Synthesis and physicochemical properties of silica gels with small additives of aluminium and zirconium ions
Анотація
The method of synthesis of silica gels containing small additives of Al and Zr ions was developed. The porous structure of the synthesized Al,Zr-silica gels has been characterized by the adsorption method. It was found that simultaneous modification of silica gels by aluminium and zirconium ions lead to the formation of micro- and ultramicroporous samples in neutral media of precipitation. The parameters of porous structure of Al,Zr-silica gels are considerably dependent on the modified ions contents. A supposition was made that the formation of porous structure was caused by mutual stabilizing effect of Al and Zr additives on silica gel globules growth at sol-gel stages of synthesis. The nature of surface active sites of the modified silica gels was studied by the diffuse-reflectance IR-spectroscopy with the use of adsorption of deuteroacetonitrile.
Посилання
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