J. Vandeloosdrecht et al., NICKEL-IRON CATALYSTS PREPARED BY HOMOGENEOUS DEPOSITION-PRECIPITATION OF CYANIDE COMPLEXES ON A TITANIA SUPPORT, Topics in catalysis, 2(1-4), 1995, pp. 29-43
Nickel-iron catalysts have been prepared by homogeneous deposition-pre
cipitation of complex nickel-iron cyanides on a titania support. The n
ickel-iron alloys obtained after calcination and reduction of the cyan
ide precursors were characterized by Mossbauer spectroscopy, high-temp
erature X-ray diffraction, and magnetic measurements. Fischer-Tropsch
experiments show remarkable results. Catalysts prepared from K3Fe(CN)(
6) and Na2Fe(CN)(5)NO cyanide precursors exhibit a high activity and s
electivity, whereas catalysts prepared from K4Fe(CN)(6) do not show an
y activity. This lack of activity is caused by the presence of potassi
um in catalysts prepared from K4Fe(CN)(6). Potassium or iron titanate
inhibits the adsorption of CO on the nickel-iron surface. Deactivation
of active nickel-iron catalysts was caused by the deposition of inact
ive carbon during Fischer-Tropsch synthesis.