The main objective of the present paper comprises the investigation of biodiesel production from low-cost feedstock such as lard oil and waste cooking oil (WCO) using Sr-Al double oxides. Nanocatalyst was characterised FTIR, XRD, SEM, TEM, BET and XPS. The Sr:Al with 3:1 M ratio showed the best catalytic activity in the conversion of both oils to fatty acid methyl ester. The effect of acetone and tetrahydrofuran (THF) as a co-solvent for transesterification were compared and the best result was obtained with 5% THF. The mutual effect of the nanocatalyst and co-solvent on biodiesel production was investigated. The characterisation of biodiesel synthesised from lard oil and WCO was performed with GC-MS, H-1 and C-13 NMR. Moreover, the optimum reaction parameters for transesterification reaction was analysed and the yield was determined by H-1 NMR. The maximum yield of 99.7% and 99.4% of lard oil methyl ester and WCO biodiesel were observed with a 0.9 wt% catalyst amount, 1:5.5 oil to methanol ratio in a reaction time of 45 min at 50 degrees C and 60 degrees C, respectively. The properties of biodiesel from lard oil and WCO were determined by the EN 14214 method. The regeneration, characterisation and reusability of regenerated catalyst was observed. (C) 2019 Elsevier Ltd. All rights reserved.