Journal of Catalysis, Vol.323, 45-54, 2015
Heterogeneous complexes of nickel MCM-41 with beta-diimine ligands: Applications in olefin oligomerization
The beta-diimine ligands 2-(phenyl)amine-4-(phenyl)imine-2-pentene and 2-(2,6-dimethylphenyl)amine-4-(2,6-dimethylphenyl)imine-2-pentene were combined with the alkoxysilane group chloropropyltrimethoxysilane (CPTMS) and covalently anchored to a mesoporous MCM-41 support; they were ordered via interactions with the silanols of the silica matrix and complexed with nickel. The complexes were synthesized for use in ethylene and propylene oligomerization and for comparing the results of homogeneous and heterogeneous systems. The support was first synthesized, calcined, anchored to the ligand, and then, complexed with nickel. These materials were characterized using various techniques, such as H-1, C-13, and Si-29 NMR, small angle XRD, thermogravimetric analysis, adsorption isotherms, transmission electron microscopy, and flame atomic absorption spectroscopy, to confirm the success of the synthesis. Both homogeneous and heterogeneous complexes are active and selective for the reactions of ethylene and propylene oligomerization. (C) 2014 Elsevier Inc. All rights reserved.