Modeling multiscale transport‐reaction in fixed bed reactors for CO 2 hydrogenation to aromatics

Abstract

Abstract CO 2 hydrogenation to aromatics via methanol is a promising alternative for the low‐carbon and sustainable production of aromatics. Herein, a two‐scale particle‐resolved computational fluid dynamics model is developed to reveal the complex transport‐reaction in the fixed‐bed reactor for this cascade reaction (i.e., CO 2 hydrogenation to methanol and methanol‐to‐aromatics) over tandem In 2 O 3 ‐HZSM‐5 catalysts. The results show that using the layered packing configuration with In 2 O 3 positioned upstream better matches the features of this reaction, exhibiting a 98% increase in the yield of aromatics compared with the random packing configuration. As it allows the methanol‐to‐aromatics reaction occurs over HZSM‐5 at a high methanol concentration. A In 2 O 3 to HZSM‐5 ratio of 1 can well coordinate the two cascade reaction steps. Besides, alleviating diffusion limitations via adopting Raschig ring pellet, small pellet size and large pore size can facilitate CO 2 consumption and aromatics generation, as well as suppress reverse water gas shift reaction.