DIE-FORMED ARTICLES BASED ON PYROGENIC SILICON DIOXIDE, PROCESS FOR THEIR PREPARATION AND THEIR USE

摘要

Die-formed articles based on pyrogenic silica having the following physical-chemical data:… … external diameter                                 2 to 15 mm BET surface area                              50 to 400 m<2>/g pore volume                                  0.6 to 1.3 ml/g breaking strength                                40 to 120 N pore distribution       no pores of <5 nm diameter, at least                         80 % in the range from                         5 to 40 nm diameter composition           >95 % by weight of SiO2, the remainder                       being Al2O3 … are produced by compacting pyrogenic silica with kaolin and/or graphite, sugar, starch, urea and wax with addition of water, drying at a temperature from 80 to 120 DEG C, comminution to give a powder, pressing the powder to give die-formed articles and heat-treating these for a period of 0.5 to 6 hours at a temperature from 400 to 1200 DEG C. …The die-formed articles can be used as a catalyst support or catalyst.