Activity of Rh-containing catalysts in Naphthalene Hydrogenation under Pressure

Three Rh-containing catalysts were investigated in the vapor-phase hydrogenation of naphthalene at 6.0 MPa: i) 1.0 wt.% in a MCM41-type mesoporous aluminosilicate (Si/Al=20 as atomic ratio, a.r) (CAT1); ii) 2.0 wt.% in a HMS-type mesoporous aluminosilicate (Si/Al=20 a.r.) (CAT2); iii) 2.0 wt.% on a microporous Al/Ce/Mg pillared layer montmorillonite (CAT3). The following order of hydrogenation activity for weight unit of Rh was detected: CAT1>CAT3>CAT2, while the hydrogenolysis/ring-opening activity followed the order: CAT1>CAT2>CAT3. The catalytic activity improved significantly upon alloying Rh with Pd (1:2 as atomic ratio), although the thio-tolerance remained low.