Process Optimization for Catalytic Oxidation of Dibenzothiophene over UiO-66-NH₂ by Using a Response Surface...

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Chemistry

Background:

• Dibenzothiophene (DBT) is a persistent sulfur pollutant in fuels.
• Oxidative desulfurization (ODS) is a promising method for removing DBT.
• Metal-organic frameworks (MOFs) offer tunable catalytic properties for ODS.

Purpose of the Study:

• To investigate the catalytic performance of UiO-66-NH2 MOF for DBT oxidative desulfurization.
• To optimize reaction conditions using response surface methodology (RSM).
• To assess the catalyst's reusability in ODS.

Main Methods:

• Solvothermal synthesis and characterization of UiO-66-NH2 MOF (XRD, FTIR, NMR, SEM, TGA, MP-AES).
• Experimental design using Central Composite Design (CCD) within RSM.
• Optimization of temperature, oxidant-to-sulfur (O/S), and catalyst-to-sulfur (C/S) ratios.

Main Results:

• Optimal conditions: 72.6 °C, O/S ratio of 1.62, C/S ratio of 12.1.
• Achieved 89.7% DBT removal with a desirability score of 0.938.
• Temperature was identified as the most significant factor affecting DBT removal.

Conclusions:

• UiO-66-NH2 MOF is an effective catalyst for DBT oxidative desulfurization.
• RSM successfully optimized the ODS process.
• The catalyst showed potential but exhibited a gradual activity loss over four reuse cycles.