(EP935497-A1)      A catalytic composition comprises an inert carrier, 1-50 wt.% cobalt and 0.05-5 wt.% tantalum, the elements being in metal form or as a derivative.The preparation of the composition involves: (a) a first deposition of cobalt salt onto the inert carrier, preferably silica and/or alumina, followed by calcination to give a catalytic precursor and optionally reduction and passivation; and (b) deposition onto the precursor of a derivative of tantalum, followed by calcination and optionally reduction and passivation. The synthesis of linear and saturated hydrocarbons from synthesis gas of carbon monoxide and hydrogen, possibly diluted with nitrogen, involves reacting this mixture in the present of the above catalytic composition at 150-350C, pressure 1-100 bars and molar ratio of hydrogen/carbon monoxide of 1:2-5:1.    USE -   For use as catalyst in the synthesis of linear saturated hydrocarbons from synthesis gas, especially the Fischer-Tropsch process.    ADVANTAGE -   The catalyst composition has high productivity for hydrocarbons and low selectivity to methane.    (CN1230902-A)      A catalytic composition comprises an inert carrier, 1-50 wt.% cobalt and 0.05-5 wt.% tantalum, the elements being in metal form or as a derivative.The preparation of the composition involves: (a) a first deposition of cobalt salt onto the inert carrier, preferably silica and/or alumina, followed by calcination to give a catalytic precursor and optionally reduction and passivation; and (b) deposition onto the precursor of a derivative of tantalum, followed by calcination and optionally reduction and passivation. The synthesis of linear and saturated hydrocarbons from synthesis gas of carbon monoxide and hydrogen, possibly diluted with nitrogen, involves reacting this mixture in the present of the above catalytic composition at 150-350C, pressure 1-100 bars and molar ratio of hydrogen/carbon monoxide of 1:2-5:1.    USE -   For use as catalyst in the synthesis of linear saturated hydrocarbons from synthesis gas, especially the Fischer-Tropsch process.    ADVANTAGE -   The catalyst composition has high productivity for hydrocarbons and low selectivity to methane.    (ZA9809266-A)      A catalytic composition comprises an inert carrier, 1-50 wt.% cobalt and 0.05-5 wt.% tantalum, the elements being in metal form or as a derivative.The preparation of the composition involves: (a) a first deposition of cobalt salt onto the inert carrier, preferably silica and/or alumina, followed by calcination to give a catalytic precursor and optionally reduction and passivation; and (b) deposition onto the precursor of a derivative of tantalum, followed by calcination and optionally reduction and passivation. The synthesis of linear and saturated hydrocarbons from synthesis gas of carbon monoxide and hydrogen, possibly diluted with nitrogen, involves reacting this mixture in the present of the above catalytic composition at 150-350C, pressure 1-100 bars and molar ratio of hydrogen/carbon monoxide of 1:2-5:1.    USE -   For use as catalyst in the synthesis of linear saturated hydrocarbons from synthesis gas, especially the Fischer-Tropsch process.    ADVANTAGE -   The catalyst composition has high productivity for hydrocarbons and low selectivity to methane.    (US6075062-A)      A catalytic composition comprises an inert carrier, 1-50 wt.% cobalt and 0.05-5 wt.% tantalum, the elements being in metal form or as a derivative.The preparation of the composition involves: (a) a first deposition of cobalt salt onto the inert carrier, preferably silica and/or alumina, followed by calcination to give a catalytic precursor and optionally reduction and passivation; and (b) deposition onto the precursor of a derivative of tantalum, followed by calcination and optionally reduction and passivation. The synthesis of linear and saturated hydrocarbons from synthesis gas of carbon monoxide and hydrogen, possibly diluted with nitrogen, involves reacting this mixture in the present of the above catalytic composition at 150-350C, pressure 1-100 bars and molar ratio of hydrogen/carbon monoxide of 1:2-5:1.    USE -   For use as catalyst in the synthesis of linear saturated hydrocarbons from synthesis gas, especially the Fischer-Tropsch process.    ADVANTAGE -   The catalyst composition has high productivity for hydrocarbons and low selectivity to methane.    (JP2001500430-W)      A catalytic composition comprises an inert carrier, 1-50 wt.% cobalt and 0.05-5 wt.% tantalum, the elements being in metal form or as a derivative.The preparation of the composition involves: (a) a first deposition of cobalt salt onto the inert carrier, preferably silica and/or alumina, followed by calcination to give a catalytic precursor and optionally reduction and passivation; and (b) deposition onto the precursor of a derivative of tantalum, followed by calcination and optionally reduction and passivation. The synthesis of linear and saturated hydrocarbons from synthesis gas of carbon monoxide and hydrogen, possibly diluted with nitrogen, involves reacting this mixture in the present of the above catalytic composition at 150-350C, pressure 1-100 bars and molar ratio of hydrogen/carbon monoxide of 1:2-5:1.    USE -   For use as catalyst in the synthesis of linear saturated hydrocarbons from synthesis gas, especially the Fischer-Tropsch process.    ADVANTAGE -   The catalyst composition has high productivity for hydrocarbons and low selectivity to methane.