A two-step so3h/icg catalyst synthesis for biodiesel production: optimization of sulfonation step via microwave irradiation

Abstract

Conventional heating, a common method used for heterogeneous solid acid catalyst synthesis unknowingly con-sumes massive time and energy. In this study, acid catalyst was prepared through sulfonation process of incom-plete carbonized glucose (ICG) via microwave-Assisted technique to shorten the heating time and energy consump-Tion. Optimization of the sulfonation process of ICG via microwave-Assisted was carried out. Four-factor-Three-level central composite design (CCD) was used to develop the design of experiments (DOE). Interaction between two factors was evaluated to determine the optimum process conditions. A quadratic model was proposed for pre-diction of biodiesel yield (Y) from palm fatty acid distillate (PFAD) and its conversion (C). The application of DOE successfully optimized the operating conditions for the two-step SO3H/ICG catalyst synthesis to be used for the es-Terification process. The optimized conditions of the best performing SO3H/ICG with maximum Y and C were at 7.5 minutes of reaction time, 159.5 mL of H2SO4 used, 671 rpm of stirring rate as well as 413.64 watt of power lev-el. At these optimum conditions the predicted yield percentage and conversion percentage were 94.01% and 91.89%, respectively, which experimentally verified the accuracy of the model. The utilization of sulfonated glucose solid acid catalyst via microwave-Assisted in biodiesel production has great potential towards sustainable and green method of synthesizing catalyst for biodiesel.