| 摘要 |
To improve the resistance to compression of moulded bodies made of titanium dioxide and having a mean particle size d50 of between 0.01 and 50 mm, said bodies are made of primary crystallites of anatase-type titanium dioxide, have a specific surface area of between 20 and 150 m2/g, a porosity of between 0.1 and 0.45 cm3/g and a pore diameter of between 100 and 300 ANGSTROM . The above moulded bodies are prepared either by pelleting of a pasty mixture of titanium dioxide powder and titanium dioxide sol and/or 1-20 % nitric acid, followed by dehydration and calcination at a temperature of between 400 and 1000 DEG C for between 0.5 and 3.5 hours; or by preparing pellets from the titanium dioxide powder and added water, annealing of the pellets at between 300 and 500 DEG C, saturation of same with titanium dioxide sol or 1-20 % nitric acid in a vacuum, followed by drying and finally annealing at a temperature of between 400 and 1000 DEG C for between 0.5 and 3 hours. The moulded bodies can be used, for example, as catalysts, photocatalysts, catalyst carriers, filters/sintered pieces, the stationary phase in chromatography, carriers for slow-release pharmaceuticals and oxygen sensors.
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