Progress in ammonia synthesis at normal pressure and temperature

1 Progress in ammonia synthesis at normal pressure and temperature 

Although the standard equilibrium constant for ammonia synthesis reaction at 298 K is 6.8 x 10 , the reaction rate is not detectable. To increase the reaction rate and activate catalyst at optimal temperature, the industrial synthesis ammonia is carried out at 400°C-500°C. Because of the thermodynamic limitation, the standard equilibrium constant is 1 x 10 at this temperature which leads to low conversion. In order to enhance conversion, it is common to introduce high pressure and increase concentration of N2 to move the equilibrium to right. However, the conversion of ammonia s3mthesis in one attempt is 10%-15% only. 

Therefore, it is a new challenge to speculate ammonia synthesis at normal temperature and pressure. Fixed nitrogen is critical for life and development of human being. Therefore, scientists are engaged in pursuing the target of ammonia synthesis at normal temperature and pressure and have made many achievements. 

It is a key problem of how to activate nitrogen molecules and how to supply energy in order to fix and come down from dissociative dinitrogen in air and to realize ammonia synthesis at normal temperature and pressm-e. 

The electron arrangement of nitrogen molecule is (ls) (ls ) (2s) (2s ) (2p) (2p), and electron structure is where the bond- 

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