FEATURES OF OBTAINING HIGH-POROSITY NANOCOMPOSITE Al2O3-SiO2 USING DIFFERENT TYPES OF POOR-FORMERS

Abstract

In this work, the influence of technological parameters, namely pressing pressure and type of pore former, on the
microstructure, volume and distribution of pore sizes during the production of a highly porous nanocomposite based on Al2O3-
SiO2 was investigated. It is shown that the use of urea as a pore former at a pressing pressure of 50 MPa allows obtaining
ceramics with 70% porosity. It was established that, regardless of the type of pore former, in the final structure of the ceramics,
two regions of pore sizes are observed after the removal of the pore former - macropores between agglomerates, and micropores
- between particles inside agglomerates. The use of ammonium chloride, urea and ammonium dicarbonate allows to obtain
pores with sizes from 7 to 16 nm and an area of up to 198 m2
/g.