| 摘要 |
In a process for the conversion of meta-kaolin into an aqueous alkaline suspension of low-grit, water-containing zeolitic sodium aluminosilicate of the smallest particle size having the molar composition: 0.9 to 1.1 Na2O: 1 Al2O3: 1.8 to 2.3 SiO2 with a water content depending on the degree of drying, which contains at least 99.8% by weight of a particle size of less than 25 mu and has a high cation exchange capability, the improvement consisting of: slowly heating a suspension of reactants to a zeolitization temperature in the range of from 70 DEG to 100 DEG C., with a temperature rise averaging 20 DEG C. within a period of from two to ten minutes, feeding the suspension, preferably before said slow heating, continuously into a reactor having progressively, separately zoned mixing areas with a stage-like effect and having at least seven stages while mixing said suspension sufficiently in the respective stages to avoid sedimentation, maintaining said suspension in the reactor at a preselected temperature in the range of from 70 DEG to 100 DEG C. until the degree of crystallization of the zeolitic sodium aluminosilicate, determined by X-ray, has reached at least 80% of the theoretically possibility crystallinity, and continuously removing an aqueous, alkaline suspension of zeolitic sodium aluminosilicate from the end opposite of the intake end of the reactor. The suspension traverses the reactor at a rate in the range of 1 to 3 cubic meters of suspension per cubic meter of reactor volume and per hour. Reactors preferred for the reaction are an agitator vessel cascade with at least seven vessels, an agitator column with at least seven chambers, and a flowing tube reactor which has a ratio of tube length to tube diameter in the range of 3,000 to 7,000.
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