COX-free LOHC dehydrogenation in a heatpipe reformer highly integrated with a hydrogen burner

We introduce a thermally self-sustained reactor concept highly integrated with a heat source to produce hydrogen (H₂) stored in methylcyclohexane (MCH), the liquid organic hydrogen carrier (LOHC). This work has a great potential to promote the use of LOHC for CO_x-free H₂ production for on-board or mobile applications. To this end, the heat-pipe dehydrogenator, an H₂ burner, and a thermal management module are developed. We initially perform a numerical simulation to optimize reactor wall materials and configuration and experimentally test them to reveal the feasibility of such a highly integrated system to maintain uniform reaction temperature at 320 – 360 °C, optimal for MCH dehydrogenation. In the proposed design, the heat required for the reaction is provided by the combustion of a part of released H₂, and transferred via a gas–liquid organic phase-change material (PCM). In the as-developed H₂ generator with 50.4 NL_H2/h (equivalent to 138.5 W_LHV-basis), we achieve a high reforming efficiency of 80% with an MCH conversion of > 99.7%. We expect the as-developed system to be a stepping stone to expanding the use of LOHC in versatile applications requiring carbon-free H₂ storage and production after further engineering efforts to enhance heat recovery and thermal circulation.