TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The extraction phase is performed by continuous extraction. When the solvent substance is an apolar organic solvent, then the extraction phase is performed for 1-10 hours (preferably 2-8 hours) at boiling temperature of the solvent, or at a temperature between room temperature and the boiling temperature of the solvent. When the solvent substance is carbon dioxide (CO2) in supercritical phase, then the extraction phase is performed with an extraction ratio of 1 kg mass/20-60 l supercritical CO2 and a flux rate of 5-20 m3/hour (preferably an extraction ratio of 1 kg/35 l supercritical CO2 and a flux rate of 15 m3/hour) for 2-8 (preferably 3-5) hours at a pressure of 200-900 (preferably 650) bars and a temperature of 40-90 degrees C (preferably 90 degrees C). The procedure includes a separation phase from the biofuel obtained of a liquid phase and successive micro- or ultrafiltration of the liquid phase, with the recovery of a second biofuel solid fraction and low energetic content. The process further involves carrying out a mixing phase of second biofuel solid fraction with the solid residue from the extraction phase to give a biofuel with medium energetic content (i.e. energetic content of higher than 3.500 kcal/kg). Preferred Components: The organic fraction has a solid material content of below 25 wt.%. The solvent substance is an apolar organic solvent (preferably pentane, heptane, octane, gasoline solvent, trichloroethylene, carbon sulfur or paraffinic solvents or their mixtures); or is carbon dioxide (CO2) in supercritical phase. The organic fraction is previously deprived of inert material such as metals, or plastics. EXAMPLE - An extraction of organic fraction (2-3 kg) of 2 different municipal wastes (Total solids (TS) of 28 plus minus 1.4%, volatile solids (VS) of 94 plus minus 1.7%, and pH of 4.6 plus minus 0.08) was proceeded by using supercritical CO2 at 650 bar and 90 degrees C (where the CO2 was heated at 90 degrees C) for 5 hours, adopting an extraction ratio of 1 kg of organic fraction/35 l CO2 and a flux rate of 15 m3/hour. After work-up, a biofuel was obtained. The biofuel obtained had an yield of 7 wt./wt.%, pH of 4.03, energetic content of 31 plus minus 2540 kJ/kg, carbon content of 67 plus minus 2, hydrogen content of 10.25 plus minus 1.2, nitrogen content (%TS) of 0.11-0.12, sulfur content of 0, and an oxygen content of 22.44.