Process optimization and kinetic modeling of biodiesel production using non-edible Madhuca indica oil

•Non-edible mahua oil is utilized for biodiesel production.•RSM was used to optimize the transesterification process variables.•Catalyst, methanol and temperature had significant effect on mahua biodiesel yield.•Biodiesel production follows first-order kinetics.•Mahua biodiesel satisfied the ASTM standards. Optimization and kinetic modeling of biodiesel production from non-edible Madhuca indica oil were investigated in this study. Type of catalyst, catalyst concentration, methanol amount, and reaction temperature were optimized by the univariate method. KOH was found as a better catalyst for conversion of mahua oil to biodiesel. Response surface methodology (RSM) was employed to determine the optimal level of KOH (%), methanol amount (v/v), temperature (°C) and time (min). Maximum biodiesel yield of 91.76% was predicted at the optimal level of KOH as catalyst (1.5%), methanol amount (0.32% v/v), temperature (60°C) and time (90min). Biodiesel yield (88.71%) was obtained in the validation experiments and fitted 96.6% with the RSM predicted results. Kinetic studies were performed at different temperatures and observed that the conversion of mahua oil to biodiesel follows the first order reaction. The kinetic rate constants and activation energy were calculated. The physiochemical properties of mahua biodiesel were determined using standard methods and the mahua biodiesel properties are in accordance with the ASTM D6751 standards.