Siberian Federal University

The catalysts containing Pd, Ru, Ni deposited on a carbon support oxidized to create acid sites allow to intensify lignin depolymerization and increase monomer yields. To design bifunctional catalysts, it is necessary to understand the mechanisms of reactions occurring on individual (metal or acid) catalytic sites. The hydrogenation process of 2-phenylethyl phenyl ether (PEPE) was studied, simulating the structure of lignin fragments connected by an ether β-O-4 bond in the presence of Pd, Ru, Ni catalysts on a graphite-like support Sibunit. It was shown that the main route of PEPE conversion was hydrogenolysis of PEPE molecules with the formation of ethylbenzene and phenol with their subsequent hydrogenation, respectively, to ethylcyclohexane and cyclohexanol. The presence of acidic species on the support increases the activity of catalysts both in relation to the reaction of hydrogenolysis of the ether bond and in relation to the reaction of hydrogenation of the aromatic ring. The 3 %Ru/C-Ox catalyst on oxidized Sibunit exhibits the highest activity in hydrogenation of aromatic rings of PEPE, without breaking the ether bond. The yield of hydrogenated dimers in the presence of Pd/C-ox is noticeably lower with a simultaneously higher activity in breaking the ether bond