Ammonia cracking

Ammonia can be decomposed into nitrogen and hydrogen at a cracking unit. Ammonia cracking at small scale (1-2 ton per day [tpd]) and high temperature (600-900 °C) using inexpensive materials, such as iron, is already commercially available. However, the energy consumption of high-temperature ammonia cracking is around 30% of the energy content of the ammonia and rarely includes hydrogen purification. Ammonia cracking at lower temperatures (~450 °C) would decrease energy consumption, but currently involves the use of precious-metal catalysts, such as ruthenium. Low temperature ammonia cracking without the use, or with a limited use, of precious metals as catalysts is still at low maturity levels. In addition, the technology for separation and purification of hydrogen after ammonia cracking also needs to become less costly and more efficient, e.g. complying with the composition requirements set out for fuel cells (H2>99.97%, NH3<0.1 ppmv, N2<1000 ppmv). Innovation around ammonia cracking needs to address challenges on efficiencies, costs, purity and scale.