Acidic montmorillonite(H-mont)-immobilized primary amines (H-mont-NH_2) were prepared and characterized by XRD, solid-state NMR, and elemental analysis. This H-mont-NH_2 was found to be excellent acid-base bifunctional catalysts for one-pot acid-base reaction sequences. For example, tandem deacetalization-Knoevenagel condensation proceeded successfully with the H-mont-NH_2, affording the corresponding condensation product in a quantitative yield. The acidity of the H-mont-NH_2 was strongly influenced by preparation solvent. In addition, the base-catalyzed reactions were enhanced by interlayer acid sites.

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Compacted bentonite is considered to be a promising an engineered barrier in radioactive waste disposal facility due to its suitable physicochemical properties. However, bentonite will be altered by high pH leached solution from concrete, and the alteration may diminish the desirable properties of bentonite. Therefore, the understanding of interactions between bentonite and alkaline solution is important to assess the performance of bentonite in radioactive waste disposal facility. In this paper, several studies on alteration of montmorillonite or compacted bentonite under alkaline conditions are reviewed. Furthermore, some remaining problems are also proposed.

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Porous organic pillared clays have been studied as a shape-selective adsorbent for flat organic molecules. The selectivity causes the stable entrapment of aromatic compounds such as flavors or volatile organic compounds (VOC), leading to the application to adsorbents for these compounds. In this paper, the author exhibits two original approaches for the application of the organic pillared clays as the adsorbent. One is a capsule for an antibacterial material. We applied tetramethylammonium (TMA)-pillared montmorillonite to the capsule of Hinokitiol, a volatile antibacterial compound, in order to prepare antibacterial materials/polymer or cellulose composites. The other is the adsorbent for VOC gases. A biphenylene-pillared ilerite was newly synthesized for the purpose. The material possesses the higher porosity than the conventional organic pillared materials, showing the improved toluene adsorptivity. The author believes that the approaches open up the organic pillared clays to the future applications.

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The structure of water on muscovite (001) surfaces has been investigated by molecular dynamics (MD) simulations. X-ray reflectivity profiles highly reflecting the interfacial structure were directly calculated and compared with those of experiments. The direct comparison has validated the usefulness of MD simulations to understand the real interfacial structure of mica-water system. We observed five distinguished peaks in the density profiles of oxygen of water molecules and these peaks are attributable to the water molecules directly adsorbed on mica, hydrated to K^+ ions on mica, and ordered due to hydrogen bonds with hydrated K^+ ions.

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The distribution and circulation of chemical species in natural water are affected by physicochemical processes during water-mineral (rock) interactions. The physicochemical processes involve dissolution, precipitation, redox reaction and adsorption, etc. Among them, adsorption is believed to be the most important process for governing the chemistry of natural water. In addition to the simple role for removal of the dissolved species from solution, adsorption process initiates the many other physicochemical processes such as dissolution, precipitation, transformation and redox reaction, etc. In present paper, I introduce how the adsorption process can affect the physicochemical processes and summarize the new challenges with this topic.

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In this study, we estimated the amount of carbon storage in carbonized paper sludge (CPS) by considering the carbonization treatment process to paper sludge (PS) as Carbon Capture and Storage (CCS) technology. To estimate the amount of carbon storage, we collected the CPS from PS cooperative treatment factory in Fuji city of Shizuoka pref., and analyzed by XRD, XRF and TG/DTA. The carbonaceous material in CPS was classified by chemical fractionation treatment using soil science method. Especially, the carbon content ratios of CPS were analyzed by CHNS/O Analyzer. The classifying results show that the almost all the carbonaceous material in CPS could be considered "humic material" that were chemically stable. From the analyzing results, it was clear that the total amount of CO_2 was equal to 19.6t-CO_2 form the daily carbonization treatment process. On the other hand, the daily carbonization treatment process needed 5,500m^3 of LNG and exhausting gas treatment required 1,016kWh of electricity. From these processes, the 12.5t-CO_2 emission was estimated. The total amount of carbon storage in the daily carbonization treatment process was calculated at 7.1t-CO_2, and it was equal to 158kg-CO_2 in It CPS. Applying the carbonization process enables to reduce 118.9kg-CO_2 in It dried PS as compared to applying normal incineration process. The results show that the carbonization treatment process can be used as a CCS technology in the limited usage of none incineration treatments such as returning to the soil.

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