Advanced biodiesel production technologies: novel developments

摘要: Biodiesel, i.e. a mixture of monoalkyl esters long chain fatty acids derived from renewable biological sources such as vegetable oils has in recent years emerged an alternative fuel for transportation sector. The conventional method producing biodiesel is through homogeneous catalytic transesterification; however, increased production costs associated with downstream purification steps have led to the development more cost-effective and environmental friendly technologies. These advanced technologies involve heterogeneous or enzymatic catalysts produce biodiesel, well no supercritical conditions. Heterogeneous systems can ease separation reaction along possibility catalyst recovery, potentially leading lower costs; give same advantages, but transesterification be carried out milder conditions wider range feedstocks. Biodiesel synthesis composes another methods due higher rates, shorter times, simpler steps. Nevertheless, mass transfer limitations caused by diffusion problems between phases represent hindrance future establishment these technologies, calling novel intensify process. process intensification include ultrasound irradiation, microwave heating, use co-solvents, membrane reactors. main focus this review discuss advances regards devoting special attention catalysts, diversified feedstocks, besides analysis operational parameters processes.