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A new route for the synthesis of titanium silicalite-1

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: A. Vasile and A.M. Busuioc-Tomoiaga

Editorial: elsevier, Materials Research Bulletin, 47, p.35 - 41, 2012.

Rezumat:

A new and efficient route using inexpensive reagents such as fumed silica and tetrapropylammonium
bromide is proposed for the synthesis of titanium silicalite-1. High crystalline titanium silicalite-1 was
obtained in alkaline medium, using sodium hydroxide as HO ion source required for the crystallization
process. Hydrolysis of titanium source with formation of insoluble oxide species was prevented by
titanium complexation with before structuring gel. The final solids were fully characterized by powder Xray
diffraction, scanning electron microscopy, Fourier transform infrared, ultraviolet-visible diffuse
reflectance, Raman and atomic absorption spectroscopies, as well as nitrogen sorption analysis. It was
found that a molar ratio Ti:Si of about 0.04 in the initial reaction mixture is the upper limit to which well
formed titanium silicalite-1 with channels free of crystalline or amorphous material can be obtained.
Above this value, solids with MFI type structure containing both Ti isomorphously substituted in the
network and extralattice anatase nanoparticles inside of channels is formed.

Cuvinte cheie: titan-silicalit-1, zeoliti, materiale microporoase // titanium-silicalite-1, zeolites, microporous materials