SYNTHESIS, CHARACTERIZATION AND CATALYTIC ACTIVITY OF AMORPHOUS AL,SIOX GELS FROM WEAKLY ACIDIC AQUEOUS-SOLUTIONS

Al,SiOx gels have been prepared by reaction of different inorganic alu minium compounds with silicic acid. Characterization by chemical analy sis, Al-27 MAS NMR spectroscopy and adsorption measurements shows that the gels obtained from a mixture (pH ca. 3) of basic aluminium chlori des and silicic acid in water are porous and contain tetrahedrally coo rdinated aluminium in the framework. IR spectroscopy and TPDA measurem ents confirm that Bronsted and Lewis acid sites are present in the gel s. Finally, catalytic activity was found in hex-1-ene isomerization.