Zeolite formation characteristics in silicate and phosphate systems

We have done a comparative analysis of zeolite formation in silicate (Si), aluminosilicate (AlSi), aluminophosphate (AlP), and silicoaluminophosphate (SiAlP) systems under similar conditions (composition, T_cr, τ_cr). We have determined the following series for zeolite-forming ability: AlP>SiAlP≫Si>SiAl. The considerably higher zeolite-forming activity of phosphate systems is explained by the structural lability of the aluminophosphate framework and the characteristics of the zeolite-formation mechanism. L. V. Pisarzhevskii Institute of Physical Chemistry, National Academy of Sciences of Ukraine, 31 Prosp. Nauki, Kiev 252039, Ukraine. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 33, No. 2, pp. 115–119, March–April, 1997.