Fuel ammonia decomposition

For use in some types of fuel cells, the indirect storage of hydrogen in ammonia requires an efficient decomposition of ammonia with high conversion and low energy cost. The industrial catalyst for ammonia decomposition is... 

Choudhary T V, Sivadinarayana C, Goodman D W (2001), Catalytic ammonia decomposition COx-free hydrogen production for fuel cell applications, Catal. Lett., 72(3-4), 197-201. 

Yin S F, Xu B Q, Zhou X P, Au C T (2004), A mini-review on ammonia decomposition catalysts for on-site generation of hydrogen for fuel cell applications , AppZ. Catal. A, 111, 1-9. 

Ammonia may be stored at 8 bar as a liquid. Because proton exchange fuel cells are very sensitive to ammonia poisoning, hydrogen produced from ammonia decomposition is mostly applied in connection with alkaline fuel cells (see Section 2.3.2). 

Chellappa, A.S., C.M. Fischer, and W.J. Thomson. 2002. Ammonia decomposition kinetics over Ni-Pt/ AI2O3 for PEM fuel cell applications. Appl. Catal. A Gen. 227 231-240. 

Alagham, V, Palanki, S. West, K.N. Analysis of ammonia decomposition reactor to generate hydrogen for fuel cell applications. J Power Sources 195 (2010), pp. 829-833. 

C with partial decomposition. Synthesized from methanal and ammonia. Hexamine is used as starter fuel for camping stoves, as an... 

Due to the high hydrogen storage capacity of the ammonia molecule (17.7 wt% equal to an energy density of 4,318 Wh kg 1), its decomposition is intensely investigated for COx-free hydrogen production for mobile fuel cell applications [146]. However, compared with the well-established Haber Bosch process for ammonia synthesis, its decomposition is underdeveloped and requires substantial improvements before it can be considered as a practical contribution to the energy supply toolbox. 

When large spherical AP particles dg = 3 mm) are added, large flamelets are formed in the dark zone.Pl Close inspection of the AP particles at the burning surface reveals that a transparent bluish flame of low luminosity is formed above each AP particle. These are ammonia/perchloric acid flames, the products of which are oxidizer-rich, as are also observed for AP composite propellants at low pressures, as shown in Fig. 7.5. The bluish flame is generated a short distance from the AP particle and has a temperature of up to 1300 K. Surrounding the bluish flame, a yellowish luminous flame stream is formed. This yellowish flame is produced by in-terdiffusion of the gaseous decomposition products of the AP and the double-base matrix. Since the decomposition gas of the base matrix is fuel-rich and the temperature in the dark zone is about 1500 K, the interdiffusion of the products of the AP and the matrix shifts the relative amounts towards the stoichiometric ratio, resulting in increased reaction rate and flame temperature. The flame structure of an AP-CMDB propellant is illustrated in Fig. 8.1. 

The major fossil fuels are coal and petroleum. Marine organisms were typically deposited in mud and under water, where anaerobic decay occurred. The major decomposition products are hydrocarbons, carbon dioxide, water, and ammonium. These deposits form much of the basis for our petroleum resources. Many of these deposits are situated so that the evaporation of the more volatile products such as water and ammonia occurred, giving petroleum resources with little nitrogen- or oxygen-containing products. By comparison, coal is formed from plant material that has decayed to graphite carbon and methane. 

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