Liquid Organic Hydrogen Carrier (LOHC) – Assessment based on chemical and economic properties. (8th March 2019)

• Record Type: Journal Article
• Authors: Niermann, Matthias; Beckendorff, Alexander; Kaltschmitt, Martin; Bonhoff, Klaus
• Is Part Of: International journal of hydrogen energy. Volume 44:Number 13(2019)
• Page Start: 6631
• Page End: 6654
• Publication Date: 2019-03-08
• Subjects: Liquid Organic Hydrogen Carrier -- LOHC -- Hydrogen economy -- Alternative fuels -- Hydrogen storage -- Assessment; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2019.01.199
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Hydrogen can be transported via long distances based on Liquid Organic Hydrogen Carriers (LOHC). Such a transport is realized based on a two-step cycle: (1) loading/storage of hydrogen (hydrogenation) into the LOHC molecule and (2) unloading/release of hydrogen (de-hydrogenation). During the storage period, hydrogen is covalently bound to the respective LOHC. Since the (optimal) LOHC is liquid at ambient conditions and shows similar properties as crude oil based liquids (e.g. diesel, gasoline), it can easily be handled, transported and stored; thus a stepwise implementation using the existing crude oil based infrastructure would be possible. Against this background this paper reviews the current knowledge in hydrogenation and de-hydrogenation of various LOHC. Therefore, a variety of LOHC is evaluated based on their properties and compared to each other. By applying different evaluation criteria representing the requirements of the three different application areas (energy-storage, energy-transport, mobility application), the LOHCs can be assigned to a field they suit best. The analysis shows that the most promising LOHC candidates to date are dibenzyltoluene for energy-transport and energy-storage as well as N -ethylcarbazole for mobility applications. In addition, a use of toluene in the transport sector is also conceivable. Methanol can potentially be applied in all three application fields due to its properties if a compromise between de-hydrogenation temperature and gas flow can be achieved based on further R&D-activities. For future implementation phenazine and formic acid show great potential, but also additional R&D especially regarding catalysis and solvents is necessary. Highlights: LOHC provide a sustainable solution to store and transport hydrogen. Assessment of eight selected LOHC for using in different application areas. Overview of important chemical and economic properties of the selected LOHC. Topics for further research on improving LOHC storage materials.