Catalytic Ammonia Synthesis

In the ammonia synthesis process like most other processes the main processing unit and one that attracts most attention from a control point of view is the rector. In ammonia production plant there exists two reactors, the mathanation and the synthesis. The methanation reactor is of much less importance as little amount of reaction takes place in it, while the synthesis reactor is of outmost importance. In this paper initially a four-bed ammonia synthesis catalytic reactor is simulated in a dynamic environment. The simulation is then used to analyze the effect of sudden change on feed pressure and variation of feed distribution on different beds on process parameters such as temperature, pressure, flow rate and concentration through the process. 

Like the ammonia synthesis, catalytic oxidation of carbon monoxide is at the core of a major technological process, namely the removal of toxic substances from automobile exhaust. In a catalytic converter, the exhaust fumes interact with the surface of fine-grained particles of metals from the platinum group. While the carbon monoxide (CO) molecules are adsorbed by the surface of the catalyst, the oxygen molecules (O2) contained in the fumes are dissociatively chemisorbed. 

ErtI G 1991 Catalytic Ammonia Synthesis Fundamentals and Practice, Fundamentals and Applied Catalysis ed J R Jennings (New York Plenum)... 

The hydrogen can be used for organic hydrogenation, catalytic reductions, and ammonia synthesis. It can also be burned with chlorine to produce high quaHty HCl and used to provide a reducing atmosphere in some appHcations. In many cases, however, it is used as a fuel. 

Throughout the book we use the terms catalysis, catalyst and catalytic reaction referring to processes which do not involve any net charge transfer, such as e.g. the oxidation of CO on Pt or the ammonia synthesis on Fe ... 

The development of ammonia synthesis represents a landmark in chemical engineering, as it was the start of large-scale, continuous high-pressure operation in flow reactors, and in catalysis, because the numerous tests of Mittasch provided a systematic overview of the catalytic activity of many substances. 

The ammonia synthesis process consists of a series of catalytic reactions that aim to make a mixture of N2 and H2 without components that would deactivate the catalyst. Ammonia is formed only in the last reactor. 

The studies of ammonia synthesis over Fe and Re and the hydrodesulfurization of thiophene over Mo, described above, illustrate the importance and success of our approach of studying catalysis over single crystal samples at high pressures. The use of surfaces having a variety of orientations allows the study of reactions that are surface structure sensitive 6Uid provides insight into the nature of the catalytic site. Here we have shown that the ammonia synthesis... 

---