Pour point prediction of biodiesel-ethanol blends by near-infrared spectroscopy

Pour Point measurement is essential to assess biodiesel use in cold weather. In this work, biodiesel samples were obtained from 4 different types of cooking oil (sunflower oil, sunflower and soya oil, sunflower and corn oil, and corn oil). Biodiesel mixtures with ethanol were prepared by weight (% w/w). The pour point of the mixtures was measured according to the ASTM D97-08 procedure, which needs a cooling bath, able to attain very low temperatures (till −16 °C in the present work), and it is based on visual inspection of the mixture flowing ability. However, this procedure is tedious and time-consuming.