Spanish researchers propose new LOHC-based system for on-demand hydrogen production, storage and transport
A group of researchers in Spain—from the Universitat Jaume I de Castelló, the University of Zaragoza and the Institute of Chemical Technology of the Universitat Politècnica de València-CSIC—coordinated by Professor José Antonio Mata of the UJI, have developed and patented a new procedure for the efficient on-demand production, storage and safe transport of hydrogen based on the use of liquid hydrogen organic carriers (LOHC).
The research team has studied different hydrogen-bearing organic liquids to arrive at the new hydrogen storage system based on a chemical coupling reaction between a hydrosilane and an alcohol catalyzed by a ruthenium compound supported in graphene. Their paper is published in Chemistry: a European Journal.
|Implementation of silane/alcohol as a liquid organic hydrogen car- rier catalyzed by ruthenium. Ventura-Espinosa et al. Click to enlarge.|
Hydrogen storage in the form of liquid organic hydrogen carriers (LOHC) is very promising.In the present work, we analyse the catalytic dehydrogenative coupling of hydrosilanes with alcohols as a potential system for hydrogen storage.
A potential LOHC requires a fast dehydrogenation reaction to control the production of molecular hydrogen on-demand. The dehydrogenation coupling of hydrosilanes and alcohols is a catalytically controlled process. As is shown herein, the ruthenium complex [Ru(p-cym)(Cl)2(NHC)] is a very efficient catalyst, controls reaction kinetics, and produces hydrogen at high rates.
A major drawback found in most LOHCs is the elevated temperatures required in the dehydrogenation process. The coupling reaction of hydrosilanes and alcohols is carried out at low temperatures and proceeds even at 08C. The different types of hydrosilanes and alcohols available make the system a versatile LOHC.—Ventura-Espinosa et al.
The new process is chemically versatile as there are many combinations of hydrosilanes and alcohols that can be employed. Further, the process can be performed very fast and no elevated temperatures are required, as the ruthenium catalysts are highly efficient for this reaction. Third, the process is reversible because the product formed in the coupling between a hydrosilane and alcohol is a silyl ether that can be further transformed into the original product by a reductant.
The system can be easily adapted to non-static energy generation and use systems, such as automobiles; the use of silane-alcohol as LOHC allows working at low temperatures in obtaining the gas and the technology circumvents the safety problems of hydrogen storage.
Ventura-Espinosa, D., Carretero-Cerdán, A., Baya, M., García, H. and Mata, J. A. (2017) “Catalytic Dehydrogenative Coupling of Hydrosilanes with Alcohols for the Production of Hydrogen On-demand: Application of a Silane/Alcohol Pair as a Liquid Organic Hydrogen Carrier.” Chem. Eur. J. doi: 10.1002/chem.201700243