2848.     ---------------.  [ROELEN, O.]  [Determination of the Content of Free Metal in Catalysts.]  FIAT Reel K-20, frames 32-37, 1938; PB 70,211; TOM Reel 287.

        Co catalysts are not reduced completely; unreduced oxide and carbonate remain.  The determination of the proportion of reduced metal is based on the fact that only the reduced metal, when mixed with H₂SO₄, develops an equivalent amount of H₂, which is measured.  By determination of the total amount of Co used, the proportion of reduced metal can be calculated.  Care must be taken that the N₂ used for the catalyst is free from O₂ and that the H₂ adsorbed on the catalyst is sucked off beforehand in the vacuum.  Details, with sketch of apparatus.