Of nitrogen on iron

In the case of nitrogen on iron, the experimental desorption activation energies are also shown in Fig. XVIII-13 the desorption rate was given by the empirical expression... 

Scholten, J. J. F., Chemosorption of Nitrogen on Iron Catalists in Connection with Ammonia Synthesis. Croniger, Amsterdam, 1959. 

Fastrup, B. (1994) Temperature programmed adsorption and desorption of nitrogen on iron ammonia synthesis catalysts, and consequences for the microkinetic analysis of NH3 synthesis. Top. Catal., 1, 273. 

Figure 38 gives the heats of chemisorption of nitrogen on iron films, recently published by Bagg and Tompkins (363), and we may compare the decrease of this curve with the increase shown by the curve of Fig. 36. 

Temkin assumed a heterogeneous surface and set up equations for the adsorption equilibrium of nitrogen on iron, for the rate of adsorption, and for the rate of de-... 

Surface Science of Ammonia Synthesis Structure Sensitivity of Ammonia Synthesis Kinetics of Dissociative Nitrogen Adsorption Effects of Aluminum Oxide in Restructuring Iron Single-Crystal Surfaces for Ammonia Synthesis Characterization of the Restructured Surfaces Effect of Potassium on the Dissociative Chemisorption of Nitrogen on Iron Single-Crystal Surfaces in UHV... 

J.J. Scholten, P. Zwietering, J.A. Konvalinka, and J.H. de Boer. Chemisorption of Nitrogen on Iron Catalysts in Connection with Ammonia Synthesis. Part 1. The Kinetics of the Adsorption and Desorption of Nitrogen. Trans. Faradav Soc. 55 2166 (1959). 

Hlfcci of Potassium on the Di.ssociaiivc ChcmiM)rption of Nitrogen on Iron Single-Crystal Surfaces in UHV. 475... 

Significantly, he turned his attention to questions on physical adsorption of gases on surfaces. He published the results of his work on relative adsorption of H2 and D2 and, with Otto Beeck and E. A. Smith, on the activated adsorption of nitrogen on iron and the significance of this to NH synthesis. 

Type 2 Adsorption of nitrogen on iron catalysts at -195 C (many solids fall into this type). 

It can be seen from the above-mentioned discussion that the Temkin s theory of catalytic reaction kinetics on heterogeneous surfaces is confirmed not only by overall reaction kinetic data of ammonia synthesis, isotherms and adsorptive rates of nitrogen on iron catalysts, more importantly, perhaps, but also some very useful generalization results derived from this theory. For instance, Temkin s equation is obtained based on two steps or simplified two steps mechanism. So, it can apply to any kind of catalytic reactions. The problem is Are some simplifications required by reasonable formation of two step mechanism, and can the assumption of rate determining step be made for non-uniform surface The answer of Temkin s theory is positive, and especially Temkin s theory of catalytic reaction kinetics on non-uniform plays an important role in solving the selection and improvement of catalysts. 

In this section a large amount of work which has been performed outside the Lawrence Berkeley Laboratory (except for Section 4.4.4) is summarized. The structure and bonding strength of potassium will be discussed along with the effect of potassium on the dissociative chemisorption of nitrogen on iron single-crystal surfaces. 

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