Catalyst‐enhanced plasma oxidation of n‐butane over α‐MnO₂ in a temperature‐controlled twin surface dielectric barrier discharge reactor

Abstract

A twin surface dielectric barrier discharge is used for the catalyst‐enhanced plasma oxidation of 300 ppm n‐butane in synthetic air. Plasma‐only operation results in the conversion of n‐butane into CO and CO2. Conversion is improved by increasing the temperature of the feed gas, but selectivity shifts to undesired CO. α‐MnO2 is used as a catalyst deposited on the electrodes by spray coating with a distance of 1.5 mm between the uncoated grid lines and the square catalyst patches to prevent the inhibition of plasma ignition. The catalyst strongly influences selectivity, reaching 40% conversion and 73% selectivity to CO2 at a specific energy density of 390 J·L−1 and 140°C, which is far below the onset temperature of thermocatalytic n‐butane conversion.

A scalable twin surface dielectric barrier discharge system for pollution remediation at high gas flow rates

“…In both diagrams the measurements by Schücke et al , 21 Peters et al 23 and Gandhi et al 40 are shown for reference. Schücke et al use the same SDBD setup with a single electrode, a different plasma chamber, and a gas flow of 10 slm of synthetic air.…”

“…Peters et al 23 used the same SDBD and their setup is almost identical to the setup of Schücke et al Because Peters et al are using a similar plasma chamber and a synthetic air flow of 10 slm it is evident that both setups have almost the same energy density. The main difference is that Peters et al additionally use a catalyst (α-MnO 2 ).…”

“…Additionally, the fluid dynamics will be investigated in greater detail, because of its potential of increasing the total efficiency of the setup. As Peters et al 23 have shown, additional catalysts could enhance the selectivity and further research may be required in order to find suitable catalysts for the desired low temperature range and to enhance the conversion.…”

“…Peters et al performed studies on the n -butane conversion, selectivity and carbon balance using the same electrode with complementary α-MnO 2 deposited as catalyst. 23 All the results show a great potential for the VOC removal, but these single-electrode systems are limited to a maximum gas flow of 10 slm of synthetic air. Therefore, it is difficult to make a statement about the industrial relevance for large gas flows, that can reach 15 000 m 3 min −1 (ref.…”

Study of plasma parameters and gas heating in the voltage range of nondischarge to full‐discharge in a methane‐fed dielectric barrier discharge

“…DBDs can operate at atmospheric pressure, which is most suitable for practical applications [ 7 ] . Also, they are merged easily with catalytic packing materials, which opens new practical windows for the selective production of value‐added compounds [ 8 ] . In DBDs, when size of electrodes decreases the local electric field near them enhances.…”