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The global interest in renewable combustibles has been seriously intensified nowadays, mainly due to worldwide energy crises; including high energy demand, pollution problems, instability and fluctuating oil price, reduction of the availability of fossil fuels, increasing energy subsidies and impact on the ecology.  Biodiesel are biofuels produced from biomass which are clean alternatives fuels. Biofuels synthesis from biomass is of interest because these biomasses are renewable, biodegradable, readily available and environmentally benign resources.  This work reports the results of the study of some chemical properties and analysis of biodiesel produced from Castor (CSO), Palm kernel (PKO) and Groundnut (GNO) oils. The biodiesel was produced by transesterifying refined oil samples (CSO, PKO and GNO) at 6:1 1-propanol to oil molar ratio in the presence of their various optimal catalyst weight earlier calculated (0.50 wt/v for CSO and PKO, and 0.40 wt/v for GNO) at 65oC for 60 minutes. The process for the production of biodiesel using an alkali (sodium hydroxide – NaOH) catalyzed method in a batch reactor was composed of glycerol separation steps (after each transesterification step) and an ester purification step. The following values were obtained  for CSO, PKO and GNO biodiesels: Saponification value 168.20, 204.50 and 180.08 mg KOH/g; acid value 0.44, 0.48 and 0.52 mg NaOH/g; iodine value 71.01, 12.11 and 74.05 g I2/g which were within  Biodiesel standards EN 14214(Europe) ASTM D 6751 (America) for Vehicles utilizing biodiesel. The infrared spectra results revealed the presence of major functional groups in the three oils, obviously hydroxyl (3445.51cm-1 for CSO, 3466.43 cm-1 for GNO and 3459.87 cm-1 for PKO); carbonyl (1746.70 cm-1 for CSO, 1744.95 cm-1 for GNO and 1746.67 cm-1); Olefinic (1652.01 cm-1 for CSO, 1652.71 cm-1 for GNO and 1644.83 cm-1 for PKO) and methylenic (2925.73 cm-1 for CSO, 2924.89 cm-1 for GNO and 2924.03 cm-1 for PKO). Generally, results obtained were within acceptable range set by various International Standards, showing promising sources for biodiesel production in Nigeria. Keywords: Biodiesel, Transesterification, Alkali-catalysis, Infrared, Renewable.