Cu(Ⅰ) anchoring in MOF-808 as a stable catalyst in ultra-deep oxidation desulfurization

Abstract

Oxidative desulfurization (ODS) is a promising technique for obtaining clean fuel. Designing and researching zirconium-based metal–organic frameworks (Zr-MOFs) with bimetallic catalytic sites are encouraging for its further development. In this study, Cu(Ⅰ)-MOF-808 was successfully synthesized through anchoring Cu+ in MOF-808. Pyridine infrared spectrum (Py-IR) and NH3 temperature programmed desorption (NH3-TPD) confirmed that Lewis (L) acid sites existed in the synthesized material. Cu(Ⅰ)-MOF-808 was applied into the ODS reaction, during the reaction process, L acid sites adsorbed sulfide, Cu+ sustainably provided electron to H2O2 to formed into •OH, with the synergistic effect of L acid sites and Cu+, 99.9 % of the dibenzothiophene was oxidated to dibenzothiophene sulfone in 120 min. In addition, the cyclic experiment indicated that the ODS performance of Cu(Ⅰ)-MOF-808 was maintained at 99.2 % after 12 times recycling. Powder X-ray diffraction (PXRD) spectra indicated the framework structure of the reused catalyst was stable, inductively coupled plasma optical emission spectrometer (ICP-OES) result displayed no metal ions (Zr, Cu) leaching after the ODS reaction, which also proved the catalytic stability of the Cu(Ⅰ)-MOF-808.