Chemical Hydrogen Storage

Research

M.Sc. Holger Jorschick
Copyright: C.Heßelmann

Examples are the modification of electrocatalysts with ionic liquids or hydrogen storage using Liquid Organic Hydrogen Carrier (LOHC) systems. The LOHC technologies allow large amounts of hydrogen with high volumetric energy density for infrastructure-compatible storage and transport of hydrogen. The research unit is led by Prof. Dr. Peter Wasserscheid. The research at HI ERN naturally extents existing research activities of his FAU group, for example towards direct LOHC fuel cell and electrolysis technologies.

Scheme: Storage and transport of hydrogen by reversible catalytic hydrogenation/dehydrogenation of dibenzyl-toluene/perhydro-dibenzyltoluene

The Scheme shows reversible hydrogen binding/release using these pure hydrocarbon LOHC compounds. During hydrogenation, H0-DBT is loaded with up to 6.2 wt% hydroge corresponding to an energy content of 2.05 kWh kg^-1. The energy-rich molecule H18-DBT is a high boiling liquid that can be stored in typical fuel tank for a long time without loss in energy. Molecular hydrogen can be released from H18-DBT by contact with a suitable catalyst at elevated temperature.

Full Cell Setup

Heated saturators for pressurized air and nitrogen or hydrogen.
Copyright: A.Kraus

M.Sc. Gabriel Sievi
Copyright: A. Kraus

For the investigation of fuel cells operated with organic fuels, a fuel cell setup is installed for testing various membrane electrode assemblies (MEAs). With this setup, it is possible to operate a single fuel cell with pressurized air (dry or humidified), hydrogen (dry or humidified) and different liquid, organic fuels. These fuels can be delivered liquid, gaseous or with a (humidified) carrier gas (nitrogen) to the cell. The quickConnect-setup also enables a fast switching between different MEAs, to vary between various membranes, catalyst loading or gas diffusion layers.

Kinetic modeling of the hydrogen release from Perhydro-Dibenzyltoluene

Estimation of model parameters by linear regression
Copyright: A. Bulgarin

M.Sc. Alexander Bulgarin
Copyright: A. Kraus

The overall optimization of the catalytic hydrogen release from the LOHC perhydro-dibenzyltoluene requires precise knowledge of the reaction system.
In order to describe the reaction progress mathematically, kinetic measurements are performed in a tubular reactor at lab-scale. For the estimation of kinetic parameters from experimental data, methods of linear and non-linear regression may be applied. The finally resulting parameterized model is a useful tool, e.g. in order to simulate dynamic operation of the dehydrogenation reactor or the effect of process parameters (e.g. temperature, pressure, residence time) on reactor performance.

Collaborations

• Dr. Peter Pfeiffer, Prof. Roland Dittmeyer (KIT, Germany)
• Prof. Regina Palkovits, Prof. Walter Leitner (RWTH Aachen)

Groups