Improved performance of non-thermal plasma reactor during decomposition of trichloroethylene: Optimization of the reactor geometry and introduction of catalytic electrode

Abstract

The decomposition of trichloroethylene (TCE) by non-thermal plasma was investigated in a dielectric barrier discharge (DBD) reactor with a copper rod inner electrode and compared with a plasma-catalytic reactor. The particularity of the plasma-catalytic reactor is the inner electrode made of sintered metal fibers (SMF) coated by transition metal oxides. In order to optimize the geometry of the plasma reactor, the efficiency of TCE removal was compared for different discharge gap lengths in the range of 1-5 mm. Shorter gap lengths (1-3 mm) appear to be more advantageous with respect to TCE conversion. In this case TCE conversion varies between 67% and 100% for input energy densities in the range of 80-480 J/l, while for the 5 mm discharge gap the conversion was lower (53-97%) for similar values of the input energy. As a result of TCE oxidation carbon monoxide and carbon dioxide were detected in the effluent gas. Their selectivity was rather low, in the range 14-24% for CO 2 and 11-23% for CO, and was not influenced by the gap length. Several other chlorinated organic compounds were detected as reaction products.When using MnOx/SMF catalysts as the inner electrode of the DBD reactor, the TCE conversion was significantly enhanced, reaching $95% at 150 J/l input energy. The selectivity to CO 2 showed a major increase as compared to the case without catalysts, reaching 58% for input energies above 550 J/l. #

Non-thermal plasma abatement of trichloroethylene with DC corona discharges

“…The by-product analysis indicates that TCE is only partially mineralized. This demonstrates one of the shortcomings of NTP which can be improved by catalyst hybridization [14][15][16]. Figure 3 shows the effect of the initial TCE concentration on the RE for both negative and positive corona.…”

Volatile organic compounds decomposition using nonthermal plasma coupled with a combination of catalysts

“…Control of VOCs in the atmosphere is a major environmental problem now and attracts more and more researchers' attentions (Futamura et al, 1997;Muhamad et al, 2000;Gal et al, 2003;Magureanu et al, 2005;Malik et al, 2005;Kim, 2006;Magureanu et al, 2007;Juang et al, 2009a;Zhu et al, 2009a). As one of the typical VOCs, toluene effluents came from many industries, including paints, paint thinners, fingernail polish, lacquers, adhesives, rubber and some print and leather tanning processes.…”

Decomposition of benzene by non-thermal plasma processing: Photocatalyst and ozone effect

“…In particular, non-thermal plasma has attracted much attention as an method for VOCs control for two decades due to its unique properties such as quick response at ambient temperature, achievement of high electron energies within short residence times, system compactness, and easy operations (Muhamad, 2000;Li et al, 2006). In order to improve the energy efficiency of the VOCs decomposition process by the plasma, the cooperation with catalyst has been tested by some researchers (Einaga et al, 2001;Guo et al, 2006;Jim, 2008;Krawczyk, 2001;Magureanu et al, 2007a and b;Ogata et al, 2003;Wallis et al, 2007;Li et al, 2007;Zhu et al, 2007b). These studies showed that the combination of discharge plasma with catalyst is a very effective method in VOCs removal.…”