Relationship between dynamic change of copper and dioxin generation in various fly ash

Takaoka, Masaki; Shiono, Atsuhiro; Yamamoto, Takashi; Uruga, Tomoya; Takeda, Nobuo; Tanaka, Tsunehiro; Oshita, Kazuyuki; Matsumoto, Tadao; Harada, Hidenori

doi:10.1016/j.chemosphere.2007.06.093

Cited by 14 publications

(16 citation statements)

References 18 publications

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“…This tendency was consistent with our previous results, and modification of activated carbon with HNO 3 solution was thought to contribute to the stable condition of the free radicals (Takaoka et al, 2008 ) and g value (2.0078) of H 2 SO 4 -AC were higher than those of N 2 -AC. Yabuta et al (2008) suggested that the free radical content (i.e., N s ) was positively related to the amount of carboxyl (-COOH) functional groups following an analyses of various humic substances using ESR and solid-state 13 C nuclear magnetic resonance.…”

Section: Surface Area Free Radical and Functional Groups Of Macromosupporting

confidence: 93%

“…Compared with N 2 -AC, the activated carbon modified by the HNO 3 solution (HNO 3 -AC) had a smaller surface area (918 m 2 /g). This feature of HNO 3 -AC might be derived from the destruction of mesoand micropores by oxidation (Takaoka et al, 2008). A similar decrease in surface area was noted following the H 2 O 2 treatment (H 2 O 2 -AC).…”

Section: Surface Area Free Radical and Functional Groups Of Macromosupporting

confidence: 55%

“…The concentration of PCDDs (Cl 4 -Cl 8 homologs) and PCDFs (Cl 4 -Cl 8 ) in model fly ashes was analyzed by highresolution GC/high-resolution MS (HRGC/HRMS) as performed in our previous study (Takaoka et al, 2008). PCBs (Cl 2 -Cl 8 ) and CBzs (Cl 2 -Cl 6 ) were analyzed by HRGC/low-resolution MS (models: HP-6890/HP-5973; Hewlett-Packard).…”

Section: Quantification Of Pcdds Pcdfs Pcbs and Cbzsmentioning

confidence: 99%

“…Our previous study using the same activated carbon reported numerous pores of ca. 10 µm in diameter on the surface of the activated carbon (Takaoka et al, 2008). Compared with N 2 -AC, the activated carbon modified by the HNO 3 solution (HNO 3 -AC) had a smaller surface area (918 m 2 /g).…”

Section: Surface Area Free Radical and Functional Groups Of Macromomentioning

confidence: 99%

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Influence of the Properties of Macromolecular Carbon on de Novo Synthesis of PCDDs, PCDFs, PCBs, and Chlorobenzenes

Fujimori

Nishimura

Oshita

et al. 2014

Aerosol Air Qual. Res.

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We examined the influence of the properties of macromolecular carbon on thermochemical de novo synthesis of toxic chlorinated aromatic compounds (aromatic-Cls), such as polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs), biphenyls (PCBs), and chlorobenzenes (CBzs). Six types of macromolecular carbons were prepared. Some activated carbon samples were modified by chemical solvents, such as nitric acid, hydrogen peroxide, sulfuric acid, and urea solutions, to change the properties of the activated carbon. We characterized six macromolecular carbons by surface area (8.8-1540 m 2 /g), free radicals (N s = not analyzed to 67.0 × 10 19 g -1 , g = 2.0011-2.0098), and functional groups (O-H, C-H, C=O, C=C, C-O, and C-OH). Concentrations of aromatic-Cls at 300-400°C, such as PCDDs, PCDFs, PCBs, and CBzs, were clearly influenced by the type of macromolecular carbon. Their distribution between the ash/gas phases implied that increasing the surface area mainly enhanced the adsorption capacity of macromolecular carbon, while increasing the number of free radicals mainly enhance the reaction activity of macromolecular carbon. The PCDD/PCDF ratio suggested that various modifications of macromolecular carbon contributed to the generation of PCDDs in addition to the catalytic behavior of copper. Under most conditions, the surface area of macromolecular carbon did not have a strong correlation with the generation of PCDDs, PCBs, and CBzs, but it did show have a correlation with the generation of PCDFs. One of the destructive effects of aromatic-Cls resulted from the free radicals in macromolecular carbon. The C=O bond (ca. 1720 cm -1 ) functional group in macromolecular carbon had no strong correlation with the generation of aromatic-Cls, because free radicals had a destructive effect. The functionalities of ether (C-O) or phenolic OH (C-OH) in macromolecular carbon were causative factors in the generation of oxygen-containing aromatic-Cls, such as PCDDs and PCDFs.

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Section: Surface Area Free Radical and Functional Groups Of Macromosupporting

confidence: 93%

Section: Surface Area Free Radical and Functional Groups Of Macromosupporting

confidence: 55%

Section: Quantification Of Pcdds Pcdfs Pcbs and Cbzsmentioning

confidence: 99%

Section: Surface Area Free Radical and Functional Groups Of Macromomentioning

confidence: 99%

See 2 more Smart Citations

Influence of the Properties of Macromolecular Carbon on de Novo Synthesis of PCDDs, PCDFs, PCBs, and Chlorobenzenes

Fujimori

Nishimura

Oshita

et al. 2014

Aerosol Air Qual. Res.

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“…We previously confirmed there was no significant difference in the formation of dioxins or distribution patterns of PCDDs and PCDFs between BN and SiO2. 11 KCl was not mixed in these model fly ashes, because the Cl K-edge NEXAFS spectrum of inorganic chloride in real fly ash hardly changed, and we wanted to examine only the behavior of chlorine with the metal. We also measured these model fly ashes that were heated at 300 and 400 C and then immediately sealed.…”

Section: K-edge Nexafsmentioning

confidence: 99%

Chlorination Mechanism of Carbon during Dioxin Formation Using Cl-K Near-edge X-ray-absorption Fine Structure

et al. 2010

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Many environmental organic chemicals have chloride in their structure. Thus, researching the chlorination mechanism of carbon is of interest. Dioxins are typically concentrated in fly ash collected from the post-combustion zone during the operation of municipal solid waste incinerators. In this study, we report the application of Cl-K near-edge X-rayabsorption fine structure (NEXAFS) in determining the chlorination mechanism of carbon in fly ash. The separation of a chloride-carbon (C-Cl) bond was readily recognizable as a peak in the Cl-K NEXAFS spectrum. Chlorination effects could be estimated using Cl K-edge NEXAFS with no dependence on metal species. Analysis of Cl K-edge NEXAFS spectra showed the reduction of copper(II) chloride at 300 C and oxidation of iron(III) chloride at 400 C in connection with the chlorination of carbon.

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Distribution of remaining Cd in MSWI fly ash washed with nitric acid

Zhao

Wang

et al. 2016

J Mater Cycles Waste Manag

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Relationship between dynamic change of copper and dioxin generation in various fly ash

Cited by 14 publications

References 18 publications

Influence of the Properties of Macromolecular Carbon on de Novo Synthesis of PCDDs, PCDFs, PCBs, and Chlorobenzenes

Influence of the Properties of Macromolecular Carbon on de Novo Synthesis of PCDDs, PCDFs, PCBs, and Chlorobenzenes

Chlorination Mechanism of Carbon during Dioxin Formation Using Cl-K Near-edge X-ray-absorption Fine Structure

Distribution of remaining Cd in MSWI fly ash washed with nitric acid

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