Transformation of analcime into IMF structure during the synthesis of IMF zeolite

•The phase transformation of analcime into the IMF structure was observed.•The effect of synthesis parameters on the crystallization of IMF was studied.•Various sources of aluminum affect the crystallization mechanism of IMF zeolite.•The impact on the textural and acidic properties was examined.

The transformation of analcime into the IMF structure during the crystallization of IMF zeolite is presented. IMF zeolite was found to show behavior similar to TUN zeolite, i.e. crystallization at the expense of an intermediate. Analcime which appeared first in the reaction mixture was further transformed into the IMF structure for aluminosilicate gels with the initial Si/Al ratio in the range of 15–20, i.e. under conditions being optimal for the synthesis of pure IMF phase and also even when seeding the final gel. The effect of synthesis conditions (Si/Al ratio, temperature, time) on the course of crystallization and properties of the high-silica IMF zeolite was investigated and compared with analcime (having the same Si/Al ratio) prepared from clear solutions not containing any organic template and using the same sources of silicon and aluminum as for the synthesis of IMF. The detailed characterization of prepared samples during crystallization is presented.

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