Zur Kinetik der technischen Ammoniaksynthese

On the Application of the Temkin Equation in the Evaluation of Catalysts for the Ammonia Synthesis

“…The fact that such good agreement between experimental and calculated data was never obtained before is to be ascribed to the experimental data previously employed in checking this equation. In fact, elaborating with our calculation program some of the experimental results by Nielsen (1968) (whose kinetic data were employed by many authors (Bokhoven et al, 1955; Bokhoven and Van Raayen, 1954;Buzzi Ferraris and Donati, 1970;Buzzi Ferraris et al 1974; Dyson and Simon, 1968;Haijs and Poska, 1964;Huber, 1962) for their investigations), an average percent error of 7.47% (Table V) is found, which is considerably higher than those recorded in our experiments.…”

“…a Calculated with not rounded values and Kummer, 1943;Huber, 1962;Livshits and Sidorov, 1952; . Love andEmmett, 1941;Mills and Bennett, 1959;Nielsen, 1968;Ozaki et al, 1960;Sidorov and Livshits, 1947; …”

Simulation of Ammonia Synthesis Reactors

“…where rNH3 = reaction rate, kg-mol of NH3/(h m3 of catalyst), K2 = velocity constant of the reverse reaction, kg-mol/(h m3), /N¡¡, /Ha, /nh3 = fugacities of nitrogen, hydrogen, and ammonia, respectively, ka = equilibrium constant of the reaction: 1.5H2 + 0.5N2 -NH3, and a = constant. According to some workers a = 0.5 for all iron catalysts (Morozov et al, 1965;Temkin and Pyzhev, 1940;Temkin et al, 1963) whereas others obtained values ranging from 0.4 to 0.8 (Anderson, 1960; Bokhoven et Ferraris and Donati, 1970;Cappelli and Collina, 1972;Dyson and Simon, 1968;Emmett and Hummer, 1943;Guacci et al, 1977;Huber, 1962;Livshits and Sidorov, 1952;Love and Emmett, 1941;Mills and Bennett, 1959;Nielson, 1968;Ozaki et al, 1960;Sidorov and Livshits, 1947;Sholten, 1959).…”