Site items in: Hydrogen Purification

Ammonia cracking: when, how, and how much?
Paper

Cracking ammonia to produce hydrogen underpins many of the fuel-based uses of ammonia, and as such is a lynchpin technology in the case for ammonia energy. While in many ways ammonia cracking is a mature technology, systems which are designed specifically for these applications are less common. In this presentation, a general overview of the potential roles of ammonia cracking in facilitating the use of ammonia for energy applications will be outlined, including a survey of established and emerging cracking and purification technologies. A forthcoming project to produce an AEA Ammonia Cracking Technical Paper will be introduced.

Starfire Energy's ammonia cracking and cracked gas purification technology
Paper

Ammonia cracking is important for both combustion and fuel cell applications. Starfire Energy has verified that a blend of 70% ammonia + 30% cracked ammonia can burn well in a conventional natural gas burner with very low ammonia slip and acceptable NOx using a stoichiometric fuel-air mixture. A 10 MW turbine or internal combustion engine using such a blend will need about 1.44 tonnes of cracked ammonia per hour. Starfire Energy’s monolith-supported cracking catalyst may be ideally suited for this application. Fully cracked ammonia retains several thousand parts per million of ammonia due to thermodynamic limitations. Residual ammonia can damage…

Paper

Hydrogen is the primary fuel source for fuel cells. However, the low volume density and difficulty in storing and transporting hydrogen are major obstacles for its practical utilization. Among various hydrogen carries, ammonia is one of the most promising candidates because of its high hydrogen density and boiling point and ease in liquefaction and transportation. The reaction temperature of ammonia cracking into nitrogen and hydrogen is about 500˚C or higher. The hydrogen can be effectively separated by the membrane based on Pd alloy about 500˚C. Currently, the extraction of hydrogen from ammonia is carried out by two step process involving…

Ammonia-to-Hydrogen System for FCEV Refuelling
Paper

Ammonia can play a significant role in fuelling the world’s growing fuel cell electric vehicle (FCEV) fleet through technologies which allow the decomposition of NH3, and subsequent extraction and purification of H2. CSIRO has recently demonstrated a pilot-scale ammonia-to-hydrogen system, incorporating an ammonia decomposition stage with a subsequent membrane-based hydrogen purification stage, at a rate of several kilograms of H2 per day. Through partnerships with an industrial gas producer and two FCEV manufacturers, the resulting H2 has been compressed and dispensed into FCEVs. System design, materials, performance and strategies for scale-up and demonstration will be discussed.