Liquid-phase hydrogenation of thiophenes on palladium sulfide catalysts

Palladium sulfide catalysts are active for the hydrogenation of thiophenes of different structure in hydrocarbons at 220-300 degrees C and 3.0-9.5 MPa. Thiophenes and benzothiophenes are close in reactivity. An increase in palladium sulfide concentration in the catalyst leads to an increase in the reaction rate per 1 g of the catalyst but has only a slight effect on the specific reaction rate of hydrogenation calculated per 1 g of Pd. The specific activity of palladium sulfide supported on aluminosilicate is one order of magnitude higher than that of PdS without a support and the catalysts supported on the aluminum oxide and carbon. The aluminosilicate-supported catalyst is also more selective.