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.

The heats of immersion (in water) of outgassed clinoptilolite and its ion-exchanged forms were measured with a Calve calorimeter at 30°C, and the integral heats of sorption were calculated therefrom in order to use zeolites in heating and cooling applications. The immersion and sorption heats were studied as functions of the water saturation degree and the cation contents. The changes observed in the slopes of the sorption curves at low saturation for Ca2+ and Mg2+ ion-exchanged forms were related to the thermal destruction of the heulandite-type structure.

The Li-, Na-, K-, Cs-, Ca-, Ba-, and NH4-forms of natural clinoptilolite from the White Stratum deposit, Bulgaria, have been obtained by ionic exchange in solutions. The1H NMR spectr of the samples have been recorded at room temperature and the dipole-dipole coupling constants of zeolite water protons have been measured. The characteristics of regular redistribution of water molecules in structural positions of clinoptilolite upon substitution of exchange Na and Ca cations by the larger K and Ba cations have been established.