title: [Degradation of PCDD/Fs by the Mixture of V2O5-WO3/TiO2 Catalyst and Activated Carbon].
abstract: The mixture of V2O5-WO3/TiO2 catalyst and two kinds of Activated Carbons (AC) (AC-1: based on lignite; AC-2: based on coconut shell) was used to destroy gas phase PCDD/Fs with high concentration (9. 80 ng.m-3, evaluated by international toxic equivalence quantity (I-TEQ) under low thermal temperature (160°C) based on a dioxin generating system. After mixing with AC, removal efficiency (RE) and destruction efficiency (DE) of PCDD/Fs increased by 20% compared with only catalyst condition. In comparison with mixture of AC based on coconut shell, mixture of AC based on lignite had lower RE-values and higher DE-values. The adjustments of the ratio of catalyst and AC could cause the different degradation effects, and RE-values increased and DE-values decreased with increasing proportions of catalyst. When the volume fraction of oxygen was 0% in experimental atmosphere, catalyst could lose its activity and most PCDD/Fs were not oxidized but adsorbed by the mixture. RE and DE-values increased with increasing content of oxygen. The addition of ozone (concentration of 200 mg.m-3) could improve catalytic oxidation effects to a certain degree. However, ozone might react with AC, which could influence the lifetime of the mixture. Under 200°C, the mixture with proportion of AC: catalyst = 1:1 and in the present of 200 mg.m-3 ozone conditions, the highest RE and DE-value were obtained with 98. 0% and 94. 8% respectively, and the concentration of PCDD/Fs residual in off-gas was only 0. 51 ng.m-3 evaluated by I-TEQ.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ren
authors.forename: Sha-sha
authors.initials: SS
authors.lastname: Ji
authors.forename: Ming-feng
authors.initials: MF
authors.lastname: Yu
authors.forename: Xiao-dong
authors.initials: XD
authors.lastname: Li
authors.forename: Jian-hua
authors.initials: JH
authors.lastname: Yan
mesh_terms: D000327:Adsorption; D001572:Benzofurans / Q000737:chemistry*; D002384:Catalysis; D002606:Charcoal / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D010126:Ozone; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014414:Tungsten / Q000737:chemistry*; D017968:Vanadium Compounds / Q000737:chemistry*
chemical_list: D001572:Benzofurans; D010087:Oxides; D000072317:Polychlorinated Dibenzodioxins; D011108:Polymers; D017968:Vanadium Compounds; C016068:polychlorodibenzofuran; C009495:titanium dioxide; D002606:Charcoal; D010126:Ozone; C511604:tungsten oxide; C066075:vanadium pentoxide; D014025:Titanium; D014414:Tungsten