TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Catalyst: The catalyst contains 84-88 wt.% of iron, 8-10 wt.% of aluminum, 1-3 wt.% of manganese and 0.5-2 wt.% of potassium, and has surface area of 25-65 m2/g and particle size of 60-2000 microns. The precursor metal alloy contains 39 wt.% of iron, 59 wt.% of aluminum and 2 wt.% of manganese.Preparation (claimed): The catalyst is prepared by mixing iron and aluminum chips or powders, and copper chips or copper compound, and manganese compound together uniformly, to form a metal chips/powder mixture. The mixture is heated and melted under inert gas to form a molten metal alloy. The molten alloy is cooled to room temperature to form a precursor solid metal alloy. The solid metal alloy is pulverized to form catalyst precursor particles of particle size of 0.1-100 mm, containing 35-55 wt.% of iron, 40-60 wt.% of aluminum, 0-10 wt.% of copper and 1-15 wt.% of manganese. The precursor particles are extracted or leached using a caustic solution of 10-50% concentration at 50-90 degrees C for 50-150 minutes, to remove a major portion of aluminum to obtain base catalyst particles. The base catalyst particles are washed with deionized water to pH 7. Water is replaced with water-free ethanol, and the resulting base skeletal iron catalyst particles are temporarily stored in ethanol. The base catalyst particles are impregnated with a potassium promoter alcohol solution. The alcohol is removed by vacuum vaporization to obtain promoted skeletal iron catalyst containing 0.1-3 wt.% of potassium.Preferred Preparation: The molten metal alloy is cooled in less than 10 seconds to room temperature by quenching in water. The base catalyst is screened to a desired particle size in an alcohol medium, to prevent exposure of the catalyst particles to air. The potassium promoter is impregnated onto a base skeletal iron catalyst by mixing the catalyst with an organic potassium-containing alcohol solution, chosen from methanolic potassium hydroxide, ethanolic potassium hydroxide or ethanolic potassium carbonate, and then removing the alcohol solvent by vaporizing and drying. The potassium promoter solvent is evaporated at 40-80 degrees C and 100-500 mm Hg vacuum. The promoted skeletal iron catalyst is activated in a fixed bed reactor at hydrogen flow rate of 0.05-1 NL/g-cat/hour and 300-350 degrees C for 2-12 hours, and then mixed with the liquid reaction medium to form a slurry which is transferred into a slurry phase Fischer-Tropsch reactor. EXAMPLE - Iron and aluminum chips were mixed uniformly together with a small amount of manganese carbonate in weight ratio of 39:59:2 and heated in an electric-arc induction furnace under argon gas protection with constant stirring to form a molten metal alloy. The molten iron-aluminum-manganese alloy was rapidly cooled to room temperature by quenching in water. The resulting solid metal alloy was mechanically pulverized to 0.1-3 mm particle size to obtain catalyst precursor particles. The catalyst precursor particles were extracted and/or leached using 25% concentrated sodium hydroxide at 75 degrees C to remove a major portion of the aluminum. The leached particles were washed with deionized water, temporarily stored in ethanol and then mixed with potassium carbonate solution. Water and ethanol were vaporized to obtain skeletal iron particles. The particles were treated with hydrogen gas at 350 degrees C for 8 hours to activate the catalyst.    The iron catalyst was transferred into a slurry phase reaction medium for activity evaluation. The slurry phase Fischer-Tropsch reaction conditions were catalyst particle size of 0.044-0.074 mm, catalyst loading of 15 weight%, 270 degrees C and 2.5 MPa pressure. Conversion (in %) of carbon monoxide and hydrogen were 81.7 and 63.8, respectively. 1-2C hydrocarbon (0.052 g/g iron-hour), 3-4C (0.08 g/g iron-hour), 5C or more hydrocarbon (0.32 g/g iron-hour), 1C or more hydrocarbon (0.452 g/g iron-hour) and carbon dioxide (0.47 g/g iron-hour) were obtained.