화학공학소재연구정보센터
Journal of Molecular Catalysis A-Chemical, Vol.310, No.1-2, 51-58, 2009
Synthesis, characterization of cobalt(II) complex nanoparticles encapsulated within nanoreactors of zeolite-Y and their catalytic activities
Cobalt(II) complex nanoparticles of [14]aneN(4): 1,5,8,12-tetraaza-2,9-dioxo-4,11-diphenylcyclotetradecane [16]aneN(4): 1,5,9,13-tetraaza-2,10-dioxo-4,12-diphenylcyclohexadecane; Bzo(2)[14]aneN(4): dibenzo-1,5,8,12-tetraaza-2,9-dioxo-4,11-diphenylcyclotetradecane and Bzo(2)[16]aneN(4): dibenzo-1,5,9,13-tetraaza-2,10-dioxo-4,12-diphenylcyclohexadecane have been encapsulated in the nanopores of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)cobalt(II)] (diamine = 1,2-diaminoethane, 1,3-diaminopropane, 1,2-diaminobenzene, 1,3-diaminobenzene): [Co(N-N)(2)](2+)-NaY; in the nanopores of the zeolite-Y. and (ii) in situ condensation of the cobalt(II) precursor complex with ethylcinnamate. The new complex nanoparticles entrapped in the nanoreactor of zeolite-Y were characterized by several techniques: BET, chemical analysis and spectroscopic methods (FT-IR, UV-vis, XRD, and DRS). These complexes (neat and encapsulated) were used for epoxidation of styrene with O-2 as oxidant in different solvents. Electronic spectra of the reaction mixture indicated that the oxidation proceeds through a free radical mechanism. (C) 2009 Elsevier B.V. All rights reserved.