1In this study, a novel sulfonated carbon catalyst has been synthesized via one-step 2 hydrothermal carbonization of cyclodextrin, hydroxyethylsulfonic acid and citric acid. The 3 ultrasonic assisted biodiesel production from waste cooking oil in the existence of catalyst 4 was investigated. The novel catalyst was characterized by BET, XRD, PSD, SEM-EDS, 5 TGA, FT-IR, XPS and TPD. The catalyst exhibited a high acidity up to 1.87 mmol/g. 2 k 6 factorial and Box-Behnken designs were applied to find the optimum conditions obtaining a 7 maximum fatty acid methyl ester (FAME) yield. The result of the optimization implies that 8 catalyst loading of 11.5 wt.%, reaction time of 8.8 min and reaction temperature of 117 °C 9 provide a maximum FAME yield up to 90.8% in the ultrasonic assisted biodiesel production.
10The reusability of catalyst was studied for 4 cycles under optimum conditions and the results 11 found that regenerated catalyst can be reused without any serious reduction of FAME yield.
12Kinetic studies showed that the reaction followed the first order reaction with activation 13 energy of 11.64 kJ/mol. 14