To achieve a truly renewable energy market, the intermittent power generation of sources such as solar and wind must be overcome. Renewable ammonia can be synthesized using these sources to be used as a long-term energy storage medium. For this reason, the use of ammonia as a synthetic fuel has garnered significant attention in recent years. Aqueous AAN (ammonia/ammonium nitrate) is a carbon-free ammonia based monofuel suitable for energy storage applications. This fuel is safe to store and transport, and its combustion products consist mainly of water and nitrogen. Effective use of this fuel requires an in-depth understanding of the reaction pathways dominating its ignition.
In this work, the accumulated results from experiments conducted to test the effects of water content, equivalence ratio, and diluent pressure on AAN ignition will be reviewed. The use of simulations to reproduce these results will be evaluated, and the data generated by rate-of-production and sensitivity analyses will be reviewed. Finally, the reaction pathways involved in AAN ignition and their relation to its water content, equivalence ratio and diluent pressure will be presented, and the implications of the rate-determining steps for AAN ignition will be discussed.