Nickel-containing nanophases as the carriers of catalytic active sites in the ethylene oligomerization in the presence of systems based on Ni(acac)2 and organoaluminum compounds

The nature and size of particles, formed under conditions of the ethylene oligomerization in the systems based on nickel bis(acetylacetonate) with Et₂AlCl or Et₂AlCl·Cl₂AlEt (Al: Ni=50: 1), have been determined using ex situ HRTEM, electron diffraction and EDAX in combination with EPR spectroscopy and kinetic studies. It was revealed that the average sizes of Ni-containing particles depend on the nature of cocatalyst and are ∼3.5 and ∼6 nm for the systems derived from Et₂AlCl and Et₂AlCl·Cl₂AlEt, respectively. It was shown that these nanoparticles act as the carriers of catalytically active sites during the C₂H₄ conversion.