Insight into the effect of non-stoichiometric sulfur on a NiMoS hydrodesulfurization catalyst

Abstract

The finding provides new insight into NiMoS model that there is a sulfur dynamic equilibrium between NiMoS edge and gas phase. Since the evolution of non-stoechiometric sulfur proceed rapidly at initial stage of hydrodesulfurization reaction, the sulfur dynamic equilibrium does not draw so much attention. The results indicate that excess sulfur on Ni-Mo-S edge can be reduced by hydrogen to form SH groups and release H2S, which lead to a low sulfur covered NiMoS edge and a significant increase of coordinatively unsaturated sites (CUS), resulting in an outstanding HDS activity. Except for elucidating the effect of non-stoechiometric sulfur on NiMoS structure, a relationship among H2S partial pressure -Sx -HDS activity has been quantitatively studied. It is expected that these results will be used to deepen the understanding of HDS reaction over promoted MoS2 catalysts, as well as to guide the research of ultra-deep HDS of fuel oils.

Nanosheet-structured K–Co–MoS2 catalyst for the higher alcohol synthesis from syngas: Synthesis and activation

“…Furthermore, the formation of SH groups also leads to a low sulfur-covered Co-Mo-S edge and a significant increase in coordinatively unsaturated site (CUS). The abundant CUS provides more Lewis acidity site, thus enhancing CO adsorption and improving the catalyst activity [36] . Consequently, the catalyst activated in pure H 2 shows higher activity, especially the C 2 + OH selectivity toward the higher alcohols synthesis.…”

Designing an Advanced Supercapattery Based on CuCo2S4@Ni−Mo−S Nanosheet Arrays

“…Recently, Ni−Mo−S (NMS) catalyst has been examined for hydrogen evolution reaction, resulting in outstanding robustness and amazing catalytic activity. Accordingly, NMS electrode is expected to be a satisfied electrode for SCs, due to its good catalytic activity and electrical conductivity …”

“…Accordingly, NMS electrode is expected to be a satisfied electrode for SCs, due to its good catalytic activity and electrical conductivity. [27,28] It has been proved that the electrochemical behavior of an electrode is affected by the morphology and structure of its materials. [29,30] Accordingly, scientists introduced different types of architectures such as nanowires, [31] nanosheets, [32] and nanotubes, [33] which reflected high Cs owing to their exclusive porous networks and remarkable surface area (SA).…”

Management of γ-Alumina with High-Efficient {111} External Surfaces for HDS Reactions

“…to the S 2s [31,34]. The atomic fraction for the sulfided phases of MoS2 is 88.3%, 87.2%, 85.0%, and 80.8% for NiMo/AN, NiMo/CA, NiMo/AH, and NiMo/AR catalysts, respectively.…”

“…An intermediate phase (Mo V 3d 5/2 ) were found to be located at 230.6 ± 0.2 eV, which can be identified as MoO x S y species. The peak centered at 226.0 eV is assigned to the S 2s [31,34]. The atomic fraction for the sulfided phases of MoS 2 is 88.3%, 87.2%, 85.0%, and 80.8% for NiMo/AN, NiMo/CA, NiMo/AH, and NiMo/AR catalysts, respectively.…”