Structure and Properties of the Crystalline-Silicon-Dioxide-based Macroporous Ceramics

A. I. Rat’ko, A. I. Ivanets, T. A. Azarova, and S. M. Azarov

Institute of General and Inorganic Chemistry, National Academy of Sciences of Belarus,
ul. Surganova 9/1, Minsk, 220072 Belarus

Received June 15, 2007

Abstract — Samples of macroporous ceramics based on crystalline silicon dioxide-(the pore diameter >50 m) with superficial membrane layers (the pore diameter 10–20 m) are obtained. They meet the demands to porous materials for filtering. The samples based on the polydisperse powder of crystalline silicon dioxide with granulometric composition 100–315 m, containing 11 wt % of silica-alumina binder, were formed under a pressure of 30 MPa; they demonstrated an optimal combination of porosity and mechanical strength. After thermal treatment the samples’ porosity came to 30%; the ultimate stress (compression) limit, to 35 MPa. It is shown that multilayer elements for filtering, with membrane layers formed of the silicon dioxide powder suspension, provide the water purification from iron impurity (from 1–2 mg/l and down to 0.3 mg/l, a sanitary standard). The elements for filtering with doubly deposited crystalline silica-based membrane layer (the particle size 10–50 m) showed optimal combination of operation characteristics and the purity of water from iron.

PACS numbers: 81.05.Je, Mh