3365.     ----------------.  [TELEGIN, V. G., AND SIDOROV, N. V.]  [Siderite as a Catalyst for Ammonia Synthesis.]  Jour. Appl. Chem. (U.S.S.R.), vol. 12, 1939, pp. 1769-1774 (in French, p. 1774); Chem. Abs., vol. 34, 1940, p. 8,188.

        Bakal (Ural) siderite contained FeO, 38.50; Fe₂O₃, 1.60; Al₂O₃, 2.20; SiO₂, 2.80; MgO, 13.25; CaO, 0.92; CO₂, 38.70; As, none; P, 0.001; S, 0.12 (as sulfate), and H₂O, 1.15%.  The synthesis of NH₃ was attempted at normal pressure and under 300 atm.  The sample of siderite containing ferrous oxide was inactive at atmospheric pressure and only slightly active at 300 atm., while samples containing the catalyst in the form of ferric oxide were more active.  The highest activity was reached with a catalyst containing the Fe in the form of Fe₃O₄.  15 refs.