度分别为16%和9%，而对于热催化DRM，在相同温度下没有观察到明显的转化。在非平衡和非热等离子体条件下的高能电子、离子和自由基被认为有助于活化CH 4中的强C-H键和CO2中的C-O键，这显著提高了低温DRM反应期间的CH 4/CO2转化率。在450 °C下，与1 wt% Ru/CeO 2纳米立方体（40%CH4和30%CO2）相比，1 wt % Ru/CeO 2纳米棒样品显示出最高的催化活性，具有51%CH4和37%CO2转化率。这些结果清楚地表明，载体形状和还原度影响等离子体辅助DRM反应。这种增强的DRM活性归因于CeO 2纳米棒载体的表面化学和缺陷结构，其可以提供活性表面小面、更高量的移动的氧和氧空位以及其它表面缺陷。
In this report, CeO2 and SiO2 supported 1 wt% Ru catalysts were synthesized and studied for dry reforming of methane (DRM) by introducing non-thermal plasma (NTP) in a dielectric barrier discharge (DBD) fixed bed reactor. From quadrupole mass spectrometer (QMS) data, it is found that introducing non-thermal plasma in thermo-catalytic DRM promotes higher CH4 and CO2 conversion and syngas (CO + H2) yield than those under thermal catalysis only conditions. According to the H2-TPR, CO2-TPD, and CO-TPD profiles, reducible CeO2 supported Ru catalysts presented better activity compared to their irreducible SiO2 supported Ru counterparts. For instance, the molar concentrations of CO and H2 were 16% and 9%, respectively, for plasma-assisted thermo-catalytic DRM at 350 °C, while no apparent conversion was observed at the same temperature for thermo-catalytic DRM. Highly energetic electrons, ions, and radicals under non-equilibrium and non-thermal plasma conditions are considered to contribute to the activation of strong C–H bonds in CH4 and C–O bonds in CO2, which significantly improves the CH4/CO2 conversion during DRM reaction at low temperatures. At 450 °C, the 1 wt% Ru/CeO2 nanorods sample showed the highest catalytic activity with 51% CH4 and 37% CO2 conversion compared to 1 wt% Ru/CeO2 nanocubes (40% CH4 and 30% CO2). These results clearly indicate that the support shape and reducibility affect the plasma-assisted DRM reaction. This enhanced DRM activity is ascribed to the surface chemistry and defect structures of the CeO2 nanorods support that can provide active surface facets, higher amounts of mobile oxygen and oxygen vacancy, and other surface defects.