Effect of loading different transition metals W, Pt and Pd monolayers on quinoline hydrogenation and C–N bond cleavage over Mo2C(001)

Abstract

Nitrogen-containing compounds such as quinoline in coal-based crude oils cause environmental pollution in the course of application. Consequently, dealing with the nitrogen-containing compounds from coal-based crude oil is of paramount importance. The hydrogenation and CN bond cleavage mechanisms of quinoline on the active Mo-terminated over Mo2C(001) surface, as well as on surfaces doped with W, Pt and Pd monolayers, were examined employing the density functional theory (DFT) method. The Pd and Pt-doped catalysts exhibited higher hydrogenation activity. The catalytic efficiency is enhanced by the loading of different metals, particularly with d-band center further away from the Fermi energy level. Additionally, a novel CN bond cleavage mechanism for quinoline has been proposed. The new proposed mechanism is more conducive for the CN bond cleavage. After a thorough comparison, the Pd-loaded catalyst was identified as the most effective for quinoline hydrogenation and CN bond cleavage.