Preparation and Properties of MoO3−TiO2−SiO2 Composites with Spherical Shape of Agglomerates

Resumo

MoO₃−TiO₂−SiO₂ composites with spherical shape of agglomerates were prepared by thermal decomposition of TOKEM-400 and TOKEM-840 anion-exchange resins preliminarily loaded with \({\rm{M}}{{\rm{o}}_7}{\rm{OO}}_{24}^{6 -}\) ions with the applied sol based on tetrabutoxytitanium with tetraethoxysilane. The phase and chemical compositions of the composites were determined by X-ray diffraction and electron probe microanalysis. The influence of the resin type on the surface morphology of MoO₃−TiO₂−SiO₂ composites was demonstrated. To obtain the MoO₃−TiO₂−SiO₂ composite with the spherical shape of agglomerates, it is necessary to use TOKEM-400 resin characterized by higher sorption capacity for \({\rm{M}}{{\rm{o}}_7}{\rm{O}}_{24}^{6 -}\). ions due to exchange of the OH− ions of the resin for \({\rm{M}}{{\rm{o}}_7}{\rm{O}}_{24}^{6 -}\). The temperature conditions for preparing spherical MoO₃−TiO₂−SiO₂ composites were suggested. The total capacity and sorption capacity for \({\rm{M}}{{\rm{o}}_7}{\rm{O}}_{24}^{6 -}\) of TOKEM-400 and TOKEM-840 anion-exchange resins were determined.