Zeolites germanate

Nowak and M. Ziolek, in Proc. 3rd Polish-German Zeolite Colloquium, M. Rozwadowski (Ed), Nicholas Copernicus University Press, Torun 1997, p. 161. 

I.Nowak and M.Ziolek, Third Polish-German Zeolite Conference, edited by M.Rozwadowski (N. Copernicus University Press, Torun 1998), p.l61. 

H. Kosslick, H. Miessner, B. Parlitz, Proc. of the 6th German Zeolite Conference, Bochum (1994)... 

M. O Keeffe and O.M. Yaghi, Germanate Zeolites Contrasting the Behavior of Germanate and Silicate Structures Built from Cubic T802o Units (T = Ge or Si). Chem. Eur. J., 1999, 5, 2796-2801. 

Y. Zhou, H. Zhu, Z. Chen, M. Chen, Y. Xu, H. Zhang, and D. Zhao, A Large 24-Membered-ring Germanate Zeolite-type Open-framework Structure with Three-dimensional Intersecting Channels. Angew. Chem., Int. Ed., 2001, 40, 2166-2168. 

Kukla V, Hahn K, Karger J, Kornatowksi JJ, Pfeifer H (1995) In Rozwadowski M (ed) Proc 2nd Polish-German Zeolite Colloquium Torun. Nicholas Copernicus Univ Press, Torun, Poland, p 110... 

Karge HG (1998) In Rozwadowski M (ed) Proceedings of the 3rd Polish-German zeolite colloquium, Torun, April 3-5 1997. Nicholas Copernicus University Press, Torun, p 11... 

Bornhauser P, Bougeard D (1997) Proceedings of the 9th German Zeolite Meeting (9. Deutsche ZeoUthtagung), Halle, Germany, March 3-15,1995, University of Halle, 1997, p32... 

In 1998, Li and Yaghi reported the synthesis of two pure-germanate zeolites denoted ASU-7 (ASV) and ASU-9 (AST) in the presence of and pyridine, using dimethylamine and l,4-diazabicyclo[2,2,2]octane (DABCO) as an OSDA, respectively. " After a while, Conradsson et al. synthesised FOS-5 (BEG), the first zeolite beta polymorph C, from... 

Independent of the pure-germanate zeolite syntheses described above, on the other hand, it was in 1995-1997 that Camblor and Valencia found a gradual change in the crystallised product caused by increasing the amount of Ge in the synthesis mixture containing TEA ion as an OSDA for the synthesis of pure-sihca Beta zeolite in fluoride media. 

Chodorowski, S., Leboda, R., Brei, V.V., Khomenko, K.N. and Turov, V.V. 1998. The water adsorption on silicate surface studied by H NMR spectroscopy method. In Rozwadowski, M. (Ed.) Proceedings of the Third Polish-German Zeolite Colloquium. Nicolaus Copernicus University Press. Torun, pp. 63-73. 

J. Weitkamp, S. Ernst, H.G. Karge and R. Schneider, Proc. Int. nf. on Catalysis and Adsorption by Zeolites, Leipzig, German Democratic Republic, August 20-23, 1990, accepted for publication. 

Difluorobenzenes are isomerized under gas-phase conditions in the presence of metallosilicates, containing the structure of pentasil zeolites with isomorphic substitution of some silicon atoms by aluminum, gallium, or iron.4 A German patent describes the isomerization of l-bromo-2,4-difluorobenzene to l-bromo-3,5-difluorobenzene in pentasil-type zeolites in an autoclave at 320 C and 25 x 105 Pa for 1 h, giving 29% conversion and 73% selectivity.5... 

To study rapid reactions, traditional batch and flow techniques are inadequate. However, the development of stopped flow, electric field pulse, and particularly pressure-jump relaxation techniques have made the study of rapid reactions possible (Chapter 4). German and Japanese workers have very successfully studied exchange and sorption-desorption reactions on oxides and zeolites using these techniques. In addition to being able to study rapid reaction rates, one can obtain chemical kinetics parameters. The use of these methods by soil and environmental scientists would provide much needed mechanistic information about sorption processes. 

Bu, X. H., Feng, P. Y. and Stucky, G. D. Isolation of germanate sheets with three-membered rings a possible precursor to three-dimensional zeolite-type germanates, Chem. Mater., 1999, 11, 3423-3424. 

The moat favourable pH range lies between 9 and 11. Other oxides containing the main part of Qe co-precipitate with the HFI-type zeolitea in neutral or acidic medium. In a very alkaline madium, the formation of soluble germanatea restricts the incorporation of germanium in the zeolite. Moreover if the pH is adjusted with alkali or ammonium hydroxide, the corresponding germanates admix with an almoet purely silioeous HFI-type zeolite. These difficulties oan be... 

In 1977, the German firm Hankel patented the use of synthetic zeolites as a partial replacement for phosphates. The sodium aluminum silicates as zeolites have a particular lattice structure capable of absorbing heavy metal cations through ion exchange process. The role of zeolites that were added to TPS was to soften water by rapid reaction with calcium at normal temperature [4]. 

Chemistry of Zeolites and Related Porous Materials 2.5.7 Germanates with Extra-large Pores... 

The first attempt to employ ion exchange for commercial purposes was in 1896 by F. Harm, a German agricultural chemist, to remove Na and from sugar beet juice. The first synthetic ion exchange compounds were aluminum silicates called zeolites and were available commercially about 1903. 

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