Study of the Hydrogen Activation Reaction on Nanosized Mo[S.sub.2] Particles under Hydroconversion Conditions

• Published in: Petroleum chemistry 2018-08, Vol.58 (8), p.630
• Main Authors: Kadiev, Kh.M, Gyul'maliev, A.M, Kadieva, M.Kh, Khadzhiev, S.N
• Format: Article
• Language: English
• Subjects: Analysis; Density functional theory; Hydrogen; Molybdenum; Molybdenum compounds
• ISSN: 0965-5441
• DOI: 10.1134/S0965544118080108

The mechanism of activation of a hydrogen molecule upon interaction with the surface of nanosized particles of the Mo[S.sub.2] hydroconversion catalyst has been modeled using a quantum-chemical method of the density functional theory (DFT) with the hybrid functional B3LYP/dgdzvp in the cluster approximation. Two clusters, [Mo.sub.2][S.sub.4] and [Mo.sub.3][S.sub.6], have been considered as structural models of nanosized catalyst particles. It has been shown that the primary event of interaction of molecular [H.sub.2] with the catalyst surface is the chemisorption of hydrogen atoms on the molybdenum atom with H--H bond breaking. The local minima of the total electronic energy of the complexes in the chemisorption of hydrogen atoms on Mo and S atoms and the energy of the transition state between local minima have been found. It has been established that the stability of the complexes [[Mo.sub.3][S.sub.6]***[H.sub.2]] varies in the order: [***Mo[H.sub.2]] > [(S)H***(S)H] > [(Mo)H***(S)H] > [(Mo)H***(Mo)H] > [***S[H.sub.2]]. Keywords: hydroconversion, nanoparticles, molybdenum disulfide, hydrogen, chemisorption, quantumchemical Analysis DOI: 10.1134/S0965544118080108