Modeling of the Continuous Dehydrogenation of Perhydro‐Dibenzyltoluene in a Cuboid Reactor

Abstract

The use of the dibenzyltoluene/perhydro‐dibenzyltoluene (H18–DBT) system as a liquid organic hydrogen carrier (LOHC) enables the safe and loss‐free storage of hydrogen. The release of hydrogen from the LOHC is a catalytic reaction and requires ≈27% of the lower heating value of the released hydrogen in the form of heat neglecting heat losses. The high heat requirement makes it necessary to design chemical conversion units that both provide good heat input and accommodate the high gas release. Up to 1200 L of hydrogen is released from 1 L of LOHC under reaction conditions. In this work, a cuboid reactor for the release of hydrogen from H18–DBT is demonstrated. In the experiments, it is shown that evaporation has a significant effect on the reaction rate and thus the amount of hydrogen releases. Therefore, a kinetic model capable of accounting for the release rate and evaporation in the reactor is developed. The model is successfully validated and shows deviations of less than 15% between measured and modeled hydrogen flow in the entire range considered. Since the model considers this important interaction between evaporation and hydrogen release for the first time, it is suitable for optimizing the reactor used.