title: [Photocatalytic degradation of 1,2, 4-trichlorobenzene with TiO2 coated on carbon nanotubes].
abstract: Effects and kinetics of photocatalytic degradation of 1,2,4-trichlorobenzene with composite photocatalysts of TiO2 coated on carbon nanotubes and nano-TiO2 photocatalysts were studied, respectively. It was found that the composite photocatalysts was better than the nano-TiO2 for photocatalytic degradation of 1,2,4-trichlorobenzene. After 60 min UV irradiation at 254 nm, there was 70% of the initial 1,2,4-trichlorobenzene degraded with the composite photocatalyst while only 51% of the initial 1,2,4-trichlorobenzene degraded with the nano-TiO2. Results of photocatalytic degradation kinetics also proved that the 1,2,4-trichlorobenzene degradation rate constant with the composite photocatalyst was 0.019 6 h(-1), which was increased by 63.3% compared to that with nano-TiO2. According to molecular structure theory, analysis of dissociation energy of C--Cl bond of chlorobenzenes predicated that main pathway of photocatalytic degradation of 1,2,4-trichlorobenzene followed that its ortho-Cl could be took off first to form 1, 4-dichlorobenzene, and it might be further dechlorized and finally be mineralized. The first step of photodechlorination for 1,2,4-trichlorobenzene was also experimentally confirmed through identified 1,4-dichlorobenzene as its product.
authors.affiliation: College of Civil Engineering, Hunan University, Changsha 410082, China. hnweizhang@163.com
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Shi
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hu
authors.initials: H
authors.lastname: Zhang
authors.forename: Shun-Kai
authors.initials: SK
authors.lastname: Xu
mesh_terms: D002384:Catalysis; D002722:Chlorobenzenes / Q000737:chemistry / Q000302:isolation & purification*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D007700:Kinetics; D037742:Nanotubes, Carbon / Q000737:chemistry*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*
chemical_list: D002722:Chlorobenzenes; D020099:Coated Materials, Biocompatible; D004785:Environmental Pollutants; D037742:Nanotubes, Carbon; C009947:1,2,4-trichlorobenzene; C009495:titanium dioxide; D014025:Titanium