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In this study, Manganese oxide nanoparticles (MnO2NPs) are deposited over Zr-based UiO-66 molecular organic framework (MOF) resulting in MnO2/UiO-66 composite which is oxidized with NaClO for the catalytic oxidative desulfurization and denitrogenation of fuel oil. The as-synthesized composites were characterized via FE-SEM, EDX, BET, XPS and FT-IR techniques which confirmed the uniform deposition of MnO2NPs and resulted in increased surface area and average mesoporous volume of pristine UiO-66. Catalytic results showed that MnO2/UiO-66 oxidized 2000 ppm of DBT (347 ppm Sulfur) and pyridine (502.8 ppm Nitrogen) in 3 min at O/S and O/N of 4, 0.06 g/15 mL catalyst dose and 25 °C. The mechanism behind the super-fast and highly efficacious performance of MnO2/UiO-66 is the ideal synergy among Mn4+, Zr4+and NaClO species, which produced strong oxidizing •OH and •O2−radicals. Under the optimized reaction parameters, much higher removal of DBT and pyridine (100%) was achieved as compared to those of BT, 4,6-DMDBT, indole, and carbazole up to 6th cycles. This study provided important oxidant-catalyst system i.e. MnO2/UiO-66-NaClO for the highly efficacious, super-fast, and time and cost-effective alternative to the large scale oxidative desulfurization and denitrogenation of fuel oils.

Herein we report the fabrication of ternary system mixed matrix membranes based on polyvinyl acetate (PVAc) incorporated reduced graphene oxide (rGO) and CuO or Ag2O nanoparticles as filler in different weight ratios via non-solvent induced phase inversion separation method. The fabricated membranes were characterized for chemical composition porosity, pore distribution, surface roughness, thickness, water contact angle and mechanical strength. Scanning electron microscopy and atomic force microscopy analyses revealed that pure PVAc exhibited smooth and uniform surface while PVAc/rGO/Ag2O and PVAc/rGO/ACuO membranes possessed rough and uneven topography and higher surface porosity. PVAc/rGO/CuO and PVAc/rGo/Ag2O membranes exhibited total permeate flux of 1.60 × 10–2g/m2s and 1.28 × 10–2g/m2s corresponding to net removal of 99.9% and 98.0% respectively from model wastewater of Cr6+under the optimized experimental conditions. Interestingly, under these optimized conditions, PVAc/rGO/CuO membrane achieved Cr6+removal of 99.9% from anti-corrosive paint industrial wastewater (as real sample) with a flux of 1.90 × 10-2g/m2s, which was much higher than many state of the art membranes. The uptake of Cr6+from real solution was confirmed by EDX and AFM analysis of the post-separation membrane. The newly designed PVAc/rGO/CuO membrane, attributed to cost-effectiveness, environmental greenness, ease of syntheisis and high efficiency, can be envisioned of potential applications for the remediation of Cr6+and other similar pollutants from real industrial wastewater.