(442e) Biodiesel Production Using An Intensified Spinning Disc Reactor

Biodiesel, as an alternative fuel, has attracted more attention and been more widely accepted because it is made from renewable feedstocks. Usually biodiesel is synthesized from transesterification of vegetable oils or animal grease with alcohols in a stirred tank reactor (STR) in the presence of acid or base. Transesterification reaction is reversible and its reaction rate is limited by mass transfer between immiscible two phases. Hence, biodiesel production requires long residence time, high molar ratio of alcohol to oils and catalyst concentration, leading to high operating cost and energy consumption, and low production efficiency. In this paper, a novel intensified spinning disc reactor (SDR) with a stator, which has been developed to improve the mixing and mass treansfer between methanol and oil, thus increasing the product efficiency of biodiesel production via alkali-catalyzed transesterification is described. The modified SDR includes a stationary disc, which is coaxially spaced adjacent to a rotating parallel disc separated by only a fraction of a millimeter. The configuration may lead to intense, forced molecular inter-diffusion of liquid-liquid two phases caused by high shear rate. The performance of the new SDR has been investigated by examining the effects of gap sizes between the discs, rotational speed, flowrate of oil phase and designs of the rotating disc. Additionally, reaction conditions have been optimized to determine the values of molar ratio of methanol to oil, reaction temperature and catalyst concentration which result in the highest biodiesel conversion. Finally, the performance of the intensified SDR has been compared with that of a STR.