The Effect of Temperature on the Plasma-Catalytic Destruction of Propane and Propene: A Comparison with Thermal Catalysis

Abstract

A comparison has been made of plasma-catalysis with thermal-catalysis and plasma alone for the removal of low concentrations of propane and propene from synthetic air using a one-stage, catalyst-in discharge configuration. In all cases, plasma-catalysis produces better hydrocarbon destructions (*40%) than thermal catalysis at low temperatures. At higher temperatures, little difference is observed between plasma-catalytic and thermal-catalytic operation. Plasma operation by itself had a similar effectiveness to plasma-catalysis at low temperatures but was significantly lower (up to 50%) as the temperature was raised. By examining the form of the temperature dependence for the plasma-catalytic destruction processes, it is possible to phenomenologically distinguish two contributions to the destruction; one that is specifically plasma-induced and another (at higher temperatures) in which both plasma and thermal activation have similar mechanisms.

Fundamental Properties and Applications of Dielectric Barrier Discharges in Plasma‐Catalytic Processes at Atmospheric Pressure

“…There is no detailed information available so far about the mechanisms inducing the shift in the catalytic onset temperature, but it was stated that plasma-catalytic systems for both IPC and PPC configurations are always found and reported to be more efficient than thermal catalysis [92]. Similar results were reported by Blackbeard et al [11] for the plasma-catalytic oxidation of propane and propene over supported MnO 2 and Pt catalysts. By using a heatable packed-bed reactor in an IPC configuration, up to 40 % higher degrees of conversion were obtained at lower temperatures than in thermal catalysis.…”

“…One of the most promising approaches to overcome these drawbacks is the combination of the nonthermal plasma discharge with a heterogeneous catalyst, which is called plasma catalysis, plasma-assisted catalysis or plasma-enhanced catalysis. It can lead to synergistic effects and conversion efficiencies and yields superior to the theoretical sum of plasma and catalysis applied separately [11,12,22]. In general, two concepts for plasma-assisted catalysis can be distinguished depending on the position of the catalyst relative to the plasma.…”

“…Similar results were reported by Blackbeard et al. for the plasma‐catalytic oxidation of propane and propene over supported MnO 2 and Pt catalysts. By using a heatable packed‐bed reactor in an IPC configuration, up to 40 % higher degrees of conversion were obtained at lower temperatures than in thermal catalysis.…”

“…Especially the combination of a nonthermal atmospheric pressure plasma source with a heterogeneous catalyst is of great interest for chemical transformations in gas or air treatment. Plasma catalysis can achieve improved performance in comparison to both methods applied separately , . For example, the reactivity of the plasma may prevent catalyst deactivation or reduce catalyst poisoning.…”

Plasma catalysis: A solution for environmental problems

“…This could either be by electrons or photons created directly by the discharge (electron-induced processes and production of electrons have only a slight temperature dependence [15]) or by the production of active species such as atomic oxygen or ozone which can then adsorb onto the catalyst surface. For the strongly temperature-dependent curve, thermal activation of the catalyst becomes more important, overtaking the contribution of the plasma-activated processes [16].…”