Enhancement of Flue Gas Low-Concentration Toluene Removal in Pulsed Plasma Coupling with Porous Ceramic Modified Catalyst Reactor

A novel coaxial pulsed plasma coupling with porous ceramic tube modified by Co/Mn oxide catalyst reactor was used to remove low-concentration toluene from the flue gas. The pulsed plasma coupling with catalyst (PPCC) reactor was designed according to actual process conditions, including temperature, initial concentration, residence time, and so on. The PPCC reactor was used for the generation of plasma and consisted of a porous ceramic membrane tube (CMT) with catalyst pressed on the inner wall and an electrode at the center. The simulated flue gas flowed into the PPCC reactor according to in-plasma catalysis (IPC) or postplasma catalysis (PPC) models. At concentrations lower than 100 ppm, the PPCC reactor mainly decomposed toluene to CO2 and CO. The Co1Mn0.11-CMT (Co/Mn = 1:0.11) catalyst showed the best degradation efficiency of 97.7% and CO2 selectivity of 93.8% with a specific energy density of approximately 800 J/L by the PPC model. The byproduct O3 was also detected and discussed. Finally, the related reaction mechanism was explained by DFT calculations. This study guides engineering application of PPCC technology.