Satheesh, K.JagadeeshBabu, P.E.Saidutta, M.B.2026-02-052015Energy Sources, Part A: Recovery, Utilization and Environmental Effects, 2015, 37, 1, pp. 92-10015567036https://doi.org/10.1080/15567036.2013.875080https://idr.nitk.ac.in/handle/123456789/26418Free fatty acid of waste cooking oil was reduced through esterification using Indian-190 and then transesterified using AmberliteIRA-900 to produce biodiesel. Maximum conversion of 93.69% was observed during esterification at optimized conditions (temperature: 337 K; duration: 4 h; methanol:oil: 20:1; catalyst: 8 wt%). Biodiesel conversion of 98.69% was observed with a yield of 80% through transesterification. Temperature dependence was analyzed using the Langmuir-Hinshelwood model. Activation energy of 134.952 kJ/mol and a frequency factor of 5.49 × 1015 min-1 were observed. Thermodynamic parameters were determined using the Vant Hoff plot. Properties of biodiesel were found to be within ASTM standard. Reusability of Indion-190 was analyzed for five cycles, and found to be satisfactory. © © © Taylor & Francis Group, LLC.Activation energyBiodieselEnzyme kineticsEstersFatty acidsReusabilityTemperature distributionAmberliteIRA-900Biodiesel productionIndion-190Langmuir-Hinshelwood modelsOptimized conditionsTemperature dependenceThermodynamic parameterWaste cooking oilOils and fats