title: Low temperature destruction of PCDD/Fs by catalysis coupled with activated carbon.
abstract: In order to enhance the oxidation and adsorption capacity of catalyst, two kinds of activated carbon (AC) are mechanically mixed with V2O5-WO3/TiO2 catalyst respectively. In this study, the mixtures (M-1: catalyst mixing with AC based on lignite; M-2: the one on coconut shell) are investigated to destroy high concentration (9.8 ng I-TEQ Nm(-3)) PCDD/Fs at low temperature (160 °C). Adding AC into the catalyst obviously increases removal efficiency (RE) and destruction efficiency (DE). However, M-2 presents higher RE value and lower DE value compared with M-1 at the same conditions as the stronger adsorption capacity of AC based on coconut shell. For the M-2 mixture, RE values are decreasing while DE values show an opposite trend with the ratios of catalyst to AC increasing. Oxygen plays a positive role on the destruction of PCDD/Fs by accelerating the conversion of V(4+)Ox and V(5+)Ox. Adjusting oxygen content from 0 to 20 % could increase the DE value from 27.4 to 82.2 % for the M-1 and from 15.8 to 68.9 % for the M-2. In the presence of ozone, a dark brown flock will be generated when the ratio of AC and catalyst is 4:1 due to the reaction between AC and ozone, which results in the lower RE and DE values. The RE and DE values reach the maximum of 96.3 %, 90.6 % in this paper, respectively, when the ratio of AC and catalyst is 1:1 with ozone. Finally, the regenerating of mixture is investigated. Most of dioxin residues in the mixture are desorbed and oxidized by catalysis at 200 °C in the presence of oxygen.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, Hangzhou, 310027, China.
authors.forename: Ming-Feng
authors.initials: MF
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, Hangzhou, 310027, China. lixd@zju.edu.cn.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Li
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, Hangzhou, 310027, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, Hangzhou, 310027, China.
authors.forename: Sheng-Yong
authors.initials: SY
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, Hangzhou, 310027, China.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Yan
mesh_terms: D000327:Adsorption; D001572:Benzofurans / Q000737:chemistry*; D002384:Catalysis; D002606:Charcoal / Q000737:chemistry*; D003080:Cold Temperature; D004147:Dioxins / Q000737:chemistry; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry; D000072317:Polychlorinated Dibenzodioxins / Q000737:chemistry*; D013696:Temperature
chemical_list: D001572:Benzofurans; D004147:Dioxins; D000072317:Polychlorinated Dibenzodioxins; D002606:Charcoal; D010126:Ozone
keywords: Activated carbon; Catalysis; Oxygen; Ozone; PCDD/Fs; Regenerating