Process development for the synthesis of saturated branched fatty derivatives: Combination of homogeneous and heterogeneous catalysis in miniplant scale

摘要

Saturated branched fatty derivatives find application in lubricant and cosmetic industry due to the decisive advantages in temperature and viscosity behavior compared to their linear homologs. Thus, finding new synthesis routes, particularly based on renewable resources, is of great industrial interest. This work covers a new synthesis route for production of such saturated branched derivatives based on linoleic methyl ester. The developed process combines homogeneously rhodium catalyzed co-oligomerization of linoleic methyl ester with ethylene and heterogeneously catalyzed hydrogenation of the co-oligomers in miniplant scale. The paper focuses on the hydrogenation in trickle bed reactor and optimization of operation conditions as well as optimization of packings and liquid distribution. Saturated branched derivatives with very low iodine values have been produced in miniplant scale using a diluted catalyst packing consisting of large Pd/C catalyst pellets and small SiC particles. Different SiC fractions have been tested to investigate the effect on liquid distribution. Additionally long term stability of the heterogeneous Pd/C catalyst has been successfully tested for more than 100 h. Simultaneous adsorption of the used homogenous rhodium catalyst on the fixed bed was analyzed by XPS. Additionally this paper discusses the general transferability of the process combination consisting of homogeneous and heterogeneous reaction steps to other synthesis route and product groups. (C) 2015 Elsevier Ltd. All rights reserved.