Catalytic oxidative desulfurization of model and real diesel over a molybdenum anchored metal-organic framework

摘要

In this work, we report the catalytic performance of a MoO2Cl2 anchored metal-organic framework, Mo@COMOC-4, in the oxidative desulfurization (ODS) process on a continuous fixed-bed reactor. Mo@COMOC-4 was examined as a catalyst in the oxidation of model oils containing dibenzothiophene (DBT), benzothiophene (BT) or 4,6-dimethyldibenzothiophene (4,6-DMDBT). In a 50-h ODS reaction of DBT at 70 degrees C, with tert-butyl hydroperoxide (TBHP) as the oxidant, a constant high DBT conversion of nearly 80% was observed along with a high oxidant utility of over 85%, where DBT was converted rapidly into DBT sulfone. XRD and ICP analysis show that the structure of Mo@COMOC-4 was well preserved, with no significant leaching of Mo species. In addition, Mo@COMOC-4 can also oxidize a hydrogenated diesel oil, and 74% sulfur removal efficiency was achieved, with an extraction recovery of 92.5% after acetonitrile extraction. Spectroscopic characterization confirmed the formation of a molybdenum peroxide complex from MoO2Cl2 under TBHP treatment, a plausible catalytic process was proposed based on the experiment evidence as well as FT-IR and FT-FIR characterization results.