| 摘要 |
<p>1. Process for the manufacture of zeolites, in which an aqueous solution of alkali metal aluminate is used, which is subjected to continuous circulation in a closed circuit, and an aqueous solution of alkali metal silicate is progressively introduced into a zone of the circuit in which the aluminate solution has a speed at least equal to 0.25 m/s and a flow rate by weight which is at least equal to five times the flow rate at which the silicate solution is introduced, characterized in that an aqueous solution of alkali metal aluminate is used which contains at least 50% by weight of water and has a molar ratio M2 O:Al2 O3 of between 1.5 and 5, and an aqueous solution of alkali metal silicate containing at least 30% by weight of water and having a molar ratio SiO2 :M2 O of between 1 and 5, where M denotes the alkali metal, and the temperatures of the solutions of aluminate and silicate are respectively regulated between 50 and 100 degrees C and between 15 and 25 degrees C, so as to cause instantaneous crystallisation of alkali metal aluminosilicate without the transitory formation of a gel.</p> |
