TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Process: The synthesis gas feed stream and suspension feed stream comprising the catalyst are fed continuously to a high shear mixing zone of the reactor system. The shearing forces exerted on the suspension in the mixing zone are sufficiently high that the gas feed stream is broken down into gas bubbles and/or irregularly shaped gas voids. The suspension having the gas bubbles is discharged from the mixing zone into the reactor vessel. The volumetric mass transfer rate is 2-10000, preferably 5-100, kg-moles/hour of carbon monoxide transferred per m3 of suspension. The mass transfer rate is 5x10(-3)-5x10(-6) kg-moles carbon monoxide transferred per m2 of bubble and/or irregularly shaped void surface area per hour. The suspension present in the mixing zone is less than 20 volume% of the suspension present in the reactor vessel. The kinetic energy dissipation rate in the mixing zone is 0.5-25 kW/m3, preferably 0.5-5 kW/m3, related to total volume of the suspension. The average residence time of the liquid phase of the suspension in the vessel is 10 minutes to 50 hours, preferably 1-30 hours. The shearing forces exerted on the suspension provide breakage of the feed stream into gas bubbles having diameter of 1 micron to 10 mm, preferably 30-300 microns. The irregularly shaped gas voids are transient in that they are coalescing and fragmenting on a time scale of up to 500 ms. The product suspension stream is continuously withdrawn from the tank reactor (reactor vessel) and a portion of the stream is recycled to the mixing zone through an external conduit having a pump. The suspension recycled to the mixing zone is cooled by heat exchanger positioned on the external conduit. An internal heat exchanger is positioned within the suspension in the reactor. A gas cap comprising unconverted synthesis gas, methane, carbon dioxide, water vapor, inert gas, gaseous higher hydrocarbon and vaporized liquid higher hydrocarbon is present in the tank reactor above the suspension level, and a gaseous exit stream is withdrawn from the gas cap. Portion(s) of the stream are recycled to mixing zone. 30-90%, preferably 50-90%, of the carbon monoxide is converted to hydrocarbon product.Preferred Apparatus: The reactor vessel is a tank reactor or a tubular loop reactor. The mixing zone comprises injector-mixing nozzle which is positioned at or near the top of the tank reactor.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Catalyst: The catalyst comprises cobalt on inorganic oxide support selected from silica, alumina, silica-alumina and zinc oxide. It preferably comprises cobalt and at least one metal selected from zirconium, titanium, ruthenium and chromium on silica, alumina or silica-alumina. The inorganic oxide support has surface area of less than 100 m2/g, preferably less than 25 m2/g. The catalyst comprises 2-50 weight% (wt.%), preferably 10-40 wt.% of cobalt on the support. The catalyst has particle size of 5-500 microns, preferably 5-30 microns. The suspension of the catalyst comprises less than 40 wt.%, preferably 10-20 wt.%, of catalyst particles. EXAMPLE - Activated cobalt-zinc oxide Fischer-Tropsch catalyst (20% w/w cobalt) (5 g) was transferred under an inert gas blanket to a 1 l stirred tank reactor containing 300 ml of squalane. The stirrer was turned on and a synthesis gas mixture (carbon monoxide 26.6%, nitrogen 20.2%, balance hydrogen) at a space velocity of 6000 hour-1 was admitted to the tank reactor and the system pressure was increased to 425 psig. Gas leaving the tank reactor was passed through a water cooled knock-out pot to a system pressure controller before exiting the system. The temperature was raised over a period of 4 hours to 195 degrees C and was then increased at a rate of 2 degrees C every 3 hours to 220 degrees C. The system was allowed to run under these conditions for a total on-stream time of 117 hours. The gas stream was then switched to a synthesis gas mixture containing carbon dioxide (carbon monoxide 26.3%, nitrogen 10.9%, carbon dioxide 9.2%, balance hydrogen) at a space velocity of 8000 hour-1 under pressure of 431 psig at 221 degrees C, for 229 hours. The cobalt/zinc oxide catalyst was stable in the presence of carbon dioxide. The carbon monoxide conversion and the selectivity of the catalyst were unchanged when carbon dioxide was introduced into the reactor. The conversion of carbon monoxide in the synthesis gas free of carbon dioxide was 42.7 mol%. The selectivity of the hydrocarbon product formed using the synthesis gas free of carbon dioxide was 90.3 mol%. In the presence of carbon dioxide, the figures were 42.4 mol% and 91.4 mol% respectively.