Co-ZIF-67 encapsulated phosphomolybdic acid as a hybrid catalyst for deep oxidative desulfurization. Issue 6 (December 2021)

• Record Type: Journal Article
• Authors: Jafarinasab, Mitra; Akbari, Azam
• Is Part Of: Journal of environmental chemical engineering. Volume 9:Issue 6(2021)
• Publication Date: 2021-12
• Subjects: Oxidative desulfurization -- ZIF -- HPMo -- Model fuel -- Hybrid catalyst; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.106472
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: The introduction of an attractive catalyst for deep oxidative desulfurization (ODS) is a key factor in this process development. The combination of phosphomolybdic acid (HPMo) and a metal organic framework (Co-ZIF 67) in this work provided a new solid catalyst (named HPMo@Co-ZIF-67) for the selective and efficient removal of dibezothiophenes (DBTs) from fuels. A facile in situ strategy called battle around ship (BAS) was utilized to encapsulate HPMo active sites into the synthesized Co-ZIF-67 nanocrystals with a large surface area, stable structure, and defected sites. The prepared bimetallic HPMo@Co-ZIF-67 composite was used for the catalytic oxidative desulfurization (ODS) of bulky DBT from model fuel using TBHP oxidant. The successful incorporation of HPMo into Co-ZIF-67 and the suitable structure of the obtained composite have been verified by different characterization methods, including XRD, SEM, TEM, FT-IR, BET, BJH, and N2 adsorption-desorption. The ultra-deep desulfurization efficiency of 98% was obtained at T = 70 °C once 40 wt% HPMo loading was introduced. The synergetic effects of uniformly dispersed unsaturated Co ions and Mo contributed to the high ODS performance of the catalyst. A kinetic study was also undertaken, and a possible mechanism was suggested. The recyclability experiments were performed using the washing and heat treatment of the used catalyst. Only a 5% loss in the catalyst performance appeared after five consecutive ODS cycles. The catalyst structure also remained unchanged after five cycles, and no substantial HPMo leaching was detected during the ODS treatment. Graphical Abstract: ga1 Highlights: HPMo/Co-ZIF-67 composite was successfully prepared via BAS method at room temperature. The introduced hybrid catalyst was applied for ODS of model fuel for the first time. A high DBT removal efficiency of 98% under the optimal conditions was obtained. A significant high surface area, stability and regeneration ability was resulted. No important HPMo leakage during ODS of model fuel was appeared.