Crystal structural investigations of Mongolian natural zeolites

We have studied zeolitic rocks discovered in Mongolia using electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD) methods. SEM, XRF and XRD measurements were carried out in the Max Plank Institute of Stuttgart, Germany. Our samples are collected from Mongolian deposits: Tsagaan tsav, Tushig uul, Urgun deposit, Bayan Zurkh Black Mountain and Mandal ovoo. Firstly, we have made chemical element analysis by using X-ray fluorescence spectroscopy which gives chemical contents of samples from all zeolite deposits. Comparing contents of above 5 deposits samples shows us that zeolite of Tushig Mountain, Dornogobi, is has the highest content of potassium and can be identified in potassium clinoptilolite- K (2.56 at %), others belong to clinoptilolite- Na. The main cations are K,Na,Ca,Mg,Fe,Ti for all the samples from the above mentioned deposits. Also, the (Si Al)/O ratio shows that the Mongolian zeolites have comparatively good qualities. We made X-ray phase analysis study on X-ray powder diffractometer Bruker-Axes D8 and refined the X-ray diffraction spectra by using ≪Match! Crystal Impact≫ program. As a result, we established that these zeolites are Na and K type of clinoptilolite with monoclinic symmetry (C2/m). Finally, the exact crystallochemical formula of clinoptilolites can be written as the next: • (Na2.02, K1.81, Mg0.49, Ca0.46, Fe0.36)(Al6.28O30.45) (Si28.47O30.45)·z·H2O for Tsagaan tsav sample. • (K2.56, Na1.69, Mg0.64, Ca0.47, Fe0.78)(Al6.39O28.15) (Si31.17O28.15)·z·H2O for Tushig Mountain sample. • (Na2.34, K1.48, Mg0.86, Ca0.57, Fe0.62)(Al7O29.03) (Si29.07O29.03)·z·H2O for Urgun deposit sample. • (Na2.14, K1.64, Mg0.53, Fe0.64, Ti0.19)(Al6.38O28.95) (Si30.59O28.95)·z·H2O for Bayan Zurh Black Mountain sample. • (Na3.59, K1.17, Ca1.17, Mg0.68, Fe0.30)(Al6.58O28.90) (Si28.65O28.90)·z·H2O for Mandalovoo sample.