Mechanism of the Cojoint Effect of Components of the Ni/HMOR/\({\text{SO}}_{4}^{{2 - }}\)–ZrO₂ Catalytic System on the Hydroconversion of Aromatic Hydrocarbons

Composite catalyst (CC) Ni/HMOR/ \({\text{SO}}_{4}^{{2 - }}\) –ZrO₂ is used to study the hydroconversion of benzene and toluene at atmospheric pressure, a temperature of 180°C, WHSV = 2 h⁻¹, and Н₂/ArH = 8. The conversion of benzene is as high as 58.2%. Adding an alkyl substituent raises conversion to 78.5%. It is shown that the primary conversion of toluene is similar to the conversion of benzene through selective aromatic ring hydrogenation with its subsequent isomerization, ring reduction, and hydrocleavage. Components of the catalytic system are inactive in the hydroconversion of aromatic hydrocarbons. Synergism emerges in the hydrogenating CC activity due to the cojoint effect which individual inactive \({\text{SO}}_{4}^{{2 - }}\) –ZrO₂ and Ni/HMOR components of this system have on the reaction. The probable mechanism of the hydrogenation of aromatic hydrocarbons is discussed. It is hypothesized that hydrogenating activity synergism results from the radical reaction becoming one of an ion radical.