Abstract: Molded articles based on pyrogenically prepared silicon dioxide and having the following physical-chemical characteristic data:______________________________________ External diameter 2 to 15 mm BET surface area 50 to 400 m.sup.2 /g Total Pore volume 0.6 to 1.3 ml/g Crushing strength 40 to 120 N Pore size distribution no pores <5 nm in diameter, at least 80% in the range 5 to 40 nm in diameter Composition >95% by weight of SiO.sub.2 remainder Al.sub.2 O.sub.3. ______________________________________These products are produced by compacting pyrogenically prepared silicon dioxide with kaolin and/or graphite, sugar, starch, urea or wax with addition of water, drying the mixture at a temperature of from 80.degree. to 120.degree. C. and comminuting it to form a powder, pressing the powder to form the desired article, and tempering the articles at a temperature of from 400.degree. to 1200.degree. C. for a period of 0.5 to 6 hours. The molded bodies can be used as a catalyst support or catalyst.

Abstract: There are prepared zeolite molded articles which also contain alkali silicate and/or alkaline earth silicate and mineral fibers and/or carbon fibers in addition to the zeolite.

Abstract: There are prepared zeolite molded articles which also contain alkali silicate and/or alkaline earth silicate and mineral fibers and/or carbon fibers in addition to the zeolite.

Abstract: A powdery substance, such as for example pyrogenically prepared silicon dioxide, is subjected to predensification through the utilization of centrifugal force in a centrifuge. Subsequently, the centrifuge receptacles are closed with a free flying piston. Through utilization of the centrifugal force, there is achieved through the use of the free flying piston an additional pressure which is exerted on the predetermined powdery substance.