The need for safe and efficient hydrogen storage and release is driving research into Liquid Organic Hydrogen Carrier (LOHC) systems,where hydrogen is chemically bound to a carrier molecule and later released on demand. Among these, the reversible hydrogenation and dehydrogenation of dibenzyl toluene (DBT) to its hydrogenated counterpart (perhydro dibenzyl toluene, DBTH) is attracting significant attention.
This work focuses on the development and simulation of a dynamic reactor model for the hydrogenation/dehydrogenation process of DBT. The three-phase reactor model is built upon a series of experimental tests at various operating temperature, where the concentration of each species in the liquid phase has been measured to detect the time-variation of the species involved. This information has been used to develop a dynamic model that allowed to generate a digital twin of the reaction environment.
The dynamic model extends the general steady-state formulation by integrating the mass balance equations over time, using a process simulator (Aspen Plus), allowing the simulation of transient phenomena such as start-up, feed rate variations, and reactor response to external perturbations. along with the implementation of a simple control system. Validation of the reactor model was achieved by comparing simulation outputs with available experimental data. The dynamic predictions for the molar compositions were found to be in good agreement with experimental measurements. A sensitivity analysis was also performed to identify the impact of key parameters, such as catalyst loading and reaction temperature, optimizing reactor design by pinpointing the factors that most strongly influence conversion efficiency and dynamic response. The model developed demonstrates the feasibility of using computational methods to simulate the complex hydrogenation–dehydrogenation reactions in LOHC systems and has been conducted within the NACHIP project, which aims to provide a robust computational framework for designing and optimizing modular reactors for LOHC for mobility and stationary applications
