Cubic analcime and analcime-zirconia composite with the Si/Al ratio of 2.04 and 2.16, respectively, was synthesized by hydrothermal treatment of coal fly ash cenospheres (Si/Al ¼ 2.7) at 150 C. The scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), synchronous thermal analysis (STA) methods were used to study the morphology, composition and structure of the products. Two main types of analcime bearing particles were obtained, such as hollow microspheres with attached analcime icositetrahedra of 5 e50 mm in size and individual analcime crystals of a narrow particle size distribution (D m ¼ 41 mm) with incorporated zirconia (4.8 wt% Zr). The high quality of the crystalline fractions allowed an accurate fullprofile PXRD analysis of complete analcime crystal structure and composition including anisotropic displacement parameters of all atoms and H-positions of water molecules.

The structure–composition relationship of blocklike ferrospheres (FSs) isolated from fly ash from the coal and lignite combustion has been studied systematically by scanning electron microscopy and energy dispersive X-ray spectroscopy. Groups of globules for which the gross composition of polished sections corresponds to the general equations for the relationship of the concentrations SiO2 = f(Al2O3) and CaO = f(SiO2) are highlighted from FSs of two series. It is shown that blocklike FSs are formed during the sequential transformation of dispersed products of thermal conversion of mineral precursor associates: pyrite, quartz, and Ca, Al-humates in the case of brown coal; and pyrite, siderite, quartz, and calcite in the case of coal. Anorthite is the aluminosilicate precursor of blocklike FSs of both series. The dependence CaO = f(SiO2) that reflects the influence of glass-forming components reveals six groups of FSs. An analysis of SEM images of polished globule sections demonstrates that an increase in the concentration of glass-forming components in all groups is accompanied by gradual changes in the structure of globules, from a large blocklike type to a fine crystalline type with a high glass-phase content. The size and shape of crystallites are controlled by the size of a local melt area where the total concentration of spinel-forming oxides exceeds 85 wt %. An increase in the glass-phase concentration and a decrease in the crystallite size in globules with FeO ≤ 46–50 wt % are explained by expansion of the segregation region in the FeO–Fe2O3–SiO2 system as the oxidation potential rises.

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The composition and physicochemical characteristics of polysaccharides extracted from spent liquors of catalytic and noncatalytic delignification of larch wood in the acetic acid-hydrogen peroxide medium were studied. The following were used as catalysts: (NH 4 ) 6 Mo 7 O 24 , MnSO 4 , TiO 2 , and ZnSO 4 . The structure of polysaccharides was identified by FTIR and NMR spectroscopy. Their composition was established using gas chromatography, and the physicochemical characteristics were studied using gel permeation chromatography, scanning electron microscopy, thermogravimetric analysis, gas adsorption, and elemental analysis. It was shown that in the process of oxidative delignification, a significant amount of hemicelluloses and arabinogalactan passes into the spent liquor. The yield of polysaccharides was up to 16.9 wt%. Polysaccharides had a weight-average molecular weight of up to 22.9 kDa and a narrow molecular weight distribution.