PROCESS FOR CONVERTING SYNTHESIS GAS TO HIGHER ALCOHOLS

Abstract

The present invention refers to a process for converting a feed gas stream comprising carbon monoxide and hydrogen as major components (synthesis gas) into higher (C.sub.3+) alcohols making use of a catalyst combination of a Fischer-Tropsch catalyst and an olefin hydroformylation catalyst. In a second aspect, the invention relates to a Fischer-Tropsch catalyst suitable to be applied in said process.

Claims

1. A process for converting a syngas feed stream into C.sub.3+ alcohols, said process comprising: in a first step, contacting a syngas feed stream comprising carbon monoxide and hydrogen with a H.sub.2/CO ratio in the range of 0.4 to 4.0 in a solvent in a single reactor in a temperature range of 298 K to 533 K under a reaction pressure of 1 bar to 300 bar with a catalyst combination comprising: (i) a Fischer-Tropsch catalyst as a first catalyst, which converts syngas to a hydrocarbon mixture comprising C.sub.2+ olefins and which is essentially inactive for a water-gas-shift reaction, wherein the Fischer-Tropsch catalyst is a supported metal catalyst comprising a metal selected from Co, Ru or a combination thereof is-supported on a porous carrier selected from oxide carriers selected from Al.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, or any combination thereof, carbide or oxy-carbide materials selected from SiC, SiO.sub.xC.sub.y, with x being in the range of 0<x<2 and y in the range of 0<y<1, pure carbon or any combination thereof; and (ii) a hydroformylation catalyst as a second catalyst, which is stable and active for thea reductive hydroformylation of olefins and which is highly selective for the production of terminal alcohols, wherein the hydroformylation catalyst comprises (i) a metal selected from cobalt, ruthenium, rhodium, iridium, or any combination thereof and (ii) at least one organic ligand from oxygen-containing ligands, phosphorus-containing ligands, nitrogen-containing ligands, arsenic-containing ligands and combinations thereof and which binds to the metal to form a coordination complex in a molar ratio ligand/metal of 1:1 to 5:1; in a ratio between the Fischer-Tropsch catalyst and the hydroformylation catalyst, expressed as a molar ratio of total metal in the Fischer-Tropsch catalyst and the-total metal in the hydroformylation catalyst in the range of 30:1-1:4, and, in a second step, recovering C.sub.3+ alcohols formed as reaction products from the reactor.

2. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein the Fischer-Tropsch catalyst has an activity for the Fischer-Tropsch synthesis expressed as a metal mass-specific rate of CO conversion, being equal to or higher than 5 mmol.sub.CO g.sub.metal.sup.?1h.sup.?1, wherein the Fischer-Tropsch catalyst delivers a selectivity to CO.sub.2 equal to or lower than 5% on a carbon basis, and a molar abundance of alpha-olefin hydrocarbons in the hydrocarbon products with hydrocarbon chain lengths in the range of C.sub.3-C.sub.10 which is equal to or greater than 30% on a carbon basis, when a syngas feed with a H.sub.2/CO molar ratio of 2.0 is contacted with the Fischer-Tropsch catalyst at a reaction temperature equal to or lower than 483 K, and a reaction pressure equal to or greater than 15 bar and a CO conversion achieved in the reactor is greater than 15%.

3. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein the porous carrier comprises mesopores and macropores.

4. Process for converting a syngas feed stream into C.sub.3+ alcohols according toclaim 1, wherein the Fischer-Tropsch catalyst additionally comprises a first metal promoter selected from rhenium, platinum, palladium, silver, gold, and copper.

5. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 4, wherein the Fischer-Tropsch catalyst additionally comprises a second promoter selected from alkali metals, alkaline earth metals, transition metals (other than rhenium, platinum, palladium, silver, gold and copper, boron, aluminium, gallium, indium, carbon, silicon, germanium, tin, nitrogen, phosphorous, arsenic, antimony, lanthanides, or any combination thereof, whereby said second promoter is present in elementary form or in ionic form as a salt.

6. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein a hydroformylation catalyst is used as a second catalyst.

7. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein a hydroformylation catalyst is used which is prepared by reacting, in an organic solvent, at least one metal precursor compound selected from carbonyl complexes or salts of cobalt, ruthenium, rhodium, iridium, or any combination thereof, with at least one organic ligand which binds to the metal to form a coordination complex.

8. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein the reactor is operated in a batch mode.

9. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 1, wherein the reactor is operated in a continuous mode, wherein at least one stream of the gas feed and one stream of the solvent are provided continuously to the reactor inlet and a product stream is continuously removed at the outlet of the reactor.

10. A catalyst combination for converting a syngas feed into C.sub.3+ alcohols comprising: (i) a Fischer-Tropsch catalyst as a first catalyst, which converts syngas to a hydrocarbon mixture comprising C.sub.2+ olefins and which is essentially inactive for a water-gas-shift reaction, wherein the Fischer-Tropsch catalyst is a supported metal catalyst comprising a metal selected from Co, Ru or a combination thereof supported on a porous carrier selected from oxide carriers selected from Al.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, or any combination thereof, carbide or oxy-carbide materials selected from SiC, SiO.sub.xC.sub.y, with x being in the range of 0<x<2 and y in the range of 0<y<1, pure carbon or any combination thereof; and (ii) a hydroformylation catalyst as a second catalyst, which is stable and active for a reductive hydroformylation of olefins and which is highly selective for the production of terminal alcohols, wherein the hydroformylation catalyst comprises (i) a metal selected from cobalt, ruthenium, rhodium, iridium, or any combination thereof and (ii) at least one organic ligand selected from oxygen-containing ligands, phosphorus-containing ligands, nitrogen-containing ligands, arsenic-containing ligands, and combinations thereof and which binds to the metal to form a coordination complex in a molar ratio ligand/metal of 1:1 to 5:1; in a ratio between the Fischer-Tropsch catalyst and the hydroformylation catalyst, expressed as a molar ratio of metal in the Fischer-Tropsch catalyst and the metal in the hydroformylation in a range of 30:1-1:4.

11. (canceled)

12. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 3, wherein the volume of macropores accounts for at least a 5 Vol.-% of the total pore volume

13. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 12, wherein the volume of macropores accounts for at least a 20 Vol.-% of the total pore volume.

14. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 4, wherein the weight content of the first promoter is larger than 0 wt % and lower than 10 wt %, calculated on a basis of a total mass of the Fischer-Tropsch catalyst.

15. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 14, wherein the weight content of the first promoter is larger than 0 wt % and lower than 2 wt %, calculated on the basis of the total mass of the Fischer-Tropsch catalyst.

16. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 5, wherein the weight content of the second promoter is larger than 0 wt % and lower than 50 wt %, calculated on a basis of the total mass of the Fischer-Tropsch catalyst.

17. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 16, wherein the weight content of the second promoter is larger than 0wt % and lower than 20 wt %, calculated on the basis of the total mass of the Fischer-Tropsch catalyst.

18. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 7, wherein the carbonyl complexes or salts are selected from formate, acetate, acetylacetonate, carboxylate, carbonate, oxalate, halide, amine, imide, and any combination thereof, and/or the at least one organic ligand is selected from and is selected from the group of oxygen-containing ligands, phosphorus-containing ligands, nitrogen-containing ligands, arsenic-containing ligands and combinations thereof.

19. Process for converting a syngas feed stream into C.sub.3+ alcohols according to claim 18, wherein the at least one organic ligand is a phosphorus-containing ligand.

20. Catalyst combination according to claim 10, wherein the molar ratio of metal in the Fischer-Tropsch catalyst and metal in the hydroformylation is in a range of 10:1-1:2.

21. Catalyst combination according to claim 20, wherein the molar ratio of metal in the Fischer-Tropsch catalyst and metal in the hydroformylation is in a range of 4:1-1:1.

Description

[0105] The present invention will now be described in more detail by means of the following Figures and Experimental Part.

[0106] In the Figures:

[0107] FIG. 1 shows the cumulative intrusion isotherm (full symbols, left y-axis) and the pore size distribution (open symbols, right axis) as determined by mercury intrusion porosimetry for catalyst CoRu/Al.sub.2O.sub.3m _. The abscissa x-axis reports the pore size in nanometers, increasing from left to right and with a 10-logarithmic scale. The left ordinates y-axis reports the cumulative mercury intrusion volume, increasing from bottom to top, with a linear scale. The right y-axis reports the log differential pore volume, increasing from bottom to top, with a linear scale, and

[0108] FIG. 2 shows the cumulative intrusion profile (full symbols, left y-axis) and the pore size distribution (open symbols, right axis) as determined by mercury intrusion porosimetry for catalyst CoRu/Al.sub.2O.sub.3mM. The abscissa x-axis reports the pore size in nanometers, increasing from left to right and with a 10-logarithmic scale. The left ordinates y-axis reports the cumulative mercury intrusion volume, increasing from bottom to top, with a linear scale. The right y-axis reports the log differential pore volume, increasing from bottom to top, with a linear scale. In both FIG. 1 and FIG. 2, peaks in pore size distribution at pore diameters higher than 10000 nm correspond to voids between the catalyst particles.

EXPERIMENTAL PART

Methods for Determining the Properties of the Materials

[0109] The following methods were employed for determining the properties of materials as prepared and used in the Examples listed herein below:

[0110] Macropore and mesopore size distributions, as well as total macropore volumes of solid materials were determined by means of mercury intrusion porosimetry in a Micromeritics AutoPore IV 951 apparatus. In a typical experiment, 80-150 mg of sample (<0.08 mm) were dried at 383 K for 72 h before the measurement. The intrusion-extrusion isotherms were recorded at room temperature in the pressure range of 1.01-59848 psia with an equilibration rate of 0.1 ?L g.sup.?1s.sup.?1. For the determination of pore diameter and volume, a cylindrical pore model was considered, with a Hg density of 13.55 g cm.sup.?3 and a contact angle of 141?. Pore size distributions were visualized by plotting the logarithmic differential volume intrusion (dV/dlogD) versus the equivalent pore diameter expressed in nanometers.

[0111] Specific surface area of solid materials was determined by means of nitrogen physisorption. Nitrogen physisorption isotherms were recorded using a Micromeritics ASAP instrument after degassing the sample (ca. 100 mg, <0.08 mm particle size) at 523 K under vacuum for 10 h. Surface areas were derived using the B.E.T method in the relative pressure (P/P.sub.0) regime of 0.05-0.30. Total mesopore volumes were based on the amount of N.sub.2 adsorbed at a relative pressure P/P.sub.0=0.95.

[0112] The macroscopic particle size of solid materials was adjusted and determined using calibrated Retsch stainless steel sieves.

[0113] The cobalt metal loading in cobalt-based Fischer-Tropsch catalysts was determined by means of hydrogen temperature-programmed reduction (H.sub.2-TPR) in a Micromeritics Autochem 2910 device. In a typical experiment, about 100 mg of sample were initially flushed with Ar flow (50 cm.sup.3 min.sup.?1) at room temperature for 30 min, then the gas was switched to 10 vol % H.sub.2 in argon (Ar) and the temperature increased up to 1123 K at a heating rate of 10 K min.sup.?1. A downstream 2-propanol/dry ice trap was used to retain the water generated during the reduction. The H.sub.2 consumption rate was monitored in a thermal conductivity detector (TCD) previously calibrated via the injection of known volumes of hydrogen using a gas syringe. The cobalt loading was determined from the total hydrogen consumption assuming all cobalt to be present as Co.sub.3O.sub.4 in the calcined catalysts, i.e. prior to the H.sub.2-TPR experiment, and full reduction to metallic cobalt, which results in a reduction stoichiometric H.sub.2/Co molar ratio of 4/3. The hydrogen consumption associated to the Ru promoter was considered negligible. The cobalt metal content in the cobalt-based hydroformylation catalyst was determined by direct weighing of the corresponding cobalt precursor of known molecular formula.

Synthesis of Catalysts According to the Current Invention

[0114] Synthesis of a Fischer-Tropsch catalyst according to the invention (CoRu/Al.sub.2O.sub.3_m) An Al.sub.2O.sub.3 support material with a pore size distribution with a major contribution in the mesopore range (peak at 6.8 nm, FIG. 1), and a minor contribution in the macropore range (peak at 1081 nm, FIG. 1) denoted hereafter as Al.sub.2O.sub.3_m, was prepared by submitting commercial powder pseudo-boehmite (Catapal B, from Sasol Materials) to a thermal treatment at 823 K for 5 hours in a muffle oven under stagnant air atmosphere. The resulting Al.sub.2O.sub.3 was pressed into self-supported wafers, crushed and sieved to retain particles in the size range of <0.08 mm. To synthesize the Fischer-Tropsch catalyst, the Al.sub.2O.sub.3 particles were first dried under dynamic vacuum (rotatory pump) at 423 K for 2 hours. Subsequently, the dry solid was impregnated under static vacuum with an aqueous solution containing Co(NO.sub.3).sub.2.Math.6H.sub.2O (1.5 M, Sigma-Aldrich, ?98%, CAS: 10026-22-9) and ruthenium (III) nitrosyl nitrate (in dilute nitric acid, Sigma-Aldrich, CAS: 34513-98-9), previously prepared to have an atomic ratio Ru/Co=0.007, and further acidified with 0.25 vol % HNO.sub.3(69-70 vol. % in H.sub.2O, J. T. Baker, ?99%, CAS: 7697-37-2). The volume of solution infiltrated in the Al.sub.2O.sub.3 support was equivalent to 90% of the total mesopore volume of the support as determined by N.sub.2 physisorption. After impregnation, the solid was dried in the form of a packed bed in a tubular reactor at 343 K under vertical downward N.sub.2 flow (200 cm.sup.3 g.sub.cat.sup.?1min.sup.?1, Air Liquide, 99.9999%, CAS: 7440-37-1) for 10 hours and the nitrate precursors were further decomposed at 623 K for 4 h under the N.sub.2 flow (heating rate of 1 K min.sup.?1). This impregnation, drying and decomposition procedure was repeated four times. For each impregnation step beyond the first one, the total mesopore volume was corrected by the volume of the metal species previously deposited in the pores, assuming a density of 6.1 cm.sup.3 g.sup.?1 (Co.sub.3O.sub.4). Finally, the catalyst was subjected to a thermal reduction treatment, after having placed it in the form of a packed bed inside a tubular reactor, in H.sub.2 flow (200 cm.sup.3 STP min.sup.?1, Air Liquide, 99.9999%, CAS: 1333-74-0) at 673 K (2 K min.sup.?1 to 423 K, followed by 0.83 K min.sup.?1 to 673 K) for 5 h at atmospheric pressure, and then transferred and stored in a glove box, under exclusion of oxygen and water, until its further application in the inventive process. According to mercury intrusion porosimetry results, the fraction of the total pore volume which corresponds to macropores with diameters in the size range from 50 nm to 5 ?m in the catalyst is 29% of the total volume of pores with diameters in the size range from 5 nm to 5 ?m.

Synthesis of a Fischer-Tropsch Catalyst According to the Invention (CoRu-NaPr/Al.SUB.2.O.SUB.3._mM)

[0115] An Al.sub.2O.sub.3 support material with a pore size distribution with similar contributions in the mesopore (peak at 10.7 nm in FIG. 2) and macropore ranges (peak at 1989 nm in FIG. 2), denoted hereafter as Al.sub.2O.sub.3_mM, was synthesized by calcination of a commercial microparticulate ?-Al.sub.2O.sub.3 (Versal, UOP) under a stagnant air atmosphere in a muffle oven at 823 K using a 0.5 K min.sup.?1 heating rate from room temperature and sieving the resulting solid to retain particles in the size range of <0.08 mm mm. The Al2O3 granules were first dried under dynamic vacuum (rotatory pump) at 423 K for 2 hours. Subsequently, the dry solid was impregnated under static vacuum with an aqueous solution containing Co(NO.sub.3).sub.2.Math.6H.sub.2O (1.5 M, Sigma-Aldrich, ?98%, CAS: 10026-22-9) and ruthenium (III) nitrosyl nitrate (in dilute nitric acid, Sigma-Aldrich, CAS: 34513-98-9) previously prepared to have an atomic ratio Ru/Co=0.007, and further acidified with 0.25 vol % HNO.sub.3 (69-70 vol. % in H.sub.2O, J. T. Baker, ?99%, CAS: 7697-37-2). The volume of solution infiltrated in the Al.sub.2O.sub.3 support was equivalent to 90% of the total mesopore volume of the support as determined by N.sub.2 physisorption. After impregnation, the solid was dried in the form of a packed bed in a tubular reactor at 343 K under vertical downward N.sub.2 flow (200 cm.sup.3 g.sub.cat.sup.?1min.sup.?1, Air Liquide, 99.9999%, CAS: 7440-37-1) for 10 hours and the nitrate precursors were further decomposed at 623 K for 4 h under the N.sub.2 flow (heating rate of 1 K min.sup.?1). This impregnation, drying and decomposition procedure was repeated once. Then, the aqueous solution containing Co(NO.sub.3).sub.2.Math.6H.sub.2O (1.5 M) and ruthenium (III) nitrosyl nitrate (in dilute nitric acid), previously prepared to have an atomic ratio Ru/Co=0.007, and further acidified with 0.25 vol % HNO.sub.3 (69-70 vol. % in H.sub.2O) was diluted with 50wt % 0.5 M HNO.sub.3. This solution was used for a third impregnation step, again filling 90% of the total mesopore volume of the support as determined by N.sub.2 physisorption, followed by the drying and decomposition steps, as described above to produce a CoRu/Al.sub.2O.sub.3 material. For each impregnation step beyond the first one, the total mesopore volume was corrected by the volume of the metal species previously deposited in the pores, assuming a density of 6.1 cm.sup.3g.sup.?1 (C0304).

[0116] Next, the as-calcined CoRu/Al.sub.2O.sub.3 material was dried as detailed above, and further impregnated by slurring it in an aqueous solution of the praseodymium (Pr) and sodium (Na) salts in order to introduce both Pr and Na as promoters. For each 1 g of CoRu/Al.sub.2O.sub.3 material to impregnate, 11.1 cm.sup.3 of an aqueous solution containing 115.6 mg of Pr(NO.sub.3).sub.3.Math.6H.sub.2O (Sigma-Aldrich, 99.9%, CAS: 15878-77-0) and 5.7 mg NaNO.sub.3 NaNO.sub.3 (Sigma-Aldrich, >99%, CAS: 7631-99-4) dissolved in 0.5 M HNO.sub.3 were applied in this impregnation step. After slurring the solid in the impregnating solution under shaker stirring, water was removed in a rotary evaporator at 323 K and the resulting dry solid was transferred to a tubular reactor, packed in the form of a packed bed and calcined at 623 K for 4 h under vertical downward synthetic air flow (Air Liquide, 20.5?0.5 mol % O.sub.2 in N.sub.2, 99.999%, CAS: 132259-10-0) using a heating rate of 1 K min.sup.?1 from room temperature and a gas flow of 200 cm.sup.3 g.sub.solid.sup.?1 min.sup.?1. Finally, the catalyst was subjected to a thermal reduction treatment, after having placed it in the form of a packed bed inside a tubular reactor, in H.sub.2 flow (200 cm.sup.3 STP min.sup.?1, Air Liquide, 99.9999%, CAS: 1333-74-0) at 673 K (2 K min.sup.?1 to 423 K, followed by 0.83 K min.sup.?1 to 673 K) for 5 h at atmospheric pressure, and then transferred and stored in a glove box, under exclusion of oxygen and water, until its further application in the inventive process. According to mercury intrusion porosimetry results, the fraction of the total pore volume which corresponds to macropores with diameters in the size range from 50 nm to 5 ?m in the catalyst is 63% of the total volume of pores with diameters in the size range from 5 nm to 5 ?m.

General Method I to Integrate Catalyst and Perform a Reaction Test According to the Inventive Process

[0117] In a general method of this invention, pre-set amounts of (i) the Fischer-Tropsch catalyst, (ii) a metal precursor for the hydroformylation catalyst, (iii) one or various organic compounds as ligand for the development of the hydroformylation catalysts, and (iv) a solvent, are added under an inert atmosphere, that is under the exclusion of oxygen and moisture, into a 10 mL borosilicate glass inlet in order: first (i), then (ii), (iii) and finally (iv). 50 mg of iso-octane (Sigma Aldrich, 98%) are added as internal standard for gas chromatography analysis. The glass-inlet is transferred inside a 12 mL stainless-steel autoclave discontinuous reactor equipped with a magnetic stirrer and the reactor is sealed under exclusion of air and moisture. Next, the reactor is flushed at least twice with 120 bar of a certified syngas mixture of H.sub.2:CO:Ar with a molar composition 60:30:10 (Air Liquide) fed from a single pressurized gas cylinder. Finally, the reactor is pressurized to a total pressure of 120 bar, at room temperature, with the same syngas mixture. The reaction of conversion of syngas is then conducted by inserting the reactor in an aluminium heat distributor block on a heating-stirring plate preheated at 468 K and the stirring speed is set to 700 rpm. After a predefined reaction time, the reaction is quenched by letting the reactor cool down to room temperature inside a water bath.

General Method II to Integrate Catalyst and Perform a Reaction Test According to the Inventive Process

[0118] In another general method of this invention, pre-set amounts of (i) a solution of a metal precursor for the hydroformylation catalyst in the solvent, and (ii) a solution of one or various organic compounds as ligand for the development of the hydroformylation catalysts in the solvent, are added under an inert atmosphere, that is under the exclusion of oxygen and moisture, into a 10 mL borosilicate glass inlet in order: first (i), then (ii). 50 mg of iso-octane (Sigma Aldrich, 98%) are added as internal standard for gas chromatography analysis. The glass-inlet is transferred inside a 12 mL stainless-steel autoclave discontinuous reactor equipped with a magnetic stirrer and the reactor is sealed under exclusion of air and moisture. Next, the reactor is flushed at least twice with 120 bar of a certified syngas mixture of H.sub.2:CO:Ar with a molar composition 60:30:10 (Air Liquide) fed from a single pressurized gas cylinder. Next, the reactor is pressurized to a total pressure of 120 bar with the same syngas mixture, and it is inserted in an aluminium heat distributor block on a heating-stirring plate preheated at 468 K and the stirring speed is set to 700 rpm. After 1 hour, the reactor is cooled to room temperature using a water bath and gas is released from the reactor to lower the total pressure to 2 bar. Then the reactor is transferred inside a glove box with an inert atmosphere, that is under exclusion of oxygen and moisture, and the remaining gas inside the reactor is released, the reactor is opened and a pre-set amount of the Fischer-Tropsch catalyst is added into the glass liner. Then the reactor is re-filled and pressurized with a certified syngas mixture of H.sub.2:CO:Ar with a molar composition 60:30:10 up to a total pressure of 120 bar at room temperature. The reaction of conversion of syngas is then conducted by inserting the reactor in an aluminium heat distributor block on a heating-stirring plate preheated at 468 K and the stirring speed is set to 700 rpm. After a predefined reaction time, the reaction is quenched by letting the reactor cool down to room temperature inside a water bath.

General Method to aAnalyze the roducts of a Reaction of Syngas Conversion According to the Inventive Process

[0119] After terminating the reaction of conversion of syngas, a portion of the gas phase inside the reactor was released to flush and fill two sampling loops, connected in series, of an Agilent 7890B gas chromatograph (GC). One of the sampling loops is injected into a capillary column (Restek RTX-1, 60 m) which elutes into an Flame Ionization detector (FID). The other sampling loop is injected into two consecutive packed-bed columns (HS-Q 80/120, 1?m+1?3 m) in series, which elute into a Thermal Conductivity detector (TCD) for the analysis of H.sub.2, CO.sub.2, and C.sub.2-C.sub.3 hydrocarbons. Along the same analysis channel, a molecular sieve column (13X) is used for the separation of Ar, CH.sub.4, andCO permanent gases, which are detected using an additional TCD. After sample injection, the GC oven temperature is kept at 308 K for 10 min, after that the oven is heated to 483 K (with a heating ramp of 283 K min.sup.?1), after which the temperature was kept at 483 K for 45 min. CO, CH.sub.4, and CO.sub.2 were quantified using TCD response factors relative to Ar, whereas C2+ hydrocarbons and alcohols were quantified in the FID relative to CH.sub.4.

[0120] Condensed phases in the reactor after the reaction test are collected and then centrifuged in an ultracentrifuge at 14.000 rpm, and the liquid and solid phases separated and recovered separately. The resulting liquid sample is injected into an Agilent 7890B gas chromatograph equipped with a capillary column (Restek RTX-1, 60 m) which elutes into an FID. Following injection, the GC oven temperature was increased from room temperature to 493 K at a heating rate of 278 K min.sup.?1, after which temperature was kept at 493 K for 50 min. Hydrocarbons and alcohols were quantified based on their FID signal relative to iso-octane as standard.

[0121] The amount of wax hydrocarbons contained in the solid pellet recovered after centrifugation are quantified by thermogravimetric analysis (TGA) in air using a corundum crucible inside a Netzsch Jupiter STA 449 C thermobalance and applying a heating ramp of 283 K min.sup.?1 from 298 K to 1023 K. The fraction of the total amount of combusted matter associated to waxy hydrocarbon reaction products was determined by subtracting contributions from (i) the release of CO ligands in Co(CO).sub.8 on the basis of the cobalt carbonyl stoichiometry, the Co/Al stoichiometry in the Fischer-Tropsch catalyst and the total cobalt content in the inorganic residue left behind in the crucible after the TGA experiment as determined by energy-dispersive X-ray analysis (EDX) in a Hitachi S-3500N scanning electron microscope equipped with an Oxford Instruments EDS; and (ii) the combustion of organic ligands from the hydroformylation catalyst as determined from the total phosphorous content in the ligand and the ligand-to-cobalt stoichiometry in the molecular hydroformylation catalyst.

EXAMPLES

Example 1

[0122] In one example according to the inventive process, 30.5 mg of CoRu/Al.sub.2O.sub.3_m was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 9.0 mg Co.sub.2(CO).sub.8 as metal precursor and 14.7 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Example 2

[0123] In another example according to the inventive process, 41.5 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 24.0 mg Co.sub.2(CO).sub.8 as metal precursor and 39.2 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Example 3

[0124] In another example according to the inventive process, 39.7 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 19.6 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Example 4

[0125] In another example according to the inventive process, 43.4 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 19.6 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Example 5

[0126] In another example according to the inventive process, 40.0 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 18.5 mg P(Ph).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II. The abbreviation P(Ph).sub.3 stands for tri-phenyl phosphine.

Example 6

[0127] In another example according to the inventive process, 41.3 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 23.9 mg Co.sub.2 (CO).sub.8 as metal precursor and 39.2 mg P(Cy).sub.3 as organic ligand. 1.0 mL of iso-pentane (2-methylbutane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method I.

Example 7

[0128] In another example according to the inventive process, 41.8 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 15.0 mg P(n-Bu).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II. The abbreviation P(n-Bu).sub.3 stands for tri-n-butyl phosphine.

Example 8

[0129] In another example according to the inventive process, 40.2 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 19.6 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. The reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Comparative Example CP 1

[0130] In a comparative example not according to the inventive process, 40.7 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. As a hydroformylation catalyst only 12.0 mg Co.sub.2(CO).sub.8 were added to the reaction pot, without the addition of any organic ligand component. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. Otherwise, the reaction integration of the catalysts and the syngas conversion reaction test were performed according to the general method II.

Comparative Example CP 2

[0131] In a comparative example not according to the inventive process, 40.0 mg of CoRu-NaPr/Al.sub.2O.sub.3_mM was applied as Fischer-Tropsch catalyst. No hydroformylation catalyst was added to the reaction pot. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. Otherwise, the syngas conversion reaction test were performed according to the general method I.

Comparative Example CP 3

[0132] In a comparative example not according to the inventive process, no Fischer-Tropsch catalyst was added to the reaction pot. The hydroformylation catalyst was developed from 12.0 mg Co.sub.2(CO).sub.8 as metal precursor and 14.1 mg P(Cy).sub.3 as organic ligand. 1.37 mL of iso-hexane (2-methylpentane) was applied as solvent. Otherwise, the syngas conversion reaction test were performed according to the general method II.

TABLE-US-00001 TABLE 1 Selectivity Selectivity Time-yield T.sup.a Time.sup.b X.sub.co.sup.c CO.sub.2 C.sub.3+-ROH.sup.d C.sub.3+-ROH.sup.e ?.sub.ROH.sup.f Example (K) (h) (%) (%) (%) (mg/g.sub.co .Math. h.sup.?1) () 1 473 24 24.5 1.1 32.2 93.6 0.66.sup.g 2 473 24 31.0 1.5 44.3 80.0 0.65 3 473 24 27.6 1.9 47.5 77.0 0.67 4 473 32 45.8 1.1 47.8 132.5 0.75.sup.g 5 473 24 28.8 2.3 44.8 104.3 0.65 6 473 24 32.3 1.5 47.0 99.4 0.77 7 473 24 26.8 4.9 51.3 113.3 0.69 8 473 48 47.9 2.7 48.1 82.3 0.68 CP 1 473 24 41.8 1.6 18.1 62.8 0.60 CP 2 473 24 36.1 1.5 24.2 79.0 0.61 CP 3 473 24 0.2 ?60 0.0 0.0 .sup.aTemperature; .sup.bReaction time; .sup.cConversion of CO; .sup.dSelectivity to higher alcohols with three or more carbon atoms (C.sub.3+-ROH); .sup.eCobalt mass-specific time-yield to higher alcohols with three or more carbon atoms; .sup.fAnderson-Schulz-Flory chain-growth probability for alcohols as determined for alcohol products in the chain length range of 3-8 carbon atoms, unless otherwise stated. .sup.gDetermined for alcohol products in the chain length range of 4-9 carbon atoms.

[0133] As it can be seen from the results presented in Table 1, the inventive examples illustrate a process whereby syngas is converted to alcohols with high selectivity and time-yield. Under otherwise identical process conditions, the application of a solvent which is under supercritical conditions at the applied process conditions, such as iso-pentane (2-methylbutane, with critical temperature T.sub.c=461 K, critical pressure P.sub.c=33 bar) in Example 6, leads to enhanced selectivity to higher alcohols compared to the use of a solvent, iso-hexane (2-methyl-pentane, with critical temperature T.sub.c=498 K, critical pressure P.sub.c=30 bar), which is under sub-critical conditions at the applied process conditions, in Example 2. Comparative examples, not according to the present invention, lead to significantly lower selectivity and/or time-yield to C.sub.3+ alcohols.