Ultrafine W2C well-dispersed on N-doped graphene: Extraordinary catalyst for ultrafast oxidative desulfurization of high sulfur liquid fuels

A ternary nanocomposite comprising phosphotungstic acid (PW12), polyethyleneimine (PEI), and graphene oxide (GO), i.e., PW12-PEI/GO, was developed as a precursor to obtain the W2C/N-rGO catalyst upon in-situ carbonization. W2C/N-rGO was applied in the deep oxidative desulfurization (ODS) of liquid fuel, and exhibited extraordinary performance due to the ultrafine W2C nanoparticles (similar to 3-5 nm) evenly dispersed on N-rGO and the electron-donating effect of N-rGO on W2C. 4000 ppm of DBT in model oil could be completely removed within only 10 min with a remarkably high turnover frequency (168 h(-1)) and the lower activation energy (30.9 kJ.mol(-1)). Radical experiments and density functional theory calculations indicate that the ODS reaction proceeds mainly via a HO center dot radical mechanism. Moreover, W2C/N-rGO could be recycled for 6 successive cycles with no obvious loss of performance.

Automated summary

The ternary nanocomposite PW12-PEI/GO was developed as a precursor for the W2C/N-rGO catalyst, which exhibited extraordinary performance in deep oxidative desulfurization (ODS) of liquid fuel, particularly in the complete removal of DBT with high turnover frequency and low activation energy. Radical experiments and density functional theory calculations suggest that the ODS reaction mainly proceeds via a HO center dot radical mechanism. Furthermore, the W2C/N-rGO catalyst showed no obvious loss of performance after 6 cycles of recycling.