Ammonia is made from hydrogen and nitrogen over a catalyst operating at high temperature and pressure. More ammonia can be produced by changing how the ammonia synthesized is separated, i.e., by replacing the current condensation of ammonia with absorption in salts like magnesium chloride. This paper uses the concept of resistances in series in conjunction with experiments of absorption and a well-established theory of reaction to identify conditions where the rate of ammonia synthesis can be increased. For example, in one case, if a condenser in a conventional process is simply replaced with an absorber, the increase in production rate per mass of catalyst is capped at 10%. However, if the recycle rate is simultaneously increased, the increase in production rate per gram of catalyst can exceed 1000%.
Bibliographical noteFunding Information:
This work was funded largely by the Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award DE-AR0000804. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Other funding came from the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR), and from the MnDRIVE initiative of the University of Minnesota.
© 2019 American Chemical Society.
- Production rate