The Ultrasonic Treatment as a Promising Method of Nanosized Oxide CeO 2 -MoO 3 Composites Preparation

The influence of ultrasonic treatment (UST) of oxide CeO2-MoO3 system with atomic ratio Ce/Mo = 15:85, 25:75, 50:50, and 75:25 on their properties was investigated. The prepared samples were characterized by means of XRD, ESR, N2 adsorption, FT-IR-spectroscopy, SEM, and TEM methods. The catalytic properties of the samples in selective ethanol oxidation to acetaldehyde and their adsorption capacity relation to dye removal from water solutions were studied. The decrease of oxides particles size with nanoparticles formation as result of CeO2 chaotic destruction and MoO3 anisotropic deformation was established. It was shown that UST leads to an increase of the composition-specific surface area, formation of structural defects, and strong interaction between oxides nanoparticles. The change of physicochemical properties of the compositions as result of their sonochemical treatment leads to increase their catalytic and adsorption properties. The samples obtained after UST demonstrate very promising results in oxidative dehydrogenation of ethanol to acetaldehyde, and the treated composition with ratio Ce/Mo = 50:50 permits to obtain the acetaldehyde yield equal to 96% at reaction temperature 200 °C. On the other hand, sample with Ce/Mo = 75:25 has high adsorption capacity in process of dye removal from water solution.