| 摘要 |
<PICT:0658848/III/1> Iron catalysts for use in the catalytic conversion of carbon monoxide and hydrogen are obtained by subjecting iron oxide mixed with a small amount such as 2-8 per cent of carbon, and from 0.5-10 per cent of conventional promoters such as alkali metal compounds or the oxides of chromium, zinc, magnesium, manganese or rare earth metals, to combustion and sintering in an oxidizing atmosphere at 2200 DEG to 2500 DEG F., preferably followed by reduction in hydrogen at 600-1100 DEG F. The iron oxide may advantageously comprise sintered pyrites ash, from 2-15 per cent by weight of oxides of antimony, vanadium, manganese or copper or 25-50 per cent of aluminium oxide being incorporated prior to sintering with carbon. In the Figure, pyrites concentrate from bin 1 is roasted at 700-1200 DEG F. in furnace 5 to reduce the sulphur content and passed via lines 11 and 18 to a moving grate 21 and sintered at 2000-2300 DEG F. in an oxidizing gas drawn downwardly through the mass by suction pump 29, thus combusting the residual sulphur and sintering the oxide mass. The latter, collected at 33, passes via 37 to a crusher 39 and hence to a mixer 43 where 5 per cent by weight of coke and 5-10 per cent of water which may contain 0.5-3 per cent of potassium carbonate or fluoride, are added. The mixture is then subjected to combustion of carbon and consequent sintering on the moving grate 49, any portion of the layer being exposed to sintering temperature for about one minute. The oxidizing gas is drawn downwardly through the mass as before. The product is crushed to 30-200 microns size and reduced in conventional manner. |
