2609. ---------------.  [PERRIN, M.]  [Loss in Weight of a Fischer Nickel Catalyst During Reduction.]  Bull. soc. chim., 1949, No. 5-6, pp. 366-367.

    Fischer Ni catalysts were heated to 450° in streams of Ni and H₂; the losses in weight were virtually the same.  A very slow reaction was observed at 220°, probably corresponding to a structural change in the catalyst.  For a total loss of 28.5% of the initial weight of the catalyst, 21.4% was represented by H₂O and 4.85% by CO₂.  The deficit of 2.25% was logically attributed to a slow reduction of CO₂ into CH₄, which dissolved in the H₂ and thereby was not measurable.  In reducing the catalyst by successive steps of temperature maintained until the weight of the catalyst became constant, it was found that at 120° the loss in weight was rapid and virtually complete in 2 hr.; at 210° the loss was rapid at the beginning and then slow for about 50 hr.; at 360° the loss occurred in about 5 hr. and likewise at 450°.  The losses were respectively, 9.4, 12.6, 9.1, and 1.7.