Plasma Chemistry and Plasma Processing, Vol.39, No.1, 125-142, 2019
Removal of Toluene from Air Using a Cycled Storage-Discharge (CSD) Plasma Catalytic Process
Cycled storage-discharge (CSD) air-plasma catalytic process was used for removing toluene from simulated 40% humid air. The different catalytic activities of HZSM-5 and Ag/HZSM-5 catalysts were entered in a dielectric barrier discharge reactor in two-layer form. The experiments were conducted with different filling layout of HZSM-5 and Ag/HZSM5. It is found that the catalysts filling layout, wt% of Ag load on the Ag/HZSM5 layer, the amount of stored toluene at the storage phase, and the discharge gas flow rate were the main factors that could affect the performance of plasma catalytic oxidation of the stored toluene. The performance was maximized when the catalyst-filling layout was 0.5g HZSM5, followed 0.5g 5.2wt% g/HZSM5, and the discharge air flow rate was 1l/min. When the stored toluene in the storage phase was 77% of toluene adsorbing breakthrough capacity of the first layer catalyst, close to 100% of the stored toluene was oxidized, and so the carbon balance and the CO2 selectivity reached to 100% with no significant O-3 and NOx observed in the outlet. By optimizing the storage and discharge period and discharge gas flow, the electrical energy yield and the performance of toluene oxidation were maximized and the energy consumption was minimized. [GRAPHICS]
Keywords:Plasma catalysis;Toluene removal;Ag;HZSM-5 catalyst;Dielectric barrier discharge (DBD);Cycled storage-discharge (CSD)