Synthesis of N,O-Doped Porous Graphene from Petroleum Coke for Deep Oxidative Desulfurization of Fuel

Abstract

Efficient metal-free carbon-based catalysts are of particular interest due to their unique electronic structure and compositional variability. Herein, petroleum-coke-based N,O-doped porous graphene (PG) was prepared as a preferred alternative to metal catalysts for catalytic oxidative reaction. Such a high specific surface area and heteroatom-rich structure promote high exposure of active sites, regulating the electron delocalization of materials effectively. In addition, the synergistic effect between N-doped and oxygen-containing functional groups is beneficial for the catalytic performance. As such, when employing the active PG as catalyst for the catalytic oxidative desulfurization (ODS), aromatic sulfur-containing compounds would be oxidized effectively and the sulfur removal in real diesel reached 84%. This work develops a facile approach for preparing heteroatoms co-doped porous graphene for aerobic catalytic ODS as well as an effective design idea for high value-added utilization of petroleum coke.

A current overview of the oxidative desulfurization of fuels utilizing heat and solar light: from materials design to catalysis for clean energy

“…To address environmental friendliness and sustainability, He et al reported a creative and sustainable technique to derive N,O-doped porous graphene (N,O-PG) from the coke waste of the petroleum refinery industry. 199 Basically, a ball-milling process was first conducted in the presence of coke and urea, accompanied by annealing to activate the catalyst and decompose the layered structure graphene into an ultrathin nanosheet structure (Fig. 17a).…”

“…203 First, the activation of H 2 O 2 was stimulated by the carboxyl groups at the edge of GO. After DBT oxidation, the produced polar DBT sulfone strongly chemisorbed on the basal plane of GO, which contained hydroxyl groups, via hydrogen bonding and p-p interactions, thus eliminating the need for solvent to separate 199 Copyright 2019, American Chemical Society. (c) Proposed route for the oxidation of DBT with H 2 O 2 by GO with a SEM image of GO.…”

“…(b) Catalytic activity of N,O-doped porous graphene and commercial graphite in removing DBT using O 2 at 120 1C. Reprinted with permission 199. Copyright 2019, American Chemical Society.…”

Carbon-Based Materials for Oxidative Desulfurization and Denitrogenation of Fuels: A Review

“…The activity of the carbon material can be ascribed to the presence of defect sites on its surface, its developed surface area, or the presence of surface groups. Here, we propose the mechanism displayed in Figure 10 for the ODS of sulfur-containing compounds according to different proposals in the oxidation activity of carbon catalysts [130,131].…”

“…This interaction between acidic groups and S atoms increases the physisorption of S compounds in the AC structure [133]. [131] studied the influence of doping GO with nitrogen and oxygen for the aerobic ODS of various sulfur compounds. They compared two GO samples.…”