There is a higher demand for naturally derived organic fillers than for conventional inorganic fillers, which have a greater environmental impact. For example, cellulose is commonly available organic filler ; however its dispersion in the matrix such as polymers may be poor depending on the base material, and it cannot even form a complex. In this study, we focused on paramylon, which is a naturally derived polysaccharide having unique physical properties. Using a universal testing machine EZ Graph-10 kN, we compared the physical properties of a compound containing 100 polypropylene, 20 paramylon, and 5 maleic-acid-modified low-molecular-weight polypropylene resin as a compatibilizer, with a filler-free compound of the same formulation It was found that with increasing paramylon, the maximum point stress and elasticity increased, while the maximum point displacement decreased. This result suggests that paramylon is a novel prospective filler material.

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In coal-fired power plants, selective catalytic de-NO_x systems are widely used and offer a very efficient method to reduce NO_x emissions from such plants. However, de-NO_x catalyst degrades in long-term operation and catalysts must be periodically exchanged. Exchange of catalysts costs a great deal, hence there is a strong economic incentive to elucidate the degradation mechanism of catalysts and optimize the operation conditions of de-NO_x equipment. In this study, fluorescent X-ray analysis is performed to investigate the elemental distribution on the catalyst surface. Also, X-ray absorption fine structure (XAFS) analysis is applied to determine the chemical form of Vanadium in the catalyst. The results show that elements found in fly ash are detectable in the upstream region near the inlet, whereas such elements are not detected in the downstream region near the outlet. This tendency is in good qualitative agreement with the author's previous numerical result. Vanadium in the fresh catalyst is mainly in its 3+ valence state, whereas that in used catalyst is mainly in the 4+ or 5+ valence states. The ratio of vanadium in 5+ valence state is larger in the inlet region than in the downstream region. This is due to turbulent eddy mixing which promotes vanadium oxidation in the inlet region.

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Reactive crystallization or precipitation is the production process of sparingly soluble precipitate by liquid-liquid or gas-liquid reactions. It is a key production step for a wide range of chemical, pharmaceutical and bio industries to produce particles with desirable characteristics, such as appropriate crystal size and sharp crystal size distribution. Following cooling and evaporation crystallizations, reactive crystallization is utilized widely. In this review reactive crystallization experiments of sea water resources and greenhouse gas, carbon dioxide, are discussed.

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A tannin gel (TG), synthesized from condensed tannin molecules, has a remarkable ability to adsorb metal ions in aqueous solutions. In the present report, the author introduces his recent work on the amine-modification of the TG to improve the adsorbability for precious metal ions. The solid-state ¹³C-NMR measurements revealed that some hydroxy groups in the TG are substituted by amino groups through a simple ammonia treatment. The adsorption experiments for palladium, platinum, and rhodium ions, Pd(II), Pt(IV), and Rh(III), were conducted using the amine-modified tannin gel (ATG), and it was found that the adsorbability of the ATG for these precious metal ions is significantly higher than that of the TG.

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