Effect of carbon dioxide impurities on the Haber–Bosch process

The Haber–Bosch process is a highly exothermic reaction that is used to produce ammonia from nitrogen and hydrogen. The nitrogen is typically obtained from the air using a membrane separation process, which results in a product that is 95-99.5% pure. However, there are still small amounts of impurities present, such as oxygen and $\ce{CO2}$.


Oxygen can be easily reduced by incoming hydrogen, so it is not a major concern. However, $\ce{CO2}$ is an inert gas that can inhibit the reaction between nitrogen and hydrogen. The effect of $\ce{CO2}$ on the Haber–Bosch process is not well-understood, but it is thought that even small amounts of $\ce{CO2}$ can have a significant impact on the yield of ammonia.


I am interested in learning more about the effect of $\ce{CO2}$ impurities on the Haber–Bosch process. In particular, I would like to know:


* What is the mechanism by which $\ce{CO2}$ inhibits the reaction between nitrogen and hydrogen?
* How does the concentration of $\ce{CO2}$ affect the yield of ammonia?
* Are there any methods to remove $\ce{CO2}$ from the nitrogen feedstream before the Haber–Bosch process?


I believe that this question is of interest to the chemistry community, and I hope that you will consider answering it.


Thank you for your time.


