One-step oxidative-adsorptive desulfurization of DBT on simulated solar light-driven nano photocatalyst of MoS2-C3N4-BiOBr @MCM-41

Using a catalyst-adsorbent for simultaneous oxidation and adsorption of sulphuric compounds in liquid fuels is an effective and economical way. Thus in this paper, the core-shell MoS2-C3N4-BiOBr@MCM-41 photocatalyst-adsorbents with different percentages of MoS2 (1, 3, and 5 wt%) were prepared and used in a one-step photo oxidative-adsorptive desulfurization under simulated solar light. The samples were characterized by XRD, FESEM, FTIR, EDX, BET-BJH, TEM, UV-Vis DRS, and PL analyses. The results indicated that the final C/C0 decreased from 0.42 to 0.016 with increasing the MoS2 percentage (98.4% conversion). Despite the lowest surface area (845 m2/g) and the broad bandgap energy (2.8 eV), the sample with 5 wt% of MoS2 illustrated the most degree of desulfurization due to strong interaction between components, the highest coverage of MCM-41 with active phases, high population of structural defects, high capability of light absorption and low recombination rate of charge carriers. GC-MS analysis indicated no DBT, DBTO or DBTO2 in the treated fuel. However, the presence of DBTO2 on the surface of the photocatalyst was confirmed that reveals the successful one-step oxidative-adsorptive desulfurization on the MoS2-C3N4-BiOBr@MCM-41. The adsorption mechanism was consistent with the pseudo-second-order kinetics, indicating that the rate-limiting step was chemical adsorption. Moreover, selectivity evaluations showed that while MoS2-C3N4-BiOBr@MCM-41 photocatalyst had high activity in the desulfurization of DBT, its affinity for adsorption and photocatalytic oxidation of non-sulfur aromatic compounds such as benzene, xylene and toluene was very low. (c) 2022 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.

Automated summary

The study investigated the effectiveness and economy of using a catalyst-adsorbent for simultaneous oxidation and adsorption of sulphuric compounds in liquid fuels. The results showed that the sample with 5% MoS2 exhibited the highest degree of desulfurization.