The oxidation of ethylbenzene using dioxygen was carried out applying a new catalytic system—heterogeneous N-hydroxyphthalimide (PS-NHPI) coated with an ionic liquid containing CoCl2. The catalytic system represents a combination of solid catalyst with ionic liquid layer (SCILL) and supported ionic liquid phase (SILP) techniques, wherein the resulting system utilizes CoCl2 dissolved in the 1-ethyl-3-methylimidazolium octyl sulphate ([emim)][OcOSO3]) ionic liquid phase that is layered onto the solid catalyst support. PS-NHPI was obtained by immobilizing N-hydroxyphthalimide on chloromethyl polystyrene resins by ester bonds. It was observed that novel SCILL/SILP systems significantly improved the selectivity toward acetophenone. We also demonstrate that these systems can be separated from the reaction mixture and recycled without appreciably reducing its activity and selectivity.

This paper demonstrates the catalytic activity of ionic liquids with an 1‐alkyl‐3‐methylimidazolium cation ([Rmim][X]) in the oxidation of ethylbenzene as a model hydrocarbon. The interaction between ionic liquids and N‐hydroxyphthalimide (NHPI) were examinated with or without Co(II). The activity of the studied ionic liquids and selected tetraalkylammonium salts ([R4N][X]) is compared. The influence of the structure of the alkyl substituents [R] and anions (in which [X]=[Cl], [Br], or [I]) on the reaction course was determined. The interaction between NHPI and the selected ionic liquids was proven using 1H NMR. It was shown that the formation of hydrogen bonds between the hydrogen atom in the −NOH group in NHPI and the anion [X] in [Rmim][X] influenced the rate of the oxidation reaction by accelerating the formation of the N‐oxyl radical responsible for the NHPI activity.

Studies on the oxidation of α-olefins via the two-stage method are presented. The new method consisted of oxidizing C30+ α-olefins with hydrogen peroxide (2 equiv.) and subsequent oxidation with oxygen. Products with high acid numbers (29–82 mgKOH/g) and saponification numbers (64–140 mgKOH/g) were obtained and compared with products obtained using only hydrogen peroxide or oxygen. It was demonstrated that H2O2 can be partially replaced by oxygen in the oxidative cleavage reaction of α-olefins. N-hydroxyphthalimide in combination with Co(acac)2 demonstrated high activity in the oxidation stage using oxygen.