Other Manufacturing Processes for Hydrogen

However, multistep thermochemical cyclic processes, of which a number are thermodynamically possible, can be carried out at lower temperatures. In such processes the splitting of water is assisted by an auxiliary agent which is fed into the cycle and the reaction products, in part via intermediates, are thermally split. One example from the so-called Iron-Chlorine-Family is the following three step process  

Material and corrosion questions as well as the realization of the necessary high temperatures (possibly nuclear process heat or solar energy) have hindered their application. 

Photochemical, photoelectric and thermochemical processes currently have no commercial significance. 

For particular purposes, hydrogen is produced by catalytic decomposition of ammonia (by contact with nickel at 900°C for hydrogenation or metallurgical purposes) or methanol in cracking plants. 

H2 produced as a byproduct in refineries and photochemical companies particularly from  

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