| 摘要 |
<p>In the prodn. of binder-free mouldings from active alumina and mol. sieve zeolites, the unground mixt. of the starting materials is pressed dry between rollers under a press. of is not 1 t/cm roller width, then the granulate formed is moistened with the amt. of water needed to hydrate the alumina and opt. the zeolite. The granulate is kept for is not 5 h at 50-100 degrees C and then activated at 250-450 degrees C in a dry gas stream. The process is simpler than the original one, in which the starting materials were powdered finely before mixing and water was added before or duing granulation. In an example, for (a) a granulate prepd. from 40% active alumina and 60% zeolite A by the above method, (b) a zeolite A granulate contg. 80% zeolite and 20% bentonite as binder, the calcination loss was (a) 2.20, (b) 2.50%; water absorption (a) 16.0, (b) 16.8% at 10% RH and (a) 26.7, (b) 21.7% at 60% RH and attrition loss (a) 0.24, (b) 0.05%.</p> |
