Desulphurisation of synthetic gasoline using nanocellulose crystals derived from waste biomass: adsorption performance, isotherms, kinetics, and thermodynamics

Abstract The desulphurisation of gasoline to the globally acceptable sulphur level is crucial for a cleaner environment. This study evaluated the adsorption performance of nanocellulose crystals, a novel adsorbent derived from renewable waste biomass, for desulphurising synthetic gasoline. The nanocellulose adsorbent was added to the synthetic gasoline and stirred under varying temperatures to assess sulphur removal and adsorption capacity. A High-Performance Liquid Chromatography was used to measure the sulphur concentrations. The surface morphology, elemental configurations, and chemical functionality results showed that sulphur compounds were adsorbed onto the nanocellulose crystals’ surface. The adsorption performance showed that both contact time and initial sulphur concentration contributed to increased sulphur removal. However, after the adsorbent mass increased beyond 0.6 g, the sulphur removal remained constant, and a temperature rise from 25 to 32.5 °C was advantageous for the sulphur removal. In addition, this study achieved up to 79.88% sulphur removal and 26.63 mg/g adsorption capacity under optimal conditions. The Freundlich isotherm model indicated multilayer adsorption, while the pseudo-second-order kinetic model provided the best fit for the experimental data. Also, the thermodynamic analysis revealed exothermic and spontaneous adsorption with decreased randomness. This study demonstrates that nanocellulose crystals offer a sustainable and efficient alternative for gasoline desulphurisation, with promising potential for industrial applications.