Hydrotreating Catalyst Design and Performance

Hydrotreating catalysts are essential for removing sulphur, nitrogen and metals from petroleum feedstocks, enabling the production of cleaner fuels and compliance with stringent environmental regulations. Predominantly based on sulphided transition metal phases—most notably molybdenum disulphide promoted with cobalt or nickel and supported on alumina—these catalysts rely on finely tuned active sites at the edges of nanometre-scale particles. Key design parameters include the dispersion and stacking of MoS₂ layers, the nature and distribution of promoter atoms, the acidity and porosity of the support, and the degree of sulphidation under reaction conditions. Advances in atomic‐scale characterisation have revealed how structure and composition evolve under high–temperature, high–pressure hydrogen atmospheres, guiding the synthesis of materials with optimised coordinatively unsaturated sites and enhanced resistance to deactivation. Emerging strategies focus on single-atom promotion, hierarchical supports and theoretical modelling to drive ultra-deep desulfurisation, bio-oil upgrading and hydrogen economy applications on a global scale.

Research from Nature Portfolio

Recent studies have used high-pressure scanning tunnelling microscopy to observe MoS₂ nanoislands under realistic hydrotreating conditions, revealing that active edge sites dynamically adapt their sulphur, hydrogen and hydrocarbon coverages. These insights demonstrate that the working catalyst surface is neither fully sulphur-covered nor fully reduced, but instead maintains a balanced mix of intermediates that govern reactivity. Complementary atom-resolved imaging combined with density functional theory has shown that not all sulphur-vacancy sites are equally active: vacancies at particle corners facilitate thiophene adsorption, whereas vacancies along straight edges require a concerted displacement mechanism to become reactive. In another work, direct visualisation of Co-promoted MoS₂ clusters under reducing conditions quantified how promoter atoms influence edge termination and surface acidity, providing a structural blueprint for tailoring the ratio of sulphur to hydrogen at the catalytic perimeter.

Hydrotreating Catalyst Design and Performance publication trend

The graph below shows the total number of articles in hydrotreating catalyst design and performance across all publications each year (not limited to Nature Index journals).

Technical terms

Hydrodesulfurization (HDS): A hydrogen-assisted catalytic process for removing sulphur from petroleum fractions.

Coordinatively Unsaturated Site (CUS): A metal atom at the catalyst surface with incomplete coordination, serving as an active centre for reactant adsorption and bond activation.

Promoter: An added element (e.g. cobalt, nickel, platinum) that enhances the activity or selectivity of the primary catalytic phase.

Support: A high-surface-area material (commonly aluminium oxide) that disperses and stabilises the active sulphide phase.

Sulphur-vacancy site: A missing sulphur atom in the MoS₂ lattice that creates an undercoordinated metal centre capable of binding reactants.

References

1. Visualizing hydrogen-induced reshaping and edge activation in MoS2 and Co-promoted MoS2 catalyst clusters. Nature Communications (2018).
2. Recent Insights in Transition Metal Sulfide Hydrodesulfurization Catalysts for the Production of Ultra Low Sulfur Diesel: A Short Review. Catalysts (2019).
3. In situ observations of an active MoS2 model hydrodesulfurization catalyst. Nature Communications (2019).
4. Site-dependent reactivity of MoS2 nanoparticles in hydrodesulfurization of thiophene. Nature Communications (2020).
5. Single-atom Pt promotion of industrial Co-Mo-S catalysts for ultra-deep hydrodesulfurization. Journal of Catalysis (2021).
6. Hierarchically porous Beta/SBA-16 with different silica-alumina ratios and the hydrodesulfurization performances of DBT and 4,6-DMDBT. Petroleum Science (2022).