TECHNOECONOMIC ANALYSIS OF AREA II HYDROGEN PRODUCTION - PART II Hydrogen from Ammonia and Ammonia-Borane Complex for Fuel Cell Applications

The aim of this analysis is to assess the issues of cost, safety, performance, and environmental impact associated with the production of hydrogen by so called "Area II" technologies, not presently funded by the U.S. DOE Hydrogen Program. The hydrogen (H2) rich feedstocks considered are: water, hydrogen sulfide (H2S) rich sub-quality natural gas (SQNG), and ammonia (NH3). Three technology areas to be evaluated are: 1) Thermochemical H2S reformation of methane with and without solar interface, 2) Thermochemical water-splitting cycles suitable for solar power interface, 3) Ammonia and ammonia adducts as hydrogen energy storers for fuel cell applications. This project is a multi-year effort with following objectives: • Analysis of the feasibility of the technology areas 1-3 from technical, economical and environmental viewpoints. • Evaluation of the cost of hydrogen production by technology areas 1 & 2. • Feasibility of the technology area 3 as a means of supplying H2 to fuel cell power plants. This paper provides the second in a series of analysis focusing on the prospects of ammonia and ammonia-borane compounds for use as hydrogen carriers for fuel cell applications. Due to extreme toxicity of ammonia, it is difficult to envision its widespread use as the future transportation fuel. This is despite the fact that ammonia is a low cost, readily available, environmentally clean and very high-density hydrogen energy storer. One approach to mitigate this problem is to complex ammonia with a suitable hydride so that the resulting material is neither toxic nor cryogenic. A class of compounds known as amine-boranes and their certain derivatives meet this requirement. The simplest known stable compound in this group is ammonia-borane, H3BNH3 (or borazane). Borazane is a white crystalline solid that upon heating reacts to release hydrogen in a sequence of reactions that occur at distinct temperature ranges. Ammonia-borane contains about 20 wt% hydrogen and is stable in water and ambient air. 1 Proceedings of the 2002 U.S. DOE Hydrogen Program Review