Biodiesel Production by Hydrodynamic Cavitation Through an Orifice Plate

Abstract

The traditional biodiesel production process consumes a large amount of energy by maintaining a reaction mixture of oil and alcohol for extended periods of up to 120 min at average temperatures of 60 °C. To reduce biodiesel production costs, alternatives have emerged that reduce reaction time and consequently the production costs. One of these alternatives is hydrodynamic cavitation, which through the contribution of sensitive heat, because of the phase change, allows to provide a large amount of energy to the fluids in reaction. Some elements that cause low pressures, which allows the presence of cavitation, are orifice plates. This paper presents the results obtained from the production of biodiesel by hydrodynamic cavitation caused by an orifice plate. These results are compared with those obtained by the traditional method of stirring and heating. For both processes soybean oil was used as raw material, a molar ratio of methanol oil 6:1 and 12:1, sodium hydroxide as catalyst at 0.5 % w/w and a reaction temperature of 60 °C. The biodiesel obtained was characterized by the standard EN14214 which establishes a minimum of 96.5% of FAME. The results show that this minimum value is exceeded at 17 min with the orifice plate, while with the traditional method the time was 120 min, demonstrating that hydrodynamic cavitation reduces the time and energy cost in biodiesel production.