Rapid Oxidation of Sulfur Compounds: An Oscillatory Helical Baffled Reactor and a Nanocatalyst for Enhancing the ODS Process

The production of clean fuel with stringent limits on harmful contaminants is one of the petroleum refinery industry’s main goals for improving environmental conditions and being eco-friendly. Iron oxide (Fe2O3) loading over composite support (γ-Al2O3–TiO2) was synthesized and evaluated for oxidative desulfurization (ODS) via the incipient wetness impregnation (IWI) procedure. To prolong the lifetime of the nanocatalyst, it was coated with a newly developed manganese compound via IWI technology to suppress substantial deactivation. The composite support, uncoated nanocatalyst, and coated nanocatalyst were tested by different methods of characterization: BET, XRD, FT-IR, FESEM-EDX, mapping, and TEM. The XRD and FTIR results indicated that the composite nanosupport was designed successfully. The FESEM-EDX results indicated high Fe2O3 dispersions on the composite nanosupport, and the TEM result represented a good layer of Mn-coated material over the nanocatalyst. The ODS in a newly oscillatory helical baffled reactor (OHBR pilot plant) is utilized to test the performance of the prepared nanocatalysts. Oxidative desulfurization utilized peracetic acid as an oxidant and moderate operating conditions. From the experimental results, it was observed that the optimal desulfurization was 98.42% in the best conditions (amplitude of oscillation = 8 mm, frequency of oscillation = 2 Hz, and oxidation time = 9 min) with an uncoated nanocatalyst. With the coated nanocatalyst, the optimal removal was 96.57% under the same conditions. The uncoated nanocatalyst exhibited good reusability, with sulfur removal decreasing from 98.42% to 87.23% after five consecutive cycles.