Dibenzothiophene capture from model fuel by wild mustard stems derived activated carbon: kinetics and isothermal evaluations

Abstract

ABSTRACT Wild mustard stems (WMS) are exploited as a potential and priceless feedstock for activated carbon (AC) synthesis through the optimised ZnCl2 activation method. Thermal Gravimetric Analysis (TGA), surface area (BET), Field Emission Scanning Electron Microscopy (FESEM-EDX), X-ray diffraction (XRD), Fourier Transform Infra-Red spectroscopy (FTIR), and Boehm titration method have employed in identifying the AC. The as-obtained AC was applied in the desulphurisation of dibenzothiophene (DBT) from synthetic gasoline and commercial gasoline samples. A 96.02% as a maximum removal efficiency of DBT from model gasoline was obtained at 30°C for a contact time of 30 minutes using 25 mL of 200 mg/L DBT solution and 0.40 g of the AC. The adsorption data have analysed for their adsorption isotherms, and the consequences followed the following order: Langmuir model > Freundlich model> Temkin model. The kinetics studies revealed that the pseudo-second-order kinetic model obeyed best the adsorption data. The desulphurisation study of the commercial gasoline through applying the best adsorption conditions gave a removal efficiency of 50.22% compared to 96.02% for the model gasoline. In conclusion, the present investigation offers a cheap and potential feedstock to create AC as an adsorbent for both model and commercial gasoline fuel desulphurisation.