REGENERATION AND CATALYTIC PERFORMANCE OF NI-MO-AL-HMS-H-BENTONITE CATALYST IN HYDROGENATION OF AROMATIC HYDROCARBONS

Abstract

Abstract. Introduction. The physico-chemical and catalytic properties of the bifunctional catalyst Ni-Mo-Al-HMS-H-bentonite were investigated in the hydrogenation of a model mixture of 2-methylnaphthalene and dibenzothiophene. This study aimed to compare the properties of fresh and regenerated catalysts and evaluate their efficiency in this reaction. Results and discussion. Catalyst physico-chemical parameters were analyzed by X-ray photoelectron spectroscopy, temperature-programmed hydrogen reduction, nitrogen adsorption-desorption analysis and thermogravimetric analysis. It was established that nickel and molybdenum are mainly present on the catalyst surface in oxide and sulfide forms that determine its catalytic activity. Textural analysis showed that the catalyst possesses a well-developed mesoporous structure with a monomodal distribution of pore sizes. After the catalytic reaction and regeneration, a decline in the textural characteristics were evaluated. Catalytic tests were carried out at 260°C, hydrogen pressure of 6 MPa and reaction time of 5 hours. The fresh catalyst maintained stable activity for four reaction cycles, while the regenerated catalyst demonstrated high efficiency for three subsequent cycles. Conclusion. The obtained results confirm the potential application of the Ni-Mo-Al-HMS-H-bentonite catalyst in hydrogenation processes of aromatic and sulfur-containing compounds.