Conceptual Design of Glycerol Hydrogenolysis Plant

In biodiesel production, an amount of glycerol equivalent to about 10% wt. of the total product is obtained. As a result of the increasing availability due to increase of biodiesel production, the market price of glycerol has dropped rapidly. Moreover, the disposal of glycerol by-product may become a problem in biodiesel production. Therefore, new uses for glycerol need to be found. Several publications [1-4] present multiple reaction schemes for glycerol hydrogenation to propanediols and ethylene glycol in the presence of metallic catalysts (fig. 1). These compounds are major commodity chemicals [5-7], with typical uses in unsaturated polyester resins, antifreeze, de-icing and heat transfer fluids, pharmaceuticals, foods, cosmetics, detergents, paints, etc. In spite of several research efforts, the study of this potentially important reaction was limited to laboratory scale. In this contribution, we report and evaluate the conceptual design of a glycerol hydrogenolysis plant. The necessar y process data was obtained by laboratory experiments. Several catalysts were experimentally tested and the most promising one, leading to 93% glycerol conversion and 72% selectivity towards 1,2-propanediol, was selected for further evaluation. The design of the glycerol hydrogenolysis plant was performed, using AspenPlus as a CAPE tool. Detailed stream report, equipment sizing and economic evaluation are presented.