ABSTRACT
Hydrogen (H2) possesses a number of chemical and physical properties that have allowed it to be used widely in the synthesis and processing of materials in research laboratories as well as in industrial manufacturing. These uses are in addition to the emerging use of hydrogen in power generation technology, including transportation, as discussed in Chapter 2. Except for situations such as in the petrochemical industry, in which hydrogen is utilized more or less immediately after its production from a hydrocarbon feedstock, most applications require that hydrogen be stored after its production by some method prior to its eventual endpoint usage. Many factors influence the physical state (i.e., gas, liquid, solid, or contained in a chemical substance) in which hydrogen will be stored and how it will be supplied for a specific application. In those situations where hydrogen has been a well-established commodity, the physi-
cal state is well understood, and storage systems have been developed over the years. For example, hydrogen is often used as a reactant in laboratory research or in manufacturing. In these applications, compressed hydrogen gas is deployed in appropriate size cylinders at pressures up to about 200-300 bar. In addition, when hydrogen is used in a unique and critical capability (e.g., as a rocket propellant for launching spacecraft), then
CONTENTS
Introduction ...................................................................................................................................65 Compressed Gas Hydrogen Storage .......................................................................................... 67 Cryogenic Hydrogen Storage Systems ...................................................................................... 69 On-Board Reversible Hydrogen Storage Materials and Systems .......................................... 74
Interstitial Metal Hydrides...................................................................................................... 74 Complex Metal Hydrides ........................................................................................................77 Adsorption Materials ............................................................................................................... 78
Off-Board Reversible Hydrogen Storage Materials and Systems ..........................................80 Liquid Organic Hydrogen Carriers ....................................................................................... 81 Hydrolysis Reactions ............................................................................................................... 81 Metal Hydrides and Ammonia Borane .................................................................................84
Concluding Remarks ....................................................................................................................84 Acknowledgments ........................................................................................................................85 References .......................................................................................................................................85
cryogenic liquid hydrogen (LH2) is used and stored in cryogenic containment vessels as part of the launch vehicle. On the other hand, whenever hydrogen is to be used in a role that would either replace existing technologies or serve a novel function, the current storage approaches generally must be heavily adapted, or new ones developed, to meet the different operating parameters and constraints. Chapter 1 describes the increasing concerns over the energetic, political, and environ-
