1164.    GAUKHMAN, S. S., AND ROITER, V. A.  [Role of Sorption of Nitrogen in the Mechanism of Ammonia Synthesis in the Presence of Technical Iron Catalyst.]  Jour. Phys. Chem. (U.S.S.R.), vol. 11, 1938, pp. 569-577; Chem. Abs., vol. 33, 1939, p. 4386.

       Adsorption of N₂ and H₂ on technical catalyst 340 (composition is not disclosed) was investigated at –184° -425° and –184° -250°, respectively, at a constant pressure of 435 mm.  With H₂, a definite sorption process was observed in the region below 250° K. and another up to 500° K.  The energy of activation of the low-temperature process increased from 7,200 to 10,680 cal. per mol., with increase of surface from 0.5 to 3.5 cm.²  One type of N₂ sorption was observed.  The energy of activation of low-temperature adsorption of N₂ was calculated to be equal to 1,500 cal. per mol.  The difference in the catalytic activity of the previously described Fe-Mo catalyst cannot be explained by difference in the magnitude of total surface, since the variation of the latter was inverse to the variation in the catalytic activity.  The velocity of sorption process in the presence of this catalyst increased with the increase of the catalytic activity.  The velocity of formation of NH₃ at 375° was near that of sorption of N₂ under the same conditions.  The energy of activation of the synthesis was considerably lower than that of the sorption of N₂.