Abstract
After synthesis, ammonia can be selectively absorbed by calcium chloride; nitrogen and hydrogen are not absorbed. The kinetics of release seem to be diffusion controlled. The kinetics of absorption are consistent with a first-order reaction after an initial period of a higher-order reaction, which may indicate a nucleation event. At 225 °C, both absorption and release show half-lives of around 10 min if the ammonia partial pressure is swung from 2 to 1 bar, which allows design of an absorber for the periodic separation of ammonia. When this absorber replaces the ammonia condenser in a conventional ammonia synthesis, the ammonia production at low pressure can have the same rate as the conventional process operating at higher pressure.
Original language | English |
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Pages (from-to) | 11827-11835 |
Number of pages | 9 |
Journal | ACS Sustainable Chemistry and Engineering |
Volume | 6 |
Issue number | 9 |
DOIs | |
State | Published - Sep 4 2018 |
Keywords
- Absorption
- Ammonia
- Kinetics
- Metal halide
- Pressure swing absorption