No abstract

The A, X, and Y zeolites are synthesized from kaolins whose calcination temperature is related to the type of zeolite; the effect of the alkalinity as well as the induction time is considered. It is concluded that the kaolin is used as the supply of the silica and the alumina units necessary to synthesize the zeolites; however, not all the Al and Si atoms that compose the kaolin are useful, so the correlations established between the initial composition of the kaolin and the Si/AI ratio of the zeolite can be misleading. The results are compared with those obtained in the synthesis of zeolites from soluble salts.