摘要 |
Crystalline zeolite powder of Type A is employed as a phosphate substitute in washing agents. For this use, it is advantageous if the crystalline zeolite powder of Type A has a specific average particle diameter of 4.3 to 8.5 mu as well as a specifically narrow particle size distribution. By a specific sequence in the addition of the reactants in the precipitation of zeolites A this requirement of the product is fulfilled. Thereby water is present in a receiver and there are simultaneously added sodium aluminate liquor and waterglass solution and subsequently after a long stirring phase there are added further sodium aluminate liquor and further waterglass solution. The maximum grit content of the zeolite powder of Type A obtained is 0.2%.
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