A process for the oligomerization of olefins

The invention is a catalyst system consisting of: a) a support material selected from at least one of the following materials: silica, alumina, magnesia, zirconia and mixed oxides thereof, carbon nanotubes; b) an ionic liquid; c) a catalytically effective composition containing nickel; d) an activator selected from the group of Lewis acids with alkylating properties. Next provides for the use of the novel catalyst systems in the oligomerization of unsaturated hydrocarbon mixtures.