Biodiesel production in a rotating packed bed using K/γ-Al2O3 solid catalyst

The methanolysis of soybean oil with a K/gamma-Al2O3 catalyst using a rotating packed bed (RPB) for the production of fatty acid methyl esters (biodiesel) is presented. The RPB, which provides high centrifugal force and has an adjustable rotational speed, was employed as a novel heterogeneously catalyzed transesterification reactor. The methanol-to-oil molar ratio, the catalyst dosage, the rotational speed of the packed-bed rotator, and the reaction temperature were investigated for their effects on the yield of fatty acid methyl esters (Y-FAME) in the RPB. Furthermore, the modified first-order reaction kinetics was employed to study the transesterification reaction rate of the K/gamma-Al2O3 catalyzed RPB system. In addition, the transesterification performance and durability of the K/gamma-Al2O3 catalyst with respect to Y-FAME using the RPB system were evaluated, allowing for further comparison with other heterogeneously catalyzed transesterification reactors. Based on the results, the RPB system is considered as a practical, heterogeneously catalyzed transesterification reactor due to its excellent micromixing characteristics. (C) 2011 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.