摘要 |
<p>Shaped alumina particles are obtd. by introducing an aq. slurry contg. a substantial portion of rehydratable alumina to a shaping medium and applying heat to the medium to rehydrate and harden the alumina, followed by curing, drying and calcining the obtd. particles. The medium is (a) a water-immiscible phase into which droplets of the slurry are introduced and shaped by surface tension forces into a spherical beaded form; or (b) tubing which produces alumina in extrude form. The particles are suitable for catalysts and catalyst supports. No additional chemical reagents are required to effect hardening. Less energy is required compared with conventional methods. The prod. has high isotropicity, crush strength and porosity.</p> |