In this study, calcium titanate nano-particles (CaTiO3 NPs) were synthesized through solution combustion synthesis (SCS) by using Ochrocarpus longifolius leaves extract as a novel fuel. The CaTiO3 NPs were successfully utilized in the biodiesel synthesis from dairy waste scum oil (DWSO) as a heterogeneous base catalyst. The synthesized CaTiO3 NPs were characterized by SEM, XRD, TEM, BET, FT-IR and CO2-TPD. Response surface methodology (RSM) in arrangement with central composite design (CCD) was utilized to determine the optimum conditions for biodiesel production by varying catalyst loading, molar ratio and reaction time. The maximum 97.7% yield of dairy waste scum oil methyl ester (DWSOME/biodiesel) was obtained for a molar ratio (methanol to DWSO) of 9:1, 1.80 wt% catalyst loading and 45 min reaction time with constant temperature (65 degrees C) and stirring speed (650 rpm). The CaTiO3 NPs shows a good catalytic stability up to five cycles with a low loss of yield. The kinetic study of biodiesel production fit well to pseudo-first order reaction. For transesterification reaction, the 35.56 kJ/mol of activation energy (Ea) was found. Finally, the DWSOME was characterized by H-1 NMR and the fuel properties were also determined and were in the range of ASTM standards. (C) 2019 Elsevier Ltd. All rights reserved.