Production and testing of mahua oil–based biodiesel synthesized through heterogeneous catalyst using experimental and numerical method

A two-step treatment  of mahua oil was conducted to synthesize mahua biodiesel using heterogeneous biomass-based catalyst derived from mahua shell. Mahua oil having higher free fatty acid (FFA) content (about 19%) was esterified to reduce the FFA content up to 1%. The esterification process was carried out using 200 mL mahua oil, 5:1 molar ratio (methanol:oil), and 2.25 weight% of H₂SO₄ at a temperature of 60 °C for 3 h. Post esterification, a set of 16 experiments were created using a Box–Behnken design (BBD)–based response surface methodology (RSM) approach to conduct the transesterification of the esterified oil. Molar ratio, catalyst loading, reaction temperature, and reaction time were the four input variables chosen for the design of experiments. The optimized conditions for maximum biodiesel yield (87.7%) were found to be 14.88 molar ratio, 3.578% catalyst loading, 69.7 °C reaction temperature, and 81.9 min reaction time. The Diesel RK engine simulation tool which was experimentally validated for baseline diesel fuel was used for numerical simulation of mahua biodiesel. The performance, combustion, and emission behavior of mahua biodiesel analyzed using numerical simulation presented the sustainability of mahua biodiesel as an alternate fuel.