Dry reforming of methane over a Ni/Al2O3 catalyst in a coaxial dielectric barrier discharge reactor
Dry reforming of methane over a Ni/Al2O3 catalyst in a coaxial dielectric barrier discharge reactor
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DOI：
10.1088/0022-3727/44/27/274007
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发表时间：
2011-07
期刊：
影响因子：
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通讯作者：
X. Tu;H. J. Gallon;Bernard Nisol;Sven Stauss;V. Gibalov;G. Pietsch
中科院分区：
文献类型：
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作者：
X. Tu;H. J. Gallon;Bernard Nisol;Sven Stauss;V. Gibalov;G. Pietsch
研制了一种同轴双介质阻挡放电(DBD)反应器，用于等离子体催化甲烷和二氧化碳转化为合成气和其他有价值的产品。在甲烷放电中还原的负载型金属催化剂(Ni/Al_2O_3)被完全填充到放电区。研究了填充在气隙中的Ni/Al_2O_3催化剂对放电电学特性的影响。催化剂颗粒的引入导致放电行为从典型的丝状微放电转变为空间受限微放电和催化剂表面主要表面放电的组合。当还原后的催化剂在放电区装满时，CH4/CO2放电的击穿电压显著降低。分散在催化剂表面的导电Ni活性中心有助于放电的扩大和电荷转移的增强。此外，在还原的Ni/Al_2O_3催化剂上，当CH_4/CO_2=1，总流量为50mlmin−_1时，甲烷的等离子体催化干法重整反应具有较高的H_2选择性。有催化剂时，H_2/CO摩尔比从0.84增加到2.53。
A coaxial double dielectric barrier discharge (DBD) reactor is developed for plasma-catalytic conversion of CH4 and CO2 into syngas and other valuable products. A supported metal catalyst (Ni/Al2O3) reduced in a methane discharge is fully packed into the discharge region. The influence of the Ni/Al2O3 catalyst packed into the gas gap on the electrical characteristics of the discharge is investigated. The introduction of the catalyst pellets leads to a transition in discharge behaviour from a typical filamentary microdischarge to a combination of spatially limited microdischarges and a predominant surface discharge on the catalyst surface. It is also found that the breakdown voltage of the CH4/CO2 discharge significantly decreases when the reduced catalyst is fully packed in the discharge area. Conductive Ni active sites dispersed on the catalyst surface contribute to the expansion of the discharge and enhancement of charge transfer. In addition, plasma-catalytic dry reforming of CH4 is carried out with the reduced Ni/Al2O3 catalyst using a mixing ratio of CH4/CO2 = 1 and a total flow rate of 50 ml min−1. An increase in H2 selectivity is observed compared with dry CH4 reforming with no catalyst, while the H2/CO molar ratio significantly increases from 0.84 to 2.53 when the catalyst is present.