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Polychlorinated dibenzofurans (PCDFs) and polychlorinated naphthalenes (PCNs) are known to be emitted from municipal waste incinerators (MWIs) with polychlorinated dibenzo-p-dioxins (PCDDs). Two formation paths for PCDD/ Fs could mainly work, which are condensation of the precursors such as chlorophenols and "de novo" formation from carbon. However the correlation between the chemical structure of carbon and the resulting PCDD/Fs still remains unknown. In this study, the PCDD/Fs formation from polycyclic aromatic hydrocarbons (PAHs) and CuCl was examined at 400 under 10% O 2 . Coronene among the PAHs characteristically gave 1,2,8,9-T4CDF and the derivatives. These isomers clearly indicate that chlorination causes the cleavage of the C-C bonds in a coronene molecule and also that oxygen is easily incorporated from its outside to form 1,2,8,9-T4CDF. The symmetrical preformed structures in the coronene molecule enabled to amplify the de novo formation of the isomer. PCNs are also formed directly from these PAHs. Since there have been few reports on the formation mechanism of PCNs, this study will be a first step to know the whole formation paths. We also define the de novo synthesis as the breakdown reaction of a carbon matrix, since the word has been used without the precise definition.

Strong and high purity O− negative ion emission has been observed from a synthesized crystal 12CaO⋅7Al2O3 surface. A μA/cm2-level O− emission from this material has been achieved at the surface temperature of 800 °C and the extraction field over 1000 V/cm, which is about three orders of magnitude higher than the current density emitted from the Y2O3-stabilized ZrO2 electrolyte surface. The strong emissivity of this material, as well as easy and economical fabrication, may provide a useful tool to generate the O− negative ion, which is expected to be one of the most important radicals for chemical syntheses and material modifications.

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A dry-desulfurization process using Ca(OH)2/fly ash sorbent and a circulating fluidized bed (CFB) was developed. Its aim was to achieve high SO2 removal efficiency without humidification and production of CaSO4 as the main byproduct. The CaSO4 produced could be used to treat alkalized soil. An 83% SO2 removal rate was demonstrated, and a byproduct with a high CaSO4 content was produced through baghouse ash. These results indicated that this process could remove SO2 in flue gas with a high efficiency under dry conditions and simultaneously produce soil amendment. It was shown that NO and NO2 enhanced the SO2 removal rate markedly and that NO2 increased the amount of CaSO4 in the final product more than NO. These results confirmed that the significant effects of NO and NO2 on the SO2 removal rate were due to chain reactions that occurred under favorable conditions. The amount of baghouse ash produced increased as the reaction progressed, indicating that discharge of unreacted Ca(OH)2 from the reactor was suppressed. Hence, unreacted Ca(OH)2 had a long residence time in the CFB, resulting in a high SO2 removal rate. It was also found that 350 degrees C is the optimum reaction temperature for dry desulfurization in the range tested (320-380 degrees C).

A novel approach to the direct synthesis of phenol from benzene was obtained with high benzene conversion (30%) and phenol selectivity (approximately 90%) by using a microporous material [Ca24Al28O64]4+.4O-(C12A7-O-) as catalyst with oxygen and water; active O- and OH- anions are proposed to play important roles in the formation of phenol by hydroxylating the aromatic ring of benzene.