The effects of operating parameters for the esterification of free fatty acids with butanol in the presence of sulfuric acid were studied. Experiments were carried out at catalyst loadings of 0.5, 1, and 7 wt% relative to reaction mixture, butanol/free fatty acids mole ratios of 1, 2, and 6 and the temperatures of 358, 368, and 378 K. Increase in reaction temperature, acid to alcohol ratio, and catalyst loading is found to enhance the conversion of free fatty acid. In this study, the prediction of esterification reaction mechanism is conducted by a complex acid model. The influence of temperature on the kinetic constants was determined by fitting the results to the Arrhenius equation. The energy of activation for the forward reaction was found to be 67.9 kJ/mol. Vegetable-based esters are potential biodegradable base stocks for environmentally friendly lubricants. The basic lubrication parameters, such as acid value, viscosity, viscosity index, color, copper strip corrosion, foaming, and demulsifying properties, were tested and compared well with commercial standards.