| 摘要 |
506,064. Catalysts. JOHNSON, G. W. (I. G. Farbenindustrie Akt.-Ges.) Sept. 21, 1937, No. 25589. [Class 1 (i)] [Also in Group IV] Catalysts for the hydrogenation of carbon monoxide consist wholly or mainly of a sintered metal of the iron group to which is added an alkali compound which in aqueous solution has a neutral or acid reaction and which is practically undecomposed at temperatures up to 1000‹ C. Alkali compounds specified are alkali halides, e.g. potassium chloride or bromide or sodium chloride or fluoride, and phosphates such as monosodium or monopotassium phosphate. These may be added in amounts of 0À1 per cent or less by weight of the metal, but generally 0À5-15 per cent or more is used. The sintered metals may be prepared from metal powders or porous metals by heating above 500‹ C., e.g. at 700 to 1000‹ C., for so long that a visible decrease in volume takes place. The preparation is described in Specifications 474,448, 490,090, and 496,880. Other activating substances, e.g. alumina, silica, compounds of Cu, Ti, Mn, W, Mo, Cr, Th, Ce, Zr, or other rare earths, may also be added in minor proportions. The alkali compounds may be added before, after, or during the sintering or even to iron compounds before their reduction. In an example, iron powder obtained by decomposition of the carbonyl is mixed with 5 per cent of potassium chloride and the same weight of water, heated, pressed into pills, and treated with hydrogen for 4 hours at 850‹ C. Specification 312,717, [Class 1 (i)], also is referred to. |
