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ISSN 0965 5441, Petroleum Chemistry, 2012, Vol. 52, No. 1, pp. 41–48. © Pleiades Publishing, Ltd., 2012. Original Russian Text © A.V. Mozhaev, P.A. Nikul’shin, Al.A. Pimerzin, V.V. Konovalov, A.A. Pimerzin, 2012, published in Neftekhimiya, 2012, Vol. 52, No. 1, pp. 45–53.

Activity of Co(Ni)MoS/Al2O3 Catalysts, Derived from Cobalt(Nickel) Salts of H6[Co2Mo10O38H4], in Hydrogenolysis ofThiophene and Hydrogen Treatment of Diesel Fraction
A. V. Mozhaeva, P. A. Nikul’shina, b, Al. A. Pimerzina, V. V. Konovalova, and A. A. Pimerzina
Samara State Technical University, Samara, Russia e mail: P.A.Nikulshin@gmail.com b Middle Volga Research Institute of Oil Refining, Novokuibyshevsk, Samara oblast, Russia
Received July 21, 2011
a

Abstract—Co(Ni)MoS/Al2O3 catalysts have been prepared fromammonium 10 dodecamolybdodicobaltate (NH4)6[Co2Mo10O38H4] (further, Co2Mo10HPC) and cobalt(nickel) salts of 10 dodecamolybdodicobaltic acid H6[Co2Mo10O38H4] (hereinafter, Co2Mo10HPA). It has been found that a high activity of the Co(Ni)3– Co2Mo10HPA/Al2O3 catalysts in the hydrodesulfurization and hydrogenation reactions is due to the forma tion of a nanostructured type II CoMoS phase via thecontact of the metals (Mo and Co(Ni)) at the molecular level. The use of Ni as a copromoter in the Ni3–Co2Mo10HPA/Al2O3 catalyst leads to a simultaneous increase, compared with Co3–Co2Mo10HPA/Al2O3, in the linear size of nanoparticles and the number of MoS2 layers in the packing of active phase. The nature of the promoter X has a substantial effect on the prop erties of X3Co2Mo10HPC/Al2O3 catalysts.It has been found that the catalysts with X = Co exhibit the highest activity in the hydrodesulfurization reactions and those with X = Ni, in hydrogenation reactions. DOI: 10.1134/S0965544112010070

The properties of supported catalysts, in particular, catalysts, hydrotreating catalysts of the Co(Ni)MoS/Al2О3 type depend on the morphology (size and structure) of the active phase. The choice ofcompounds involved in the formation of the active phase can determine the catalyst activity. A line of cur rent importance in the synthesis of modern sulfide cat alysts for hydrotreating is the use as a precursor of het eropoly compounds (HPCs), inorganic coordination compounds formed by Mo and/or W atoms (ligand environment) and central heteroatoms (coordination centers) [1–12]. For example,Cabello et al. [3] pro posed HPCs of Anderson structure [X(OH)6Mo6O18]n– to be used for preparing the oxide precursor. Earlier studies [4] showed that the spatial proximity of Mo atoms with promoter atoms is a criterion for achieving a high activity by sulfide hydrotreating catalysts. In this case, the simultaneous presence of Mo and Co(Ni) in the structure of the heteropoly anion can preclude theformation of inactive spinels (Со(Ni)Al2O4) and ensures the necessary contact of the metals for generation of the nanosized active Co(Ni)MoS phase. Later, Cabello et al. [5] proposed to use ammonium decamolybdodicobaltate(III) (NH4)6[Co2Mo10O38H4] (Со2Мо10HPC), the dimer of the Anderson heteropoly anion (HPA) [Co(OH)6Mo6O18]3– (СоМо6HPC), for synthesizing a hydrotreating catalyst. The catalyst
41obtained on the basis of this HPC showed a higher cat alytic activity than samples synthesized with the use of both traditional precursors (ammonium paramolybdate (APM) and cobalt nitrate) and СоМо6HPC. The use of HPC with Anderson structure can sig nificantly increase the activity of hydrotreating cata lysts [2, 12] owing to the uniform distribution of the heteropoly anion on the support surface[3, 6], preser vation of the HPA structure in the temperature range of interest [7, 8], high acidity, and the ease of regener ation [9⎯11]. In this structure, the promoter atoms are located within the HPA, i.e., are linked to the Mo atoms via oxygen bridges, which leads to their selective fixing on the molybdenum sulfide edges to form the CoMoS phase during catalyst sulfiding [13]. The nature of...