ZirconiumI 4400 DOI: 10.1002/chin.201112014

Novel Microporous Zirconium Silicate (K2ZrSi3O9·2H2O) from High Temperature Phase Transformation. — The title compound is synthesized from an aqueous solu-tion of KOH, SiO2, and ZrCl4 (autoclave, 230 °C, 18 h) followed by calcination in air at 910—920 °C for 15—30 h. The samples are characterized by powder XRD, SEM, and 29Si MAS NMR spectroscopy. The microporous compound crystallizes in the orthorhombic space group C2221 with Z = 4. The structure is composed of helicoidal chains of SiO4 tetrahedra linked by ZrO6 octahedra to form a three-dimensional frame-work structure. Because the material loses water upon heating at a relatively low tem-perature of <125 °C it may be an excellent candidate for desiccant air-conditioning sys-tems. — (FERREIRA, A.; LIN*, Z.; SOARES, M. R.; ROCHA, J.; J. Solid State Chem. 183 (2010) 12, 3067-3072, http://dx.doi.org/10.1016/j.jssc.2010.10.013 ; Dep. Chem., Univ. Aveiro, P-3810 Aveiro, Port.; Eng.) — W. Pewestorf

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ChemInform 2011, 42, issue 12 © 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim