| abstract |
Compacts based on pyrogenic silicon dioxide with the following physico-chemical characteristics: Outer diameter: 2 to 15 mm BET surface: 50 to 400 m² / g Pore volume: 0.6 to 1.3 ml / g Breaking strength: 50 to 150 N. Pore distribution: no pores <5 nm in diameter Composition: > 99% by weight SiO₂ Abrasion: <1.0% Bulk density: 400 to 500 g / l are produced by homogenizing pyrogenic silicon dioxide with urea, methyl cellulose and / or magnesium stearate, graphite, aluminum stearate with the addition of water, drying at a temperature of 80 to 120 ° C, crushing to a powder, pressing the powder into compacts and during a Heat for a period of 0.5 to 8 hours at a temperature of 400 to 1200 ° C. |