MIHAELA GABRIELA DUMITRU, DELIA NICA BADEA, DRAGOS TUTUNEA DETERMINATION OF PHYSICOCHEMICAL PROPERTIES AND EMISSIONS FOR DIFFERENT BLENDS OF BIODIESEL FROM WATERMELON(CITRULLUS LANATUS L.) SEEDS AND DIESEL FUEL Across the world the fossil fuels are depleting and countries are forced to find an alternative source to reduce green house gases and replace petroleum fuels. Depending of the raw material sources, vegetable oils, animal fats or algae, biodiesel offers a solution for a clean-burning diesel fuel. Watermelon (Citrullus lanatus L.) seed were collected and the oil was extracted. The oil was transformed into fatty acid methyl esters through a transesterification process and blended in various proportions with diesel fuel. The physico-chemical properties of fuels were determined. Results obtained showed that the biodiesel has a density (0.870 g/cm3), kinematic viscosity 40°C (3.1 mm2/s), flash point (128°C), saponification index (150 mgKOH/g), iodine index (108 mgI2/100g), peroxide index (3.7 mEqO2/Kg) and oxidation stability (6 hours) in the range of UE specifications. The engine tests were conducted on a Deutz F4L912 diesel engine, 51 kW, 4-stroke, air cooled, direct injection diesel engine. From the test performed was observed that the CO and HC emissions were reduced due to high content of oxygen in biodiesel blends.