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The increasing population and economic growth of a number of developing countries, conjugated with dwindling petroleum reserves, has amplified the world demand for alternative energies. Moreover, to a large extent climate changes have been linked to the burning of fossil fuels which leads to the emission of large quantities of greenhouse gases. In this scenario it is important to develop new renewable energy sources that can meet the global energy demands without harming the environment. Biodiesel and bioethanol are among the most promising new alternative fuel sources generating a new industry segment called biorefinery. It is possible that, in a no so distant future, biorefineries will produce a large variety of bioproducts that will be applied in many sectors of the chemical industry.ഀ In the case of the oleochemical industry, based in the vegetable oil and biodiesel production some compounds such as fatty acids, triacylglycerols, fatty alcohols and nutraceutical compounds can be present in practically all process stages. These substances, in some stages considered as byproducts, can be separated and sold as added value products used in the formulation of cosmetic, pharmaceutical or food products, for example. ഀ In turn, fatty acid ethyl or methyl esters, components of biodiesel, should attend several specifications that stipulate the limit values for the low-temperature properties of the fuel, such as the Cloud Point, CP (EN 23015, ASTM D-2500), the Pour Point, PP (ASTM D-97, ASTM D-5949), the Cold Filter Plugging Point, CFPP (EN 116, IP-309, ASTM D-6371) and the Low Temperature Filterability Test, LTFT (ASTM D-4539)5. The Cloud Point (CP), for example, is the temperature at which a hazy appearance develops on a fuel upon cooling due to the crystallization of the heavier fatty acid esters. With further temperature decrease the crystal particles grow and agglomerate, reducing the capacity of the liquid to flow through porous media plugging the fuel filters. The importance of the knowledge of the solid-liquid equilibrium of fatty esters remains in the purification of biofuel too as well as in the formulation of the biofuel whereas a biodiesel produced from oils or fats with considerable amounts of saturated triglicerides will display high cloud points, for example. ഀ The aim of this study was determine and analyze a set of phase diagrams of binary fatty mixtures due to the importance of such components in the vegetable oil and biodiesel production, its added value when pure and the possibility of products formulation. It was determined by differential scanning calorimetry technique (DSC) 85 phase diagrams: 13 mixtures formed by two saturated fatty acids, 12 mixtures of saturated fatty alcohols, 27 mixtures of ethyl esters, 3 mixtures of methyl esters, 16 mixtures of one saturated fatty alcohol plus one saturated fatty acid and more 14 binary mixtures of saturated or unsaturated fatty acids with triacylglycerols. The solid phase of some phase diagrams were studied using X-ray diffraction, FT-Raman spectroscopy and optical microscopy.ഀ