On the variation in the composition of zeolite NaA crystals

The conditions for crystallization of zeolite NaA, whose small cages are partially or completely (one molecule per unit cell) filled with NaAlO₂ molecules, were outlined. These molecules are occluded into cuboctahedra of zeolite NaA only during crystallization rather than during formation, aging, and modification of the initial aluminosilicate gels. Based on the data on the adsorption capacity for water in NaA zeolite samples, a small cage of this zeolite (cuboctahedron) adsorbs about four water molecules.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1565–1569, August, 2004.