Effect of Lanthanum Doping on the reactivity of unsupported CoMoS2 catalysts

Abstract

Highlights:  A triphasic La-Co-Mo sulfide HDS catalyst was successfully synthesized using solvothermal synthesis  LaCoMoS2 showed enhanced activity over CoMoS2 catalysts.  The LaCoMoS2 activity as improved with increasing La doping  LaCoMoS2 showed less carbon than CoMoS2 after once catalytic cycle.  The La doping of the CMoS2 catalyst led to improvement in the direct desulfurization pathway.

The Application of Transition Metal Sulfide Nanomaterials and Their Composite Nanomaterials in the Electrocatalytic Reduction of CO2: A Review

“…The vapor pressure of water becomes a limiting factor and alterative solvents are to be explored for high temperature syntheses. In addition, the solvothermal process allows for the control of the phase, particle size, and morphology [124][125][126][127][128][129][130][131][132][133][134][135].…”

“…The authors successfully synthesized CdS nanowires at 180 • C, with diameters of 25 nm and lengths into the µm ranges, which showed controlled synthesis of CdS nanomaterials. Valdes et al on the other hand, synthesized nanosized CoMoS 2 doped with La ions for the desulfurization of fuels [135]. The authors prepared a CoMoS 4 precursor which was doped with different amounts of La ions to replace Co atoms from 5 to 25%.…”

Effect of Sodium on Ni-Promoted MoS2Catalyst for Hydrodesulfurization Reaction: Combined Experimental and Simulation Study

“…Hydrodesulfurization (HDS) is one of the most important catalytic processes in the petroleum industry to remove sulfur from organosulfur molecules such as dibenzothiophene (DBT), 2,8-dimethyldibenzothiophene (2,8-DMDBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) from crude feed. , The most widely used catalysts in the HDS process are Al 2 O 3 -supported MoS 2 catalysts with Co or Ni as a promoter. − Ni or Co promoters are preferred (1) because they lower sulfur vacancy formation energy in MoS 2 due to weaker bond energies of Ni–S/Co–S compared to Mo–S bond and (2) because of easier dissociation of molecular hydrogen. , The activities of promoted catalysts are influenced by many factors such as type of support, , pore size, poisoning of catalyst by undesirable atoms during synthesis, − metal loading, and synergistic effect of dopants . Though most of the above influencing factors have been explored in detail, the effect of Na incorporation in Ni-promoted MoS 2 has not been investigated sufficiently despite the presence of a few reports. , In this regard, we would like to mention that the effects of other group IA (e.g., Li, K) and IIA (e.g.,Mg) metal dopants have been documented in the literature. − …”