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By cation exchange for clinoptilolite tuff from the Khonguruu deposit (Yakutia) the Mg-, Ca-, Sr-, Bamodified heulandite-clinoptilolite zeolites are obtained. Based on the data of powder X-ray diffraction and thermal analyses, the properties of these modifications are characterized. Using nitrogen cryosorption, the specific surface areas are determined. Found that the specific surface areas of the cationic modifications obtained increase with the ion charge.

The structure of zeolite water in single crystals of natural zeolites represented by clinoptilolite Na2K2Ca[Al6Si30O72]·22H2O and heulandite Ca3Mg[Al8Si28O72]·24H2O is studied with 1H NMR. Below 170 K the distribution of H2O over the structural positions is shown to be fixed but different for the two minerals. Above 290 K translational and orientational diffusion of zeolite water molecules is observed and the structure of water is almost identical in both heulandite and clinoptilolite. Diffusion mechanism may be associated with the interaction between librational modes of H2O and high-frequency oscillations of aluminosilicate framework. The microwave absorption is shown to be caused in certain conditions by this type of interaction.

The1H NMR spectra of the hydrated monocationic forms of clinoptilolite M6[Al6Si30O72]·nH2O (M=Li, Na, K, Cs, NH4; n=12–22) and M 3 ′ [Al6Si30O72]·nH2O (M′=Mg, Ca, Sr, Ba; n=20–24) and heulandite M8[Al8Si28O72]·21H2O (M=Na, K) are divided into three types differing in the symmetry of tensors of magnetic dipole-dipole interactions of protons in zeolite water molecules. On the basis of model calculations it is shown that water molecules in the Cs, K, and Ba forms of clinoptilolite and the K form of heulandite are ordered in structural positions.