Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society on Water Environment  

<p>There are some reports that transformation products of a pesticide exist at higher concentrations than their parent pesticide, or their pharmacological activities are comparable to that of a parent pesticide. It is therefore of importance to examine their potential effects on aquatic organisms; however, few studies have focused on the insecticidal activities of a transformation product of dinotefuran, a neonicotinoid pesticide. In this study, dinotefuran's transformation products were explored by LC-HRMS analyses of dinotefuran aqueous solutions that had been irradiated by a xenon lamp. This exploration resulted in the discovery of two unknown transformation products. Structural elucidations of these two compounds suggested 28 and 82 chemical structures in terms of structural isomers and steric isomers, respectively. Their binding affinities for a glia-derived acetylcholine-binding protein of <i>Lymnaea</i> <i>stagnalis</i> were simulated to estimate their insecticidal activities. Out of 28 candidates, 20 were judged to have significant insecticidal activities. It can be concluded that the simulation of a substance's binding affinity, the so-called docking simulation, is a promising way to exclude nontoxic substances among a large number of candidate substances.</p>

DOI： 10.2965/jswe.43.1

CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOCIETY OF ENVIRONMENTAL SCIENCE, JAPAN  

<p>2,4-Dinitrophenylhydrazine (DNPH) is one of the most common derivatizing reagent used for an analysis of aldehydes or ketones. Derivatives produced by this reaction are readily detected by UV/Vis photospectrometer or LC/MS. However, during the derivatization, an excess amount of DNPH is added to a sample and a large part of it remains unreacted. Injecting this residual DNPH into an analytical instrument may lead to some negative effects such as a damaged LC column, or a clogged sampling cone, probably resulting in an impaired detection sensitivity. It is therefore of importance to remove unreacted DNPH prior to an analysis.</p><p>The objective of this study is to develop a purification method for a DNPH-derivatized sample. Solid phase extraction (SPE) was focused on as a strategy to achieve this. The SPE purification method developed in this study removed 97.5％ of unreacted DNPH and recovered 103％ of a derivative. Additionally, quantum chemistry calculation was adopted to verify the experimental results. The calculation results were in good accordance with the experimental ones, <i>i.e.</i>, the complexation between DNPH and a sorbent was more stable than that between a derivative and a sorbent.</p>

DOI： 10.11353/sesj.33.70

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)  

© 2019 Japan Society on Water Environment. From three different sewage treatment plants, three effluent samples were collected to demonstrate applicability of a non-targeted mass spectrometric analysis for exploration and identification of organic ecotoxicants in the samples. Five known organic ecotoxicants were added to these samples to simulate toxic samples. The non-targeted analyses of the simulated samples were conducted with a liquid chromatograph-high resolution mass spectrometer. The whole effluent toxicity tests were conducted by using Raphidocelis subcapitata as the test organism. The number of components detected by the analyses was 3,427. Relationships between peak volumes of these detected components and the samples' toxicities were analyzed by the orthogonal projections to latent structure-regression analysis, the correlation analysis and the multiple regression analysis. An ion of m/z 286.9436 was found as a possible monoisotopic ion of the added toxicant. A molecular formula of the ion was determined by its accurate mass and natural isotopic pattern. The determined molecular formula was searched in an advanced mass spectral database. The database suggested that the found toxicant is triclosan (an antibacterial and antifungal agent). It was identified as triclosan by a co-chromatography using a reference standard reagent. Because a dominant toxicant was triclosan among the added five toxicants, the applicability was successfully demonstrated.

DOI： 10.2965/jwet.18-083

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

© 2018 Elsevier Ltd The estimated domestic usage of DD (a typical nematocide) has been the greatest among all the agricultural chemicals in Japan. DD is involved in a document which is used to establish tap water quality standard in Japan. The document indicates that DD is potentially detectable in raw water for tap waters. DD in raw water will be treated with chlorine at waterworks, which raises concerns about formation of mutagenic chlorination by-products through the treatment. The objective of this work was to identify a mutagenic chlorination by-product by using high resolution mass spectrometers and multivariate analyses. Mutagenicity of the chlorination by-product was evaluated with the Ames Salmonella mutagenicity assay. (E)-1,3-Dichloropropene (DCP) was used as a model compound of DD. The mutagenicity of chlorine treated model aqueous solutions of DD increased with increasing chlorine dosages up to 3.00 mol-Cl2/mol-DCP. From the chlorine treated aqueous solutions of DD, 1,3-dichloroacetone (DCA) was identified as a major mutagen by a cochromatography with an authentic standard, precursor ion analyses and first-generation product ion analyses with the high resolution mass spectrometers. The mutagenicity of DCA against TA100 strain without microsomal activation was 160,000 net revertant colony/μmol (the toxicity equivalent factor was 0.14). Based on the mutagenicity of the chlorine treated DCP sample, the specific mutagenicity of DCA, and the DCA concentration in the sample, the mutagenic contribution of DCA to the chlorine treated DCP sample was calculated. High contribution (98%) clearly shows that DCA is a major mutagen in the chlorine treated DCP sample. Because the exploration of DCA was performed by using the unrealistic high concentration samples of DCP and chlorine, formation of DCA in the practical concentration samples (0-200 μg-DCP/L, 0.10 or 1.27 mg-Cl2/L) was examined. It was proven that DCA formation reaction takes place in the practical concentrations of DCA and chlorine.

DOI： 10.1016/j.watres.2018.09.024

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

© 2017 Elsevier B.V. Five kinds of coals (mainly low Se levels) were pulverized and combusted in a turbulent furnace combustion test rig, which had a burner on the top and a gas cooling pipe with two sampling ports at the side near the bottom. A sampling train according to ISO 17211:2015 was attached to the ports to assess the distribution of Se in the gas and solid phase (coal ash) in the flue gas. The fraction of Se in the solid phase (R Ses) in the flue gas is given by R Ses = Ses/(Ses + Seg), where Ses and Seg are the concentrations of Se in the solid and gas phases, respectively. For all coals, R Ses increased with a decrease in the flue gas temperature from 300 °C to 100 °C, and the difference in R Ses by the temperature was greatly dependent on the kinds of feed coals. The effects of the contents of minerals in feed coals and the combustion conditions upon R Ses were studied. The partitioning of Se from the gas to solid phase in the flue gas was elucidated in terms of the chemical and physical adsorption of Se on coal ash.

DOI： 10.1016/j.fuproc.2017.07.019

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.11353/sesj.29.229

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

© 2016 Taylor & Francis. Mt. Sakurajima is a volcanic island in Japan, and a big city, Kagoshima, is quite close to the active volcano. Samples of volcanic ash fall erupted from Mt. Sakurajima were collected at several locations in Kagoshima City and analyzed for Hg and other elements, including major (Mg, Al, Ca, and Fe) and trace elements (V, Cr, Mn, Co, Ni, Zn, As, and Pb). The concentrations of Hg varied from 6.3 to 124 ng g−1, with the amounts of ash varying from 13 to 1230 g m−2 month−1. The Hg concentrations tended to be higher when the monthly amounts of ash fall were lower; other elements did not show such a tendency.

DOI： 10.1080/02772248.2016.1139117

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

© 2015 Elsevier B.V. By using subcritical water (SW), a simple method of the recovery of selenium (Se) from food samples was developed for the determination of Se by inductively coupled plasma mass spectrometry (ICP-MS). A portion of powdery dried sample was precisely weighed and mixed with pure water (liquid/solid ratio, 100). This was placed in a sealed vessel, and heated in an electric oven. The resulting aqueous phase was analyzed for Se by ICP-MS. The optimum conditions for the recovery of Se were studied by using certified reference materials of biological samples (NMIJ-7402a and TORT-2). In order to validate the SW treatment as an analytical pretreatment, fourteen food samples under the optimum conditions (treatment temperature, 220. °C; time 120. min) were tested. The samples include fishes, shellfishes, meats, and dried seaweeds. The Se concentrations obtained using the SW treatment were about the same as those with the conventional method, microwave-assisted acid digestion. The dissolution behavior of Se during the SW treatment was clearly elucidated by using water extraction and SEC-ICP-MS analysis.

DOI： 10.1016/j.microc.2015.10.012

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Institutional Repository URL

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Fifty-one kinds of coals, which are practically used in Japanese power plants and industries, were analyzed for Hg by an automatic mercury analyzer (AMA) based on an official method (heat vaporization atomic absorption spectrometry). Almost all coals were imported coals from various countries. These coals are supplied in a powdery form as standard samples by a Japanese organization and called "SS-coals". Since the sample amount of coal used in the AMA measurement is usually small, the particle size of coal may greatly affect the measurement, however there have been no systematic studies on the matter. Some of the SS-coals, which were much finer than frequently-used certified reference materials (NIST SRM coals), showed a great deviation in data (relative standard deviation (RSD) is high) in the determination of Hg. The SS-coals were ground further into fine powder, and the resulting coals (ground SS-coals) gave lower RSD values. The mean values of Hg content when the as-received SS-coals were measured many times (more than six runs) became about the same as those for the ground SS-coals. The deviation in data in the Hg determination was discussed with the possibility of localization of Hg in coal body at a microscopic level. The content of Hg in coal (bituminous coals) correlated not with that of sulfur (or pyritic sulfur) but with that of ash. Also, it was found that the coals of high inherent moisture exclusively had low Hg contents. © 2013.

DOI： 10.1016/j.microc.2013.12.012

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Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.2965/jwet.2013.419

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society on Water Environment  

There have been many reports regarding the concentrations of pesticides in environmental waters. In contrast, only a few studies of pesticide transformation products in water environments (PTPWs) could be found in the literature, which can be attributed to the lack of an established PTPW list. Pesticides sprayed in water environments are quickly degraded, producing PTPWs such as hydrolysates and oxidative degradation products. These PTPWs remain in surface water, and are then chlorinated in waterworks. Thus, monitoring PTPW concentrations in environmental waters, and studying PTPW removal in waterworks are important in order to provide chemically safe tap water. Thus, in the present study, a PTPW list consisting of 610 PTPWs of 145 pesticides reported in the Evaluation Reports published by the Pesticides Expert Committee, Food Safety Commission, and 73 PTPWs of 14 pesticides found by reviewing 12,269 scientific papers was compiled in order to promote monitoring studies of PTPWs in environmental waters and PTPW removal in waterworks.

DOI： 10.2965/jswe.36.29

CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Japan Society for Analytical Chemistry  

The combination of HPLC, oxidative decomposition by UV irradiation, and cold vapor atomic fluorescence spectrometry (HPLC-UV-CVAFS) was applied to the fractional determination of mercury species, which were contained in biological samples, such as seafood. Firstly, the extraction of mercury species from biological samples was studied, and it was found that 2-mercaptoethanol (2-ME), which has a mercapto group, was an effective extractant. For three certified reference materials, which have the certified values of the CH₃Hg⁺ concentration, extraction by a 2-ME solution and the HPLC-UV-CVAFS measurement were carried out. It was confirmed that the measured values were about the same as the certified values. The same analytical method was applied to real seafood samples. The sum of the CH₃Hg⁺ concentration and the Hg²⁺ concentration in the extraction solution, which was obtained by the HPLC-UV-CVAFS measurement, was about the same as the total mercury concentration obtained by the heat vaporization atomic absorption spectrometry (HVAAS) measurement. Therefore, it is evident that the fractional determination of mercury species in biological samples was favorably performed when the extraction solution obtained by the 2-ME extraction was analyzed by HPLC-UV-CVAFS.

DOI： 10.2116/bunsekikagaku.61.1073

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Other Link： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2012&ichushi_jid=J01343&link_issn=&doc_id=20121211470002&doc_link_id=10.2116%2Fbunsekikagaku.61.1073&url=https%3A%2F%2Fdoi.org%2F10.2116%2Fbunsekikagaku.61.1073&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_3.gif

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.2965/jwet.2012.437

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2965/jwet.2012.375

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IWA PUBLISHING  

A new method for the removal of arsenite [As(III)] and selenate [Se(VI)], which are difficult to remove by conventional water treatment methods from aqueous media, was investigated. This method involves the use of photocatalytic oxidation of As(III) and photocatalytic reduction of Se(VI). Also, a novel TiO2-adsorbent hybrid (HYB) which has photocatalyst sites and adsorbent sites on the same particle was developed. When the removal of As(III) by use of photocatalyst-adsorbent system and the HYB system was carried out, As(III) was effectively removed from aqueous phase. Moreover, with the removal of Se(VI) by using photocatalytic reduction, Se(VI) could also be removed from aqueous phase under the photocatalyst-adsorbent system and the HYB system, even if the concentration of a hole scavenger formic acid was reduced. © IWA Publishing 2012.

DOI： 10.2166/ws.2011.090

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A detailed analysis was performed on the slurry supernatant water obtained from a wet flue gas desulfurization (FGD) system in a pilot plant of a coal combustion facility using five different coals. The determination of trace elements in those samples was performed by use of inductively coupled plasma-atomic emission spectrometry (ICP-AES), inductively coupled plasma-mass spectrometry (ICP-MS), and other methods, while the analysis of major cations and anions was conducted by ICP-AES and ion chromatography, respectively. The levels of B, Se, and Hg in the FGD water were sometimes high (44-62 mg/L for B, 0.24-0.37 mg/L for Se, and 0.11-0.23 mg/L for Hg), and these values exceeded the Japanese national effluent standards for terrestrial water (10, 0.1, and 0.005 mg/L for B, Se, and Hg, respectively). Simulated FGD water was prepared as a result of the analysis mentioned above, and the removal of those hazardous elements was attempted using various adsorbents, including N-methylglucamine resins (DIAION CRB02 and CRB05), a N-methylglucamine fiber (Chelest fiber GRY-L), an iminodiacetic acid resin (DIAION CR11), a polyamine resin (DIAION CR20), an anion-exchange resin (DOWEX 1X8), activated alumina, and activated carbon. For the simultaneous removal of B and Hg from the simulated FGD water, which contained 60 mg/L of B and 0.11 mg/L of Hg, CRB02 was the most effective and the percent removal values for B and Hg were 88 and 97%, respectively. The resulting water met the effluent standards. © 2011 American Chemical Society.

DOI： 10.1021/ef200377r

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Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A relative comparison study of mutagenicity in Japanese tap water was conducted for 1993 and 2005 surveys. It intended to assess the effects of advanced water treatment installations to water works, improvement of raw water quality and improvement of residual HOCl concentration controlling. Sampling points (taps) were the same in both surveys. The results of 245 samples obtained by the Ames Salmonella mutagenicity test (Ames test) were analyzed. The Ames tests were conducted by using Salmonella typhimurium TA98 and TA100 strains with and without exogenous activation (S9). With the exception of TA100-S9, the other conditions needed no discussion as a factor in the mutagenicity level change. The average mutagenicity in 1993 and 2005 under the conditions of TA100-S9 were 2600 and 1100 net revertantL-1, respectively. This indicated that the mutagenicity level of Japanese tap water decreased during the 12-yr period. Particularly a remarkable decrease in mutagenicity was observed in the water works where the advanced water treatments were installed during the 12-yr period. The advanced water treatments were effective in decreasing the mutagenicity of tap water. Mutagenicity also decreased in the water works with conventional water treatments; the improvement of residual HOCl concentration controlling was also considered to be effective in decreasing the mutagenicity of tap water. © 2011 Elsevier Ltd.

DOI： 10.1016/j.chemosphere.2011.03.047

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2965/jwet.2011.13

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER  

For the arsenic speciation in marine product samples, two types of pretreatment-analysis combination were compared. One is the combination of solvent extraction and high performance liquid chromatography (HPLC) followed by a highly sensitive arsenic detection, while the other is the combination of alkaline digestion and cryogenic trap (CT) method followed by a highly sensitive arsenic detection. For six certified reference materials (CRMs) of marine animal samples, the concentrations of arsenobetaine (AsB) obtained from the extraction-HPLC method were very consistent with those of trimethylated arsenic species measured by the digestion-CT method. For four seaweed samples, the determination of three arsenosugars (Sugar-1, Sugar-2, and Sugar-3) was favorably carried out by the extraction-HPLC method. Those seaweed samples were also subjected to the digestion-CT method, and the amounts of dimethylated arsenic species measured by the method were approximately equal to the sum of the amounts of dimethylarsinic acid (DMAA) and three arsenosugars (Sugar-1 + Sugar-2 + Sugar-3) obtained from the extraction-HPLC method. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.talanta.2009.03.067

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Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

By use of oxygen flask combustion (OFC), a rapid and convenient determination method for mercury (Hg) and sulfur (S) in coal was developed. For the determination of Hg in coal, the OFC method with a KMnO4 solution as an absorbent was carried out, and the resulting solution was analyzed by cold vapor atomic fluorescence spectrometry (CVAFS). For six certified reference material coals, the Hg concentrations obtained by this method were in good accordance with the certified or reference values. In addition, nine brands of Japanese standard coals (SS coals) were analyzed by the present method, and the data were compared to those from the authentic microwave-acid digestion (MW-AD) method. For the determination of total S in coal, the OFC method with H2O2 solution as an absorbent followed by ICP-AES or precipitation titration was successfully applied. © 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2007.02.026

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

Seven powdery coals (four SS coals and three Argonne premium coals) were subjected to pyrolysis at 300 °C under a flow of nitrogen, and the release of Hg from coal was examined. The % release of Hg greatly varied from 24 to 83% depending upon the type of coals. In order to remove pyrite from coal, powdery coal was treated with 0.5 M HNO3 at 80 °C. The HNO3-treated coals were also subjected to the 300 °C-pyrolysis, and the release of Hg was evaluated. Even for coals, which gave low %Hg release when the raw coal was pyrolyzed, nearly complete release of Hg was attained when the treated coal was pyrolyzed. The release behavior of Hg was discussed on the basis of the mode of occurrence of Hg in coal. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.powtec.2007.03.004

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Institutional Repository URL

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Microwave-assisted acid digestion (MW-AD) followed by atomic spectrometries such as inductively coupled plasma-atomic emission spectrometry (ICP-AES) was examined for the determination of major and trace elements in coal fly ash (CFA). Effective digestion conditions were studied using four certified reference materials of CFA, with particular focus on the composition of acid mixture and the removal of HF after MW-AD. When MW-AD was conducted without using HF (HNO3+H2O2), the tested elements yielded fairly poor recoveries. When MW-AD with HF (HNO3+HF+H 2O2) was carried out, two methods for HF removal were attempted, H3BO3 addition and evaporation of acids. In the former method, while the recoveries of major elements (Al, Ca, Fe, and Mg) were satisfactory, those of trace elements were not satisfactory; in particular, the recovery of Pb was fairly low. In the latter method, the recoveries of Al, Ca, and Mg were extremely poor; however, those of other elements including the trace elements (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) were satisfactory. In this paper, the optimization of the digestion method for ICP-AES is discussed. Further, the advantages and limitations of ICP-AES in the determination of elements in CFA are assessed. © 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2005.04.034

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Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A novel method for the removal of inorganic arsenic(III) (As(III)), monomethylarsonate (MMA), and dimethylarsinate (DMA) from aqueous media, was proposed and investigated. This method involves the combined use of TiO 2-photocatalyst and an adsorbent, which has a high ability of As(V) adsorption, under photo-irradiation. When an aqueous solution of As(III) was stirred and irradiated by sunlight or xenon lamp in the presence of TiO 2 suspension, the oxidation of As(III) into As(V) was effectively attained. By use of the same photocatalytic reaction, MMA and DMA were also degraded into As(V), while the total organic carbon (TOC) in the aqueous phase was decreased. When an aqueous solution of As(III) was stirred with a mixed suspension of TiO2 and an adsorbent for As(V) (activated alumina) under sunlight irradiation, the arsenic removal reached 89% after 24 h. By use of the same photocatalyst-adsorbent system, 98% of MMA and 97% of DMA were removed. The mechanism of the removal of arsenic species by the photocatalyst-adsorbent system was discussed. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2004.11.030

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Surface characterization of coal fly ash (CFA) was carried out by use of X-ray photoelectron spectroscopy (XPS), especially focusing on the occurrence of As. A peak in the XPS spectrum of CFA was assigned to oxide forms of As(3d). The molar ratios of Al, As, Ca, Fe, and S normalized to Si were obtained from XPS analysis (MR-X). Also, the molar ratios of those elements were calculated from bulk analysis (total element concentration in CFA) (MR-B). The MR-X/MR-B ratio of As was much higher than those of other elements, suggesting that As is highly enriched on the surface of CFA. When eight CFA samples were analyzed, there was an approximate relationship between the MR-X values and MR-B values for As. The leaching of elements from CFA was examined by XPS analysis and by bulk analysis. The leaching tests using EDTA and HNO3 resulted in a great decrease in the As(3d) peak area; the %leaching of As obtained by XPS analysis was almost equal to that by bulk analysis. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2004.12.016

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：Japanese   Publishing type：Doctoral thesis   Publisher：Kagoshima University  

CiNii Research

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

The degradation of phenylarsonic acid (PA) and its derivatives by hydrothermal treatment (HTT) was examined, especially focusing on the effect of adding H2O2 upon the degradation efficiency. The degradation was assessed by the generation of arsenate resulting from the cleavage of As-C bonds in the PA derivatives. When PA (without substituents) was subjected to an HTT with H2O2 (H2O 2-HTT; 0.5-1% H2O2) at 175-200 °C, PA was almost completely degraded into arsenate, whereas an HTT with NaOH (NaOH-HTT; 3 M NaOH) at the temperatures provided almost no degradation. The H 2O2-HTT also worked well for the degradation of PA derivatives with hydroxy and/or nitro groups on the phenyl ring. However, the degradation of aminophenylarsonic acids was not favorably performed by the H2O2-HTT. The effect of the structure of PA derivatives upon the degradation susceptibility was discussed. A photocatalytic reaction using TiO2 was also attempted for the degradation of PA derivatives. Copyright © 2005 John Wiley & Sons, Ltd.

DOI： 10.1002/aoc.720

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The demand for effective and inexpensive adsorbents is to increase in response to the widespread recognition of the deleterious health effects of arsenic exposure through drinking water. A novel adsorbent, aluminum-loaded Shirasu-zeolite P1 (Al-SZP1), was prepared and employed for the adsorption and removal of arsenic(V) (As(V)) ion from aqueous system. The process of adsorption follows first-order kinetics and the adsorption behavior is fitted with a Freundlich isotherm. The adsorption of As(V) is slightly dependent on the initial pH over a wide range (3-10). Al-SZP1 was found with a high As(V) adsorption ability, equivalent to that of activated alumina, and seems to be especially suitable for removal of As(V) in low concentration. The addition of arsenite, chloride, nitrate, sulfate, chromate, and acetate ions hardly affected the As(V) adsorption, whereas the coexisting phosphate greatly interfered with the adsorption. The adsorption mechanism is supposed as a ligand-exchange process between As(V) ions and the hydroxide groups present on the surface of Al-SZP1. The adsorbed As(V) ions were desorbed effectively by a 40mM NaOH solution. Continuous operation was demonstrated in a column packed with Al-SZP1. The feasibility of this technique to practical utilization was also assessed by adsorption/desorption multiple cycles with in situ desorption/regeneration operation. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0304-3894(02)00020-1

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PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Accumulation, transformation and toxicity of arsenic compounds to Japanese Medaka, Oryzias latipes were investigated. For sodium arsenite [As(III)] and disodium arsenate [As(V)], the mean value for 7-day lethal concentration LC50 for O. latipes were 14.6 and 30.3 mg As/l, respectively. Direct accumulation of arsenic in O. latipes increased as a function of As(III) concentration in water. A small proportion of accumulated arsenic was transformed to methylated arsenic. As much as 70% of the total arsenic accumulated in tissue was depurated. Accumulation and transformation of As(III) by O. latipes in a simple freshwater food chain were also investigated. The transformation of As(III) to As(V) by organisms was more prevalent than biomethylation of accumulated arsenic in organisms of the three steps of the food chain. © 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0045-6535(01)00084-4

Web of Science

Scopus

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Bioaccumulation and biotransformation of arsenic (As) compounds in freshwater Tilapia mossambica was investigated. The direct accumulation of As by T. mossambica was proportional to the concentration of arsenicals in water. Small amounts of accumulated As were transformed to methylated As, including trimethylarsenic (TMA) species. Accumulation and transformation of As(III) by T. mossambica via freshwater food chain results in the transformation of As(III) to As(V) with little biomethylation of accumulated As. Approximately 90% of accumulated As was depurated to water. © 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0045-6535(01)00085-6

Web of Science

Scopus

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

The leaching of arsenic from coal fly ash NIST-1633b and NIST-2689 was tried with various lixiviants. The leaching of arsenic was found to have taken place readily and to be dependent on both the equilibria of dissolution/precipitation and adsorption/desorption in the leaching system. The arsenic leaching intensity was significantly elevated by the use of proper chelating agents, which is supposed to be owing to the formation of metal (aluminium and/or iron)-chelate complexes followed by an enhanced binding with arsenate ions. The results of the present study show that arsenic oxides are associated well with iron and aluminium oxide deposits on the particle surface of coal fly ash NIST-1633b. Surface enrichment for arsenic was also examined and confirmed by XPS measurement. The leaching percentages of arsenic on the surface from XPS detection were in good agreement with those in bulk found in the leaching tests.

DOI： 10.1080/02772240109359019

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

The present study deals with the development of an efficient and reliable process for safe disposal of coal fly ash to remove arsenic that has been found to be the most easily leachable and hazardous heavy metal in coal fly ash. Pre-leaching of fly ash prior to disposal by a natural chelating agent, sodium gluconate (SG), was proposed and studied. Several operational factors influencing arsenic leachability, such as concentration of SG solution, liquid to solid ratio, pH, length of leaching time and leaching temperature were examined. Arsenic was found to leach out substantially with SG, but almost no further release was observed from the ash pre-leached by SG. After the pre-leaching treatment, the desirable high buffering capacity of the ash was well sustained. SG solution was effectively regenerated by activated alumina adsorption so that it could be successfully reused for multiple leaching/adsorption cycles.

DOI： 10.1080/02772240109359020

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

Arsenic concentration and arsenic speciation in the liver, intestine, ovary, bone, brain, muscle, gill and eye of the freshwater fish Tilapia mossambica exposed to arsenic were investigated. The profile of arsenic distribution in tissues of T. mossambica after exposure to a medium containing arsenate was brain 〉 intestine 〉 ovary 〉 eyes 〉 muscle 〉 gill 〉 bone 〉 liver. The minimum content of arsenic is in liver tissue (2.5 μgAs g-1 dry weight), whereas the maximum content is in brain tissue (61.8 μgAs g-1 dry weight). Arsenic accumulated in liver tissue was present as methylated arsenic species, and no inorganic arsenic species were found in liver tissue. A notable exception is in brain tissue. Most arsenic accumulated in brain tissue was inorganic arsenic species, and no methylated arsenic was found in brain tissue. In a dietary exposure treatment, the maximum arsenic accumulation in the tissue of T. mossambica fed with Neocaridina denticulata dosed with arsenic from a Chlorella vulgaris diet (via the food chain) is in the ovary (7.4 μgAs g-1 dry weight), followed by gill, liver, muscle, bone, brain, eyes and intestine. Trace amounts of methylated arsenic were found in liver tissue in this treatment. Methylated arsenic in fish exposed via water was more evenly distributed in the organs compared with dietary exposure. Copyright © 2001 John Wiley & Sons, Ltd.

DOI： 10.1002/aoc.211

Web of Science

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SHANXI SCIENCE & TECHNOLOGY PRESS  

Alginic acid was hydrothermally treated at 150 degrees C in an autoclave. By use of the resulting hydrothermally-treated arginic acid (HTTAA), the leaching of Pb from coals, such as NIST-1632b, has been examined. The Pb leaching ability of HTTAA is comparable to that of EDTA.

Web of Science

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SHANXI SCIENCE & TECHNOLOGY PRESS  

An Australian low-rank coal, Loy Yang, was hydrothermally treated at 200-350 degrees C in an autoclave. As the heat-treatment temperature (HTT) is raised, the hygroscopicity of coal gradually decreases and the amount of bound water in coal also decreases. A coal-water mixture (CWM) was prepared from the raw and hydrothermally treated coals by use of an additive, poly(styrenesulfonate) (PSS), and the fluidity and static stability of CWM were assessed. "Achievable coal concentration (ACC)" is defined as the coal concentration in CWM when the CWM viscosity reaches 1.0 pas. The ACC value for raw coal is 33.4 wt%, becoming 62.3 wt% when the 350 degrees C-treated coal is used.

Web of Science

An Indonesian low-rank coal, Adaro, was hydrothermally treated at 200-350°C in an autoclave. The raw and treated coals have been subjected to several analyses which include hygroscopicity, the content of oxygenic functional groups, FTIR spectrum, and specific surface area. When the coal is hydrothermally treated, the hygroscopicity of coal remarkably decreases. The content of carboxyl group in coal greatly decreases as the heat treatment temperature (HTT) is raised. From FTIR analysis, the methyl/methylene ratio in coal somewhat increases, especially when the coal is treated at 350°C
while the aromaticity of coal is enhanced a little. Due to the hydrothermal treatment, the ignition temperature (T i) shifts to a high temperature
whereas the temperature, at which the maximum combustion rate occurs (T m), is not so changed. The change in the properties of coal and the combustion characteristics is discussed. © 1999 OPA (Overseas Publishers Association) N.V.

DOI： 10.1080/07349349908945606

Scopus

Publisher：Maruzen Co. Ltd.  

The properties of coal when the coal was hydrothermally treated at 150-350°C were examined with particular emphasis on the surface properties. The analysis of coal properties includes hygroscopicity, the content of functional groups measured by chemical analysis and FT-IR, elemental analysis, specific surface area, maceral composition, and vitrinite reflectance. Two Australian low rank coals, Loy Yang coal and Yallourn coal, were tested; while a subbituminous coal and a high rank coal were subjected to the same treatment for comparison. When the low rank coals were hydrothermally treated, the hygroscopicity of coal remarkably decreased, becoming comparable to that for high rank coals after the 350°C treatment. The content of carboxyl group greatly decreased as heat treatment temperature (HTT) was raised; whereas decrease in the content of phenolic hydroxyl group was rather small. After the hydrothermal treatment, exinite maceral in the coal almost disappeared and the absorbance for aliphatic carbon in FT-IR spectrum was somewhat raised. From these results, the change in the coal properties during the hydrothermal treatment is discussed.

DOI： 10.3775/jie.77.478

Scopus

Publisher：The Japan Institute of Energy  

CiNii Research

Publisher：一般社団法人日本エネルギー学会  

CiNii Research

Publisher：一般社団法人日本エネルギー学会  

CiNii Research

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Publisher：一般社団法人 日本エネルギー学会  

DOI： 10.3775/jie.91.718_2

CiNii Research

Publisher：一般社団法人 日本エネルギー学会  

DOI： 10.3775/jie.90.738_1

CiNii Research

Publisher：The Japan Institute of Energy  

CiNii Research

Publisher：一般社団法人 日本エネルギー学会  

DOI： 10.3775/jie.89.763_2

CiNii Research

Publisher：一般社団法人 日本エネルギー学会  

DOI： 10.3775/jie.88.681_1

CiNii Research

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/4977

Publisher：Kagoshima University  

CiNii Research

Publisher：Kagoshima University  

Air pollution in Kagoshima City from April 2002 to March 2003 was investigated with particular emphasis on the falling dust (volcanic ash fall) from Mt. Sakurajima. The falling dust was collected monthly together with rainwater at eight locations in Kagoshima City. After the sample had been filtered, the residue was dried and weighed, and the filtrate was analyzed for SO_4^<2->, Cl^-, and water-soluble matter, as well as for pH. The average monthly amount of falling dust at eight locations in Kagoshima City was 6.9 g・m^<-2>・month^<-1>, which was slightly decreased than the value observed in the last fiscal year. Thus, the tendency of low falling dust amount continued, after a period (1999-2000) of relatively high falling dust amount (ca, 50g・m^<-2>・month^<-1>). The weight of water-soluble matter which fell was considerably higher than that for the last fiscal year. NO_2 air pollution was measured by use of the filter-badge method. The highest value for NO_2 concentration was observed at Kagoshima City Hall, however, this figure still meets the value established as the national environmental standard.

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/625

Publisher：Kagoshima University  

Air pollution in Kagoshima City from April 2014 to March 2015 was investigated with particular emphasis on the dust fall (volcanic ash fall) from Mt. Sakurajima. The dust fall was collected monthly with rainwater at eight locations in Kagoshima City. After the sample had been filtered, the residue was dried and weighed, and the filtrate was analyzed for SO4^2-, Cl^-, and water-soluble matter, as well as for pH. The average monthly dust fall at eight locations in Kagoshima City was 55.8 g?m^-2?month^-1, which was 40% decrease from that observed in the last fiscal year. The concentration of NO2 in the air was measured by use of the &quot;filter-badge method&quot;. The average NO2 concentration at the eight locations was 5.8 ppb, which was somewhat lower than that observed in the last fiscal year.

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/608

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/589

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/568

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/530

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/490

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/465

Publisher：Kagoshima University  

CiNii Research

Institutional Repository URL

Other Link： http://hdl.handle.net/10232/466

Event date： 2024.9

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋   Country：Japan  

Event date： 2024.6

Language：Japanese   Presentation type：Poster presentation  

Venue：つくば市   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市   Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Poster presentation  

Venue：福岡市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：熊本市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：熊本市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：熊本市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：熊本市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：神戸市   Country：Japan  

Event date： 2023.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸市   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Poster presentation  

Venue：大阪市   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：松山市   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：松山市   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：松山市   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：松山市   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岡山大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岡山大学   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Poster presentation  

Venue：岡山大学   Country：Japan  

Event date： 2022.9 - 2023.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：オンライン   Country：Japan  

Event date： 2022.9 - 2023.9

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン   Country：Japan  

Event date： 2022.9 - 2023.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：オンライン   Country：Japan  

Event date： 2022.6

Language：Japanese   Presentation type：Poster presentation  

Venue：福岡市   Country：Japan  

Event date： 2022.6

Language：Japanese   Presentation type：Poster presentation  

Venue：福岡市   Country：Japan  

Event date： 2022.6

Language：Japanese   Presentation type：Poster presentation  

Venue：福岡市   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催  

Event date： 2022.3

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Poster presentation  

Venue：WEB開催  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：WEB開催  

Event date： 2020.11

Event date： 2020.10

Event date： 2020.9

Event date： 2020.9

Event date： 2020.9

Event date： 2020.9

Event date： 2020.9

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン  

Event date： 2020.9

Event date： 2020.5

Event date： 2020.3

Event date： 2020.3

Event date： 2020.3

Event date： 2019.11

Event date： 2019.11

Event date： 2019.11

Language：Japanese   Presentation type：Poster presentation  

Venue：鹿児島  

Event date： 2019.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：鹿児島  

Event date： 2019.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：鹿児島  

Event date： 2019.11

Language：Japanese   Presentation type：Poster presentation  

Venue：鹿児島  

Event date： 2019.11

Language：Japanese   Presentation type：Poster presentation  

Venue：鹿児島  

Event date： 2019.10

<p>Coal ash contains hazardous elements such as arsenic, boron, chromium, and selenium. These hazardous elements easily leach into the environment. In order to control their leaching, the aging of coal ash were developed, recently. In this study, the effect s of ash composition, such as calcium content in original coal ash, onto the immobilization ability of arsenic, boron, chromium, and selenium in the aged coal ash was investigated using simulated coal ash samples which have various calcium contents. When high calcium containing simulated coal ash samples were aged for a week, the leaching amount of arsenic, boron, and selenium from the simulated ash samples was effectively reduced and the formation of ettringite was observed on the surface of aged ash samples. From the results, the contribution of ettringite formation to the immobilization of hazardous elements was suggested.</p>

Event date： 2019.9

Event date： 2019.9

Event date： 2019.9

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：千葉  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：千葉  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：千葉  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：千葉  

Event date： 2019.8

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.8

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：埼玉  

Event date： 2019.5

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：北九州  

Event date： 2018.10

<p>Coal fly ash(CFA),which contains hazardous elements such as selenium and boron. These elements are easily leached out to water environment and contaminate the surface and groundwater. The leaching amount of these hazardous elements from CFAs exceeded the environmental standards of soil and landfill sometimes. In this study, effects of aging process on the leaching of hazardous elements from CFAs was examined. The leaching amount of selenium, boron, chromium and fluorine from CFAs decreased with the lapse of aging time. Selenium leaching from aged CFAs was influenced by the calcium content in original CFAs. The results of XRD analysis indicated selenium in aged CFAs was immobilized by hydrated minerals such as ettringite.</p>

Event date： 2018.10

<p>As a result of elution test on coal ash, elution beyond the soil environmental standard value was confirmed. So, it is important to develop a simple analytical method for development of suppression technology. In this study, analysis of fluorine content in coal and coal ash was carried out by simple and quick method of analysis using oxygen flask combustion method (OFC) from the conventional method. We analyzed content by OFC and fluoride ion electrode (FISE) using several coal certified substances. As a result, it was found that the recovery rate tends to be low for samples with high fluorine content and high ash content. It was considered that the mineral that the melting point and decomposition temperature contained in coal is high and the effect of the reaction promoter (WO 3, Sn) can not be obtained lowers the recovery rate.</p>

Event date： 2018.9

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：仙台  

Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：沖縄  

Event date： 2017.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：秋田  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京  

Event date： 2017.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：静岡  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：札幌市  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：札幌市  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：札幌市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡市  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.9

Language：English   Presentation type：Oral presentation (general)  

Event date： 2015.6

Language：English   Presentation type：Oral presentation (general)  

Event date： 2015.6

Language：English   Presentation type：Oral presentation (general)  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2014.10

Language：Japanese  

Venue：宮城  

国内学会

Event date： 2014.10

Language：Japanese  

Venue：宮城  

国内学会

Event date： 2014.10

Language：English  

Venue：ピッツバーグ，米国  

国際学会

Event date： 2014.10

Language：English  

Venue：ピッツバーグ，米国  

国際学会

Event date： 2014.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2014.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2014.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2014.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2014.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2014.5

Language：Japanese  

Venue：京都  

国内学会

Event date： 2014.5

Language：Japanese  

Venue：京都  

国内学会

Event date： 2013.12

Language：English  

Venue：名古屋  

国際学会

Event date： 2013.10

Language：English  

Venue：ペンシルバニア、米国  

国際学会

Event date： 2013.10

Language：English  

Venue：ペンシルバニア、米国  

国際学会

Event date： 2013.10

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2013.10

Language：English  

Venue：福岡  

国際学会

Event date： 2013.9

Event date： 2013.9

Event date： 2013.9

Event date： 2013.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2013.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2013.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2013.8

The concentration of Hg in various kinds of coals, which are varied in production countries, was analyzed by a heat vaporization atomic absorption spectrometry (HVAAS), and the effect of particle size of coal onto the measurable deviation in data was discussed. When the determination of Hg was performed for the SS coal samples in a 60 mesh under powdery samples, some of the coals showed the higher relative standard deviation (RSD) values. When a further small particle size was used, the RSD value in data became small. For the determination of other trace metals, the coal samples with a particle size (ca. 100 mesh pass) did not show such a deviation in data. Also, the relationship between the Hg content in coal and some coal properties was investigated.

Event date： 2013.8

Language：English  

Venue：東京  

国際学会

Event date： 2013.7

Language：Japanese  

Venue：東京  

国内学会

Event date： 2013.7

Language：Japanese  

Venue：東京  

国内学会

Event date： 2013.6

Language：English  

Venue：東京  

国際学会

Event date： 2013.3

Event date： 2013.3

Event date： 2013.3

Event date： 2013.3

Event date： 2013.3

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2013.2

Language：Japanese  

Venue：北九州市  

国内学会

Event date： 2013.2

Language：Japanese  

Venue：北九州市  

国内学会

Event date： 2012.10

Language：Japanese  

Venue：釧路  

国内学会

Event date： 2012.10

Language：Japanese  

Venue：釧路  

国内学会

Event date： 2012.9

Language：Japanese  

Venue：横浜  

国内学会

Event date： 2012.9

Language：Japanese  

Venue：金沢  

国内学会

Event date： 2012.9

Language：Japanese  

Venue：金沢  

国内学会

Event date： 2012.9

Language：English  

Venue：Busan, Korea  

国際学会

Event date： 2012.9

Language：English  

Venue：Kumamoto  

国際学会

Event date： 2012.8

Language：Japanese  

Venue：東京  

国内学会

Event date： 2012.8

Language：Japanese  

Venue：東京  

国内学会

Event date： 2012.7

Language：Japanese  

Venue：松山  

国内学会

Event date： 2012.7

Language：Japanese  

Venue：松山  

国内学会

Event date： 2012.7

Language：Japanese  

Venue：Huangshan, China  

研究会

Event date： 2012.6

Language：English  

Venue：東京  

国際学会

Event date： 2012.6

Language：English  

Venue：Tokyo  

国際学会

Event date： 2012.5

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2012.5

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2012.4

Language：English  

Venue：Shenzhen, China  

国際学会

Event date： 2012.3

Language：Japanese  

Venue：東京  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：東京  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：東京  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：北九州  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：北九州  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：北九州  

国内学会

Event date： 2012.3

Language：Japanese  

Venue：北九州  

国内学会

Event date： 2011.10

Language：English  

Venue：Tokyo, Japan  

国際学会

Event date： 2011.10

Language：English  

Venue：Pittsburgh, USA  

国際学会

Event date： 2011.10

Language：English  

Venue：Tokyo, Japan  

国際学会

Event date： 2011.9

Language：Japanese  

Venue：兵庫, 西宮  

国内学会

Event date： 2011.9

Language：Japanese  

Venue：名古屋  

国内学会

Event date： 2011.9

Language：Japanese  

Venue：名古屋  

国内学会

Event date： 2011.9

Language：Japanese  

Venue：名古屋  

国内学会

Event date： 2011.9

Language：English  

Venue：Kyiv, Ukraine  

国際学会

Event date： 2011.9

Language：Japanese  

Venue：名古屋市  

国内学会

Event date： 2011.9

Language：Japanese  

Venue：兵庫県  

国内学会

Event date： 2011.8

Language：Japanese  

Venue：大阪, 吹田  

国内学会

Event date： 2011.8

Language：English  

Venue：Yinchuan, Ningxia, China  

国際学会

Event date： 2011.8

Language：Japanese  

Venue：大阪, 吹田  

国内学会

Event date： 2011.7

Language：Japanese  

Venue：熊本  

国内学会

Event date： 2011.7

Language：Japanese  

Venue：熊本  

国内学会

Event date： 2011.6

Language：English  

Venue：Berlin, Germany  

国際学会

Event date： 2011.3

Language：Japanese  

Venue：北海道, 札幌  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：府中市、東京  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：札幌市、北海道  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：札幌市、北海道  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2011.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.12

Language：English  

Venue：Fukuoka, Japan  

国際学会

Event date： 2010.9

Se(VI)was hard to remove from the aqueous media by using the conventional removal method, such as adsorption. Therefore, the removal of Se(VI) from the simulated wet FGD waters by use of bioreduction and TiO_2 photocatalytic reduction were investigated. When the bioreduction and photocatalytic reduction systems were attempted for a simple Se(VI) solution, the reduction of Se(VI) to Se(0) precipitate actually occurs and Se(VI) was effectively removed from aqueous media. However, the removal efficiency of Se(VI) was considerably inhibited by some co-existing anions, such as NO_3^- or SO_4^<2-> when these reduction methods were applied for the simulated FGD waters.

Event date： 2010.9

Biodesulfurization of coals by use of Thiobacillus ferrooxidans was examined, and the coking property of the biodesulfurized coal was investigated in terms of button index. The % removal of inorganic sulfur was 40-90% when the biodesulfurization was carried out for three high sulfur coals. Also, the biodesulfurization favorably worked for the removal of As and Se from coal. Moreover, a good correlation was observed between the removal of As from coal and that for inorganic sulfur. For the coking property of the biodesulfurized coal, the button index was not varied. The results suggest that the biodesulfurization is a useful process not only for steam coals but also for coking coals.

Event date： 2010.9

The wet flue gas desulfurization(FGD)waters obtained from a coal combustion system was analyzed especially focusing on the presence of trace hazardous elements. For B and Se, appreciable concentrations are observed in the FGD waters when the coals with higher concentrations of these elements are used. Also, the removal of B, Se, and Hg from a simulated FGD water was attempted. A glucamine-type resin or fiber showed a high adsorption ability for B and Hg.

Event date： 2010.9

Event date： 2010.9

Event date： 2010.9

Language：Japanese  

Venue：岐阜  

国内学会

Event date： 2010.9

Language：Japanese  

Venue：岐阜  

国内学会

Event date： 2010.9

Language：Japanese  

Venue：岐阜  

国内学会

Event date： 2010.9

Language：Japanese  

Venue：京都  

国内学会

Event date： 2010.9

Language：Japanese  

Venue：東京  

国内学会

Event date： 2010.8

The removal of hazardous trace elements, such as B and Se from a wet flue gas desulfurization (FGD) wastewater obtained from a pulverized coal combustion system was examined. B and Hg were effectively removed from the simulated FGD wastewater by use of ion-exchange resins. However, Se was hard to remove from the wastewater by using the adsorption method. The removal of Se(VI) from the simulated FGD wastewater by use of bioreduction and TiO_2 photocatalytic reduction were also attempted. The removal efficiency of Se(VI) was considerably inhibited by some co-exist anions, such as NO_3^- or SO_4^<2-> under both reduction methods.

Event date： 2010.8

Language：Japanese  

Venue：東京  

国内学会

Event date： 2010.8

Language：Japanese  

Venue：東京  

国内学会

Event date： 2010.6

Language：English  

Venue：Yokohama, Japan  

国際学会

Event date： 2010.6

Language：English  

Venue：Yokohama, Japan  

国際学会

Event date： 2010.6

Language：English  

Venue：Guilin, China  

国際学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2010.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2009.11

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2009.11

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2009.11

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2009.11

Language：Japanese  

Venue：鹿児島  

国内学会

Event date： 2009.10

Language：English  

Venue：Chinese Taiwan  

国際学会

Event date： 2009.10

Language：English  

Venue：Chinese Taiwan  

国際学会

Event date： 2009.9

Language：Japanese  

Venue：北海道  

国内学会

Event date： 2009.9

Language：Japanese  

Venue：北海道  

国内学会

Event date： 2009.9

Language：Japanese  

Venue：広島  

国内学会

Event date： 2009.9

Language：Japanese  

Venue：北海道  

国内学会

Event date： 2009.7

Language：English  

Venue：茨城. つくば  

国際学会

Event date： 2009.7

Language：English  

Venue：ハンブルグ, ドイツ  

国際学会

Event date： 2009.7

Language：English  

Venue：茨城, つくば  

国際学会

Event date： 2009.3

Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2009.3

Language：Japanese  

Venue：熊本  

国内学会

Event date： 2009.3

Language：Japanese  

Venue：熊本  

国内学会

Event date： 2008.10

Language：Japanese  

Venue：京都  

国内学会

Event date： 2008.10

Language：Japanese  

Venue：京都  

国内学会

Event date： 2008.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2008.9

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2008.9

Language：Japanese  

Venue：東京  

国内学会

Event date： 2008.3

Language：Japanese  

Venue：愛知  

国内学会

Event date： 2008.3

Language：Japanese  

Venue：愛知  

国内学会

Event date： 2007.11

Language：Japanese  

Venue：静岡  

国内学会

Event date： 2007.10

Language：Japanese  

Venue：秋田  

国内学会

Event date： 2007.10

Language：Japanese  

Venue：秋田  

国内学会

Event date： 2007.9

Language：Japanese  

Venue：徳島  

国内学会

Event date： 2007.8

Language：English  

Venue：富山  

国際学会

Event date： 2007.8

Language：English  

Venue：富山  

国際学会

Event date： 2007.3

Language：Japanese  

Venue：福岡  

国内学会

Event date： 2006.11

Language：English  

Venue：宮崎  

国際学会

Event date： 2006.10

Language：Japanese  

Venue：高知  

国内学会

Event date： 2006.10

Language：English  

Venue：中国  

国際学会

Event date： 2006.10

Language：English  

Venue：中国  

国際学会

Event date： 2006.10

Language：Japanese  

Venue：高知  

国内学会

Event date： 2006.10

Language：Japanese  

Venue：高知  

国内学会

Event date： 2006.9

Language：English  

Venue：ギリシャ  

国際学会

Event date： 2006.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2006.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2006.9

Language：Japanese  

Venue：大阪  

国内学会

Event date： 2006.4

Language：English  

Venue：京都  

国際学会

Event date： 2006.3

Language：Japanese  

Venue：宮城  

国内学会

Event date： 2005.11

Language：Japanese  

Venue：岩手  

国内学会

Event date： 2005.11

Language：Japanese  

Venue：愛知  

国内学会

Event date： 2005.11

Language：Japanese  

Venue：愛知  

国内学会

Event date： 2005.10

Language：English  

Venue：沖縄  

国際学会

Event date： 2005.10

Language：English  

Venue：沖縄  

国際学会

Event date： 2005.10

Language：English  

Venue：沖縄  

国際学会

Event date： 2005.10

Language：English  

Venue：大阪  

国際学会

Event date： 2005.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2005.8

Language：Japanese  

Venue：愛知  

国内学会

Event date： 2005.7

Language：English  

Venue：シンガポール  

国際学会

Event date： 2005.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2005.3

Language：Japanese  

Venue：千葉  

国内学会

Event date： 2004.11

Language：Japanese  

Venue：群馬  

国内学会

Event date： 2004.11

Language：Japanese  

Venue：群馬  

国内学会

Event date： 2004.10

Language：English  

Venue：福岡  

国際学会

Event date： 2004.9

Language：English  

Venue：大阪  

国際学会

Event date： 2004.9

Language：English  

Venue：大阪  

国際学会

Event date： 2004.9

Language：English  

Venue：大阪  

国際学会

Event date： 2004.9

Language：Japanese  

Venue：千葉  

国内学会

Event date： 2004.9

Language：English  

Venue：大阪  

国際学会

Event date： 2004.5

Language：English  

Event date： 2003.3

Language：English  

Event date： 2000.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 1997.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 1997.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 1995.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市   Country：Japan  

Upgrading of low-rank coals, such as Loy Yang and Yallourn coals, has been performed by use of "Hot Water Drying (HWD)" method. Influence of varying the treatment temperature upon coal properties, such as hygroscopicity, functional group content, and specific surface area, has been investigated. As the treatment temperature was elevated, the hygroscopicity of coal decreased; while the content of hydrophilic groups, such as hydroxyl and carbonyl groups, decreased.

Coal contains various hazardous trace elements. For these hazardous elements, especially volatile elements, such as Hg is in great concern, because those elements are likely to be released into air when coal is burned. In this study, we examined the determination of trace elements in coal by use of microwave-acid digestion (MW-AD) followed by inductively coupled plasma mass spectrometry (ICP-MS) or inductively coupled plasma atomic emission spectrometry (ICP-AES), and the effect of MW-AD condition upon the recovery of trace elements was investigated. In addition, the concentration of Hg in coal was measured by use of heat-vapor atomic absorption spectrometry (HVAAS).

The biodesulfurization of nine coals was examined by use of Thiobacillus. ferrooxidans, and the factors which affect the efficiency of biodesulfurization were investigated. The % removal of inorganic sulfur varied from 23-90% depending upon the type of coal. The pH increase in the medium was caused by the leaching of Ca from coal, and the % removal of inorganic sulfur was decreased. The prediction method for biodesulfurization efficiency was developed by use of acid leaching test (0.1M HNO_3). Also the removal of hazardous trace elements, such as As and Hg, from coal during biodesulfurization process was examined.

Six coals were treated by the biodesulfurization with Thiobacillus ferrooxidans, and the removal of inorganic sulfur from coal and the chemical structure change of biodesulfurized coal were investigated. The % removal of inorganic sulfur varied from 37-88% depending upon the increasing of pH in the medium and the leaching of Ca from coal during the biodesulfurization. When the chemical structure change of biodesulfurized coal was measured by FT-IR, it was found that elemental sulfur generated on the surface of the biodesulfurized coal treated in the high medium pH. From the XPS measurement, the reduced sulfur compounds were removed in the PT coal, and the oxidized form sulfur was removed in the SS030 coal.

Se(VI) was hard to remove from the aqueous media by using the conventional removal method, such as adsorption. Therefore, the removal of Se(VI) from the simulated wet FGD waters by use of bioreduction and TiO_2 photocatalytic reduction were investigated. When the bioreduction and photocatalytic reduction systems were attempted for a simple 0.5 mg/L Se(VI) solution, the reduction of Se(VI) to Se(0) precipitate actually occurrs and Se(VI) was effectively removed from aqueous media. However, the removal efficiency of Se(VI) was considerably inhibited by some co-existing anions, such as NO_3^- or SO_4^<2-> when these reduction methods were applied for the simulated FGD waters.

The removal of hazardous trace elements, such as Hg, Se, and B, from a flue gas desulfurization wastewater obtained from a pulverized coal combustion system was examined. B and Hg were effectively removed from the wastewater (simulated wastewater) by use of a glucamine type chelate resin or fiver. However, Se was hard to remove from the wastewater by using the adsorption method. The removal of Se from the wastewater by use of TiO_2 photocatalytic reduction was also attempted. Se(VI) in the wastewater was reduced to Se(0) and effectively removed from the wastewater.

X-ray photoelectron spectroscopy (XPS) was used to quantify the carbon changes and nitrogen forms present in hydrothermally-treated low rank coals (HTT temperatures between 200-350℃) and weathered coals. For HTT coals, the content of carboxyl group greatly decreased due to the treatment, and some quaternary nitrogen species changed to pyridinic form. In case of the weathered coals, the content of carboxyl group increased with the increasing of weathering days, and the content of quaternary nitrogen species also increased.

According to X-ray photoelectron spectroscopy (XPS) analysis for coal fly ash, relatively volatile elements, such as arsenic and lead, was found to be highly concentrated on the surface. Leaching experiments for the ash were performed by use of EDTA or nitric acid, and the leaching of each element was examined by digestion and ICP-AES (whole ash) as well as XPS (surface). Arsenic in fly ash was greatly leached, whereas the leaching of lead was small.

The concentrations of minor and trace metals in coal were determined by use of microwave-digestion and ICP-AES measurement. The values obtained by this method were checked with the certified values for several standard reference materials. The metal concentrations of SS coals (SS001-024) were measured and the obtained values were in good agreement with those from the JIS-method for Al, Ca, Fe, and Mg.

Advanced removal of mercury was attempted by use of extraction method and mild pyrolysis. When sulfur-containing chelating agents were used in the extraction, 30-70% of mercury in coal was extracted to the aqueous solution. The mild pyrolysis at 300℃ for 1h resulted in the removal of 20-80% of mercury in coal. The mercury removal efficiency for the mild pyrolysis was found to be correlated with that for the extraction method.

Determination of arsenic, mercury and lead in NIST standard coals was done using ICP-AES or AAS method. Several tests were also conducted to find a suitable and practical method for the exact determination of the said toxic heavy metals in coal. By use of hydrothermally-treated alginic acid (HTTAA), removal of arsenic and lead in some coal samples was conducted. The leaching ability of HTTAA was comparable to that of EDTA.

The removal of arsenic from coal fly ash was attempted by hydrothermal treatment and chelating agent extraction. When fly ash was hydrothermally-treated at 200℃, ca.80% of arsenic was removed. For the wastewater generated, only the arsenic concentration was over the wastewater quality standards, while those of other elements met the standards. A decomposition product of pectin was found to be an effective aqueous chelating agent. By use of the product, arsenic was also efficiently removed from coal fly ash.

Leaching behavior of B, Se, and other elements from twenty-one of coal fly ash (CFA) was examined. The correlation between the leaching amount and the concentration of element in CFA was investigated. The leaching amounts of B, Ca, Se were essentially dependent upon their concentrations in CFA. The effect of pH in the leachate was assessed, and the leaching of Se tended to increase as the pH in the leachate was elevated. For B, the effect of pH upon the leaching was complex, and when the concentration of Ca was higher in the leachate, the formation of CaB(OH)_4^+ was suggested, resulting in the prevention of leaching.

For three kinds of high-sulfur coals, the biodesulfurization by use of Thiobacillus ferrooxidans was conducted, and the removal of inorganic sulfur as well as that of hazardous trace elements were examined. For As and Se, the removal of trace elements had a correlation with that of inorganic sulfur. However, for Hg, such a correlation was not observed. A subsequent extraction method was performed to clarify the mode of occurrence of trace elements in coal. The removal behavior for trace elements, when the biodesulfurization is carried out, is discussed in terms of the mode of occurrence of these elements.

A model study was carried out for the elution behavior of organic matters in the waste water from coal piles. Organic matters were extracted from sample coals with hot water in the hot extraction process. When the extract temperature was increased, the concentration of organic matters increased in aqueous phase. The ecological influence of water-soluble organic matters from coal was investigated. The extracts of Loy yang coal have an endocrine activity. The same examination was investigated for the elution behavior of organic matters in the waste water from hydrothermal treatment process.