Precursor heating method, rapid crystallization

As shown in Fig. 2, the catalytic activity of the zeolite prepared by the direct heating method for methanol conversion was higher than that of the zeolite crystallization for 25 days by the standard preparation method. However, deactivation of the catalyst by carbon deposit occurred early in the reaction, just as with the catalyst prepared by the standard method. Differences in crystallite morphology between those prepared by the standard method and the direct heating method would be attributed to the stage of the precursor formation. Therefore, after the precursor formation the rapid heating was adopted as described below. 

---