Ammonia as a Carbon-Free Energy Carrier: NH3 Cracking to H2

In the energy transition from fossil fuels to renewables,hydrogenis a realistic alternative to achieving the decarbonization target.However, its chemical and physical properties make its storage andtransport expensive. To ensure the cost-effective H-2 usageas an energy vector, other chemicals are getting attention as H-2 carriers. Among them, ammonia is the most promising candidate.The value chain of NH3 as a H-2 carrier, consideringthe long-distance ship transport, includes NH3 synthesisand storage at the loading terminal, NH3 storage at theunloading terminal, and its cracking to release H-2. NH3 synthesis and cracking are the cost drivers of the valuechain. Also, the NH3 cracking at large scale is not a maturetechnology, and a significant effort has to be made in intensifyingthe process as much as possible. In this respect, this work reviewsthe available technologies for NH3 cracking, criticallyanalyzing them in view of the scale up to the industrial level.