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 1937.    KOHLSCHÜTER, V., AND NÄGELI, A.  [Topochemical Reactions.  Formation of Carbon on Contact Substances.]  Helv. Chim. Acta, vol. 4, 1921, pp. 45-76; Chem. Abs., vol. 15, 1921, p. 2767.

        Study was made of the nature of the C deposited upon electrolytic films of Co, Ni, Fe, and Ag and upon powders of these metals by the reaction 2 CO=C+CO2, at about 500°.  The supporting metal upon which the catalytic metals are electrolytically deposited influences the amount of C formed, it being greater when the support is Pt, and less when it is Ag or Cu.  The nature of the catalytic metal determines specifically the method of deposition and the amount and the characteristics of the C.  In the case of smooth Co, Ni, and Ag deposits, the C is not deposited visibly upon the surface but in the interior of the metallic film and appears as an unweighable film when the metal is dissolved in acid.  In the case of Fe, however, the C forms a deep-black surface deposit.  Co affords the largest C deposit, then Ni, Fe, and Ag.  The C deposited on Co is strongly graphitic; on Ni also graphitic, but somewhat more easily oxidizable; on Fe more sooty, and still more easily oxidizable; and on Ag very small in amount an difficult to oxidize.  On dark, lusterless deposits the C is deposited visibly on the surface, as was the case with smooth deposits of Fe; and it is more easily oxidized than C deposited within the metallic layer.  The amount of C produced by metallic powders was large and almost inseparably associated with tine particles of the metal.