Engineering a Local Hydrophilic Environment in Fuel Oil for Efficient Oxidative Desulfurization with Minimum H₂O₂ Oxidant

Abstract

Oxidative desulfurization (ODS) using H 2 O 2 oxidant has emerged as a viable carbon-neutral way to produce premium-grade sulfur-free fuels, yet it currently suffers from overconsumption of oxidants and low efficiency for the immiscibility and high interfacial tension of water and oil. Here, we report efficient ODS using minimal H 2 O 2 oxidant without phase transfer agents. This is achieved by introducing organic modifiers (for example, etidronic acid (EA)) on molybdenum oxides anchored carbon nanotubes to dynamically activate Mo active sites and capture H 2 O 2 molecules. Such in situ generated local hydrophilicity depends on the electron-donating and hydrophilic −OH functional groups in EA, which can not only endow Mo active sites with high electron density for chemisorption of H 2 O 2 but also ensure the sufficient supply of H 2 O 2 . Combined with the substrate enrichment effect of hydrophobic porous carbon to sulfur contaminants, the efficient ODS reaction occurs at the solid−water−oil three-phase interface. The complete desulfurization was achieved within 10 min at 40 °C with an O/S ratio of 1, surpassing the optimum in the literature. This work unveils an avenue to improve ODS activity by harnessing the local reaction environment.

In situ encapsulation of ultrasmall MoO3 nanoparticles into beta zeolite for oxidative desulfurization

“…Molybdenum oxide possesses abundant unsaturated coordinated active sites, which are favorable for activating oxidants to generate electrophilic reaction intermediates. 21–23 Thus, different MoO 3 -based heterogeneous catalysts, for instance, MoO 3 /Al 2 O 3 , 24 MoO 3 /SiO 2 , 25,26 MoO 3 /MCM-41, 22,27 MoO 3 /SAPO-11, 28 and Mo/Co(OH) 2 , 3 have been extensively applied in catalytic ODS. However, an inferior productivity, defined as the activity per catalyst mass, and reaction rate are observed for low MoO 3 loadings, while high MoO 3 contents can easily cause agglomeration, thereby decreasing the utilization efficiency of Mo atoms.…”

Phosphotungstic-Acid-Based Ionic Liquid Catalyst for Efficient Photocatalytic Oxidative Desulfurization under Visible Light

“…T he combustion of sulfides existing in diesel can generate harmful production of sulfur oxides (SO x ), and mass emissions of sulfur oxides may result in serious environmental pollution, critically threaten ecosystems and human health. 1,2 Therefore, desulfurization of diesel fuels has become one of the most important issues that needs to be solved in the world. 3,4 To reduce the sulfur concentration below 10 ppm, hydrodesulfurization (HDS) technology is currently adopted in the petroleum refining industry.…”

“…The combustion of sulfides existing in diesel can generate harmful production of sulfur oxides (SO x ), and mass emissions of sulfur oxides may result in serious environmental pollution, critically threaten ecosystems and human health. , Therefore, desulfurization of diesel fuels has become one of the most important issues that needs to be solved in the world. , To reduce the sulfur concentration below 10 ppm, hydrodesulfurization (HDS) technology is currently adopted in the petroleum refining industry . However, for refractory aromatic sulfides, including dibenzothiophene (DBT), 4-methyldibenzothiophene (4-MDBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), etc., the HDS process requires harsh operating conditions, for instance, high hydrogen consumption and high temperature and pressure .…”