METAL-ORGANIC HYBRIDS OBTAINED BY FUNCTIONALIZATION OF MESOPOROUS SILICA

Ordered mesoporous silica materials (MS) were modified with n-propyl-salicylaldimine and acetylacetone by two-steps post-synthesis method. The results were compared with those of amorphous silica gel functionalized by the same procedure. These materials were tested for their metal (Cu, Co, and Mn) adsorption capacity in order to obtain the efficient oxidation catalyst based on the metal complex covalently bonded on modified mesoporous silica. The MS material was synthesized by direct synthesis using a triblock copolymer, Pluronic P123, as a structure directing agent. The MS support and functionalized materials exhibited the structure (XRD patterns and N-2 adsorption-desorption isotherms) and morphology (SEM images) characteristics of the ordered mesoporous sieves. The functional groups grafted on the support surface were identified by FTIR spectra and their amounts by elemental analysis and ATG measurements. The obtained hybrids presented the high adsorption capacity for Cu and Co cations and the very weak adsorption capacity for Mn cations. The obtained metal-organic hybrids were tested in oxidation of cyclohexene with hydrogen peroxide.