Petrochemistry and Chemical Engineering

Biography

Biography: Peter Wasserscheid

Abstract

Hydrogen is often considered a very capable future energy vector. It can be produced from renewable wind or solar power via water electrolysis and has a wide range of potential applications in all important fields of energy supply. The gravimetric storage density of hydrogen is excellent. One kilogram H2 carries 33,3 kWh (LHV) of energy. However, being the chemical element with the lowest density, the volumetric storage density of hydrogen is only 3 Wh/liter at ambient pressure. In existing technical applications hydrogen is therefore either stored as gas under very high pressures (up to 700 bar, called “Compressed Gaseous Hydrogen” or CGH2) or in its liquid state at 253 °C (called “Liquid Hydrogen” or LH2). A very attractive way to store and release hydrogen is in form of “Liquid Organic Hydrogen Carriers” (LOHC) systems. Aromatic molecules, such as e.g. N-ethylcarbazole (NEC) [1] or dibenzyltoluenes [2] can be reversibly hydrogenated and dehydrogenated in order to store and transport hydrogen in form of diesel-like liquids. The presentation introduces shortly the LOHC concept for energy storage and future hydrogen logistics. Afterwards it concentrates on material and process aspects of LOHC hydrogenation and dehydrogenation catalysis covering the full range from studies on the molecular level (XPS-, IR-studies) to demonstrator units. Challenges and optimization potentials will be discussed; novel options (LOHC transfer hydrogenation, hydrogen purification through LOHC hydrogenation/dehydrogenation) will be presented.