Fabrication of dual-mesoporous silica by triblock copolymers and metal-based ionic liquid: efficient and durable catalyst for oxidative desulfurization in fuel

Abstract

Dual-mesoporous silica was synthesized using the ionic liquid [C₁₆mim]₃PMo₁₂O₄₀ (1-hexadecyl-3-methylimidazolium phosphomolybdate) and the triblock copolymer P123 as co-templates. In this strategy, the ionic liquid [C₁₆mim]₃PMo₁₂O₄₀ was not only employed as the template, but also provided the metal source. The obtained catalysts were characterized by FTIR, Raman, XRD, XPS, N₂ adsorption–desorption and utilized as catalysts to remove organic sulfur compounds from the model oil. The results demonstrated that compared with single channel silica, the catalysts with two uniform sets of mesopores showed higher catalytic performance for oxidative desulfurization. Dibenzothiophene (DBT) could be completely removed at 60 °C in 50 min. With regard to the refractory sulfur compound 4,6-dimethyldibenzothiophene (4,6-DMDBT), deep desulfurization could also be achieved. Moreover, the dual-mesoporous catalyst exhibited outstanding stability. It could be recycled for at least seven times without any activity decrease.