CATALYST AND A PROCESS FOR CATALYTIC CONVERSION OF CARBON DIOXIDE-CONTAINING GAS AND HYDROGEN STREAMS TO HYDROCARBONS

Abstract

The invention relates to a catalyst suitable for use in the hydrogenation of carbon dioxide-containing gas, said catalyst comprising spinel phase of the formula [Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4]. Processes for preparing the catalyst and processes for the hydrogenation of carbon dioxide-containing gas in the presence of the catalyst are also disclosed.

Claims

1) A process for preparing a compound of Formula 1:
Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4Formula 1 wherein y is in the range from 0.25 to 0.75; comprising dissolving in an aqueous solution at least one ferric compound and at least one aluminum compound to form a metal-containing solution, adjusting the pH of said metal-containing solution by means of gradual addition of an alkaline agent, whereby co-precipitation of the metals in the form of their hydroxides occurs, wherein the pH is adjusted within the range from 7 to 8.5, separating the solid formed from the liquid phase, and subjecting same to drying and calcination to obtain hematite-free spinel of Formula 1.

2) A process according to claim 1, wherein the addition time of the alkaline agent is not less than 10 minutes.

3) A process according to claim 1, wherein the alkaline agent is an aqueous solution of ammonium hydroxide.

4) A process according to claim 3, wherein the concentration of the ammonium hydroxide solution is not more than 5% by weight.

5) A process according to claim 3, wherein the metal-containing solution and the ammonium hydroxide solution are held at room temperature during the addition.

Description

[0065] In the drawings:

[0066] The patent or application file contains at least one drawing/photograph executed in color. Copies of this patent with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0067] FIG. 1 shows the multicomponent elements distribution maps of K/FeAlO-spinel catalyst obtained by HRTEM/EELS: (1)after hydrogen reduction and stabilization in CO.sub.2 hydrogenation at 300 C. for 120 h; (2)after carburization and stabilization in CO.sub.2 hydrogenation at 300 C. for 120 h.

[0068] FIG. 2 shows XRD patterns of K/FeAlO-spinel catalyst: (1)fresh; (2)after activation by carburization; (3) after stabilization in CO.sub.2 hydrogenation at 300 C. for 120 h.

[0069] FIG. 3 demonstrates the effect of the content of Fe.sub.2O.sub.3 (Hematite) phase in the mixed Fe.sub.2O.sub.3FeAlO-spinel catalyst on the catalysts performance in CO.sub.2 hydrogenation. Testing conditions: T=300 C., P.sub.total=10 atm, H.sub.2/CO.sub.2=4.

[0070] FIG. 4 illustrates a scheme of an apparatus based on a cascade reactors system useful for CO.sub.2 hydrogenation. (1), (2) and (3) serially-positioned reactors; (4) discharge line; (5) cooler; (6) gas-liquid separator; (7) liquid-liquid separator; (8) organic collector; (9) aqueous phases collector; (10) feed line into the consecutive reactor; (11), (12) and (13) carbon dioxide, hydrogen and carbon monoxide feed lines, respectively; (14) flow controllers; (15), (16) gas feed lines.

[0071] FIG. 5 is a bar diagram illustrating the contents of paraffins, olefins, aromatics and oxygenates in the hydrocarbon oil obtained after one, two and three reactors in series.

EXAMPLES

Methods

[0072] X-Ray Diffraction (XRD)

[0073] The X-ray diffraction (XRD) patterns were obtained with a Phillips 1050/70 powder diffractometer fitted with a graphite monochromator, at 40 kV and 28 mA. Software developed by Crystal Logic was used. The data were collected in a range of 28 values between 5 and 80 with a step size of 0.05. Phase identification was performed by using BEDE ZDS computer search/match program coupled with the ICDD (International Center for Diffraction Data) Powder Diffraction File database (2006). The average crystal size of Fe.sub.3O.sub.4, Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 spinel, Fe.sub.2O.sub.3, Fe.sub.5C.sub.2 and Fe.sub.7C.sub.3 phases was determined from the Scherrer equation h=K/[(B.sup.2.sup.2).sup.0.5 cos(2/2)], where K=1.000 is the shape factor, =0.154 nm, is the instrumental broadening correction, and B is the reflection broadening at corresponding 2. The average crystal size was obtained by averaging of the data calculated for reflections (110), (200); (220), (311); (220), (311), (440); (020), (112); (102), (211) and (110), (200) of the XRD patterns corresponding to the Hematite Fe.sub.2O.sub.3 phase (ICDD Card 86-550), Magnetite Fe.sub.3O.sub.4 (ICDD Card 19-629), CuAlFeO spinels (ICDD Cards 34-192, 77-10), Hagg carbide Fe.sub.5C.sub.2 (ICDD Card 36-1248), carbide Fe.sub.7C.sub.3(ICDD Card 17-333) and metallic -Fe (ICDD Card 6-696) phases, respectively. The relative content of Fe-oxides, carbide phases and amorphous carbon phase represented in X-ray diffractograms by a wide reflection centered at 2=22 was obtained by Rietveld refinement of the XRD profile by using the DBWS-9807 program.

[0074] The composition of spinel phases nanoparticles in prepared catalytic materials was derived from XRD databy fitting the measured parameters of the unit cell of cubic Fe.sub.3O.sub.4-phase to the contents of Cu.sup.2+ and Al.sup.3+ ions at tetrahedral and octahedral positions, respectively, in the cubic framework of spinel phase with space group Fd3m. The parameters of unit cells of spinel phases were calculated based on the positions of reflections detected in X-ray diffractograms around 2=30 (220), 35.5 (311) and 63 (440).

Surface Area and Pore Volume Measurements

[0075] Surface area and pore volume were derived from N.sub.2 adsorption-desorption isotherms using conventional BET and BJH methods (Barrett-Joyner-Halenda method, Journal of American Chemical Society, 73, 373, 1951). The samples were degassed under vacuum at 250-70 C., depending on their thermal stability. Isotherms were measured at liquid nitrogen temperature with a NOVA-2000 Quantachrome, Version 7.02 instrument.

Energy Dispersive X-Ray Spectroscopy (EDAX)

[0076] The total elemental composition of catalysts was measured by EDAX method using Quanta-200, SEM-EDAX, FEI Co. instrument. The contents of Cu.sup.2+ and Al.sup.3+ ions in spinel nanoparticles were confirmed by the data of local EDAX method recorded with the electronic spot diameter of 5 nm with the field emission analytical transmission electron microscope (JEOL JEM-2100F) operated at accelerating voltage of 200 kV. The nanoparticles of spinel phases were identified by recording the multicomponent distribution maps for nanoparticles observed at HRTEM images.

High Resolution TEM/Electron Energy Loss Spectroscopy (HRTEM/EELS)

[0077] The transmission electron microscope (JEOL JEM-2100F) used for materials analysis was equipped with a Gatan imaging filter (GIF Quantum)/EELS system. Regular and energy-filtered images were taken from the same samples point for Fe, O and C elements at L-edge 708 eV; K-edge 532 eV and K-edge 284 eV, respectively. The obtained elemental distributions maps were further combined in one RGB image marking Fe by red, C by green and O by blue colors. This yielded multicomponent elements distribution maps for nanoparticles observed in regular HRTEM images. Gatan Digital Micrograph software was used for EFTEM imaging, recording and processing of EELS data. The samples for HRTEM were prepared by depositing a drop of ethanol suspension of the solid catalyst on a silica-coated copper grid that formed a contrast oxide background for carbon-rich particles.

Example 1 (Comparative)

Preparation of a Catalyst Consisting of Hematite Phase [Fe.SUB.2.O.SUB.3.] and Spinel Phase of the Formula [(Cu.SUP.2+..SUB.x.Fe.SUP.2+..SUB.1-x.)(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (x=0.54, y=0.65)]

[0078] The catalyst was prepared by co-precipitation from the aqueous solution of Fe, Cu and Al nitrates by addition of aqueous ammonium hydroxide solution. 21.0 gram of Al(NO.sub.3).sub.3.9H.sub.2O, 72.3 gram of Fe(NO.sub.3).sub.3.9H.sub.2O and 6.8 gram of Cu(NO.sub.3).sub.2.3H.sub.2O salts were dissolved in 20, 20 and 4 cm.sup.3 of distilled water, respectively. All three solutions were then mixed together, and 500 cm.sup.3 of 3% NH.sub.4OH solution were gradually added to this mixed salts solution at room temperature under stirring during a period of 10 min. The pH of solution after the addition of NH.sub.4OH was 6.8. A solid precipitated from the solution. The solid was separated by filtration and washed on the filter with 500 cm.sup.3 of distilled water. Then the solid was dried in air at 110 C. for period of h. The obtained material was impregnated by incipient wetness with aqueous solution containing 1.04 gram K.sub.2CO.sub.3. The impregnated material was dried in air at 110 C. for period of h and calcined in air at 450 C. for period of 6 h (temperature increasing rate 5 C./min). The material has the following weight ratio of metal components (EDAX): Fe:Al:K:Cu=100:15:6:5, surface area 100 m.sup.2/g, pore volume 0.17 cm.sup.3/g and average pore diameter 4.3 nm. The material contained two phases (XRD): 30 wt % of hematite Fe.sub.2O.sub.3 and 70 wt % of phase with spinel structure which composition reflects partial isomorphous substitution of Fe.sup.2+ ions with Cu.sup.2+, and Fe.sup.3+ ions with Al.sup.3+ ions, such that the spinel phase of the catalyst has the formula:

[(Cu.sup.2+.sub.xFe.sup.2+.sub.1-x)(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4] where x=0.54 and y=0.65.

Example 2 (Comparative)

Preparation of a Catalyst Consisting of Spinel Phase Only [(Cu.SUP.2+..SUB.x.Fe.SUP.2+..SUB.1-x.)(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (x=0.72, y=0.71)]

[0079] The catalyst was prepared according to procedure described in Example 1. However, in the present example the adjustment of pH value to 6.8 was achieved by adding 200 cm.sup.3 of aqueous NH.sub.4OH solution with concentration of ammonium hydroxide of 10%. The fast basification caused the inclusion of more Cu and Fe ions in (Cu.sup.2+.sub.xFe.sup.2+.sub.1-x)(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 spinel phase with x=0.72 and y=0.71. Correspondingly, no Fe.sub.2O.sub.3 hematite phase was formed after calcination at 450 C. The material had the following weight ratio of metal components (EDAX): Fe:Al:K:Cu=100:15:5:6, surface area 138 m.sup.2/gram, pore volume 0.20 cm.sup.3/gram and average pore diameter 4.3 nm.

Example 3 (Comparative)

Preparation of a Catalyst Consisting of Hematite Phase [Fe.SUB.2.O.SUB.3.] and Spinel Phase of the Formula [Fe.SUP.2+.(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.]; (y=0.40)]

[0080] The catalyst was prepared according to the procedure described in Example 1 but without any addition of Cu(NO.sub.3).sub.2 salt to the mixed solution of metal nitrates. The material has following weight ratio of metal components (EDAX): Fe:Al:K=100:15:6, surface area 107 m.sup.2/gram, pore volume 0.20 cm.sup.3/gram and average pore diameter 3.4 nm. The material contained two phases (XRD): 41 wt % of hematite Fe.sub.2O.sub.3 and 59 wt % of phase with spinel structure which composition reflects partial isomorphous substitution of Fe.sup.3+ ions with Al.sup.3+ ions, such that the spinel phase of the catalyst is represented by the following formula:

[Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 where y=0.40.

Example 4

Preparation of a Catalyst Consisting of Hematite Phase [Fe.SUB.2.O.SUB.3.] and Spinel Phase of the Formula [Fe.SUP.2+.(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.] (y=0.64)]

[0081] The catalyst was prepared according to the procedure described in Example 1, but without any addition of Cu(NO.sub.3).sub.2.3H.sub.2O salt to the mixed solution of metal nitrates. In this example 94 gram of Fe(NO.sub.3).sub.3.9H.sub.2O salt was used for preparation of iron salt solution in 50 cm.sup.3 water and for adjustment of the pH value to 6.8, 535 cm.sup.3 of 3% NH.sub.4OH aqueous solution were added to the metal salt solution. The resultant material has the following weight ratio of metal components (EDAX): Fe:Al:K=100:12:5, surface area 113 m.sup.2/gram, pore volume 0.21 cm.sup.3/gram and average pore diameter 4.9 nm. The material contained two phases (XRD): 45 wt % of hematite Fe.sub.2O.sub.3 and 55 wt % of phase with spinel structure whose composition reflects partial isomorphous substitution of Fe.sup.3+ ions with Al.sup.3+ ions, such that the spinel phase of the catalyst is represented by the formula:

[Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 where y=0.64.

Example 5 (Comparative)

Preparation of a Catalyst Consisting of Hematite Phase [Fe.SUB.2.O.SUB.3.] and Spinel Phase of the Formula [Fe.SUP.2+.(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.] (y=0.70)]

[0082] The catalyst was prepared according to the procedure described in Example 1 but without the addition of Cu(NO.sub.3).sub.2.3H.sub.2O salt to the mixed solution of metal nitrates. In this example 115.7 gram of Fe(NO.sub.3).sub.3.9H.sub.2O salt was used for preparation of iron salt solution in 62 cm.sup.3 of water and for the adjustment of the pH value to 6.8 was added 570 cm.sup.3 of 3% NH.sub.4OH aqueous solution. The material obtained has the following weight ratio of metal components (EDAX): Fe:Al:K=100:9:4, surface area 93 m.sup.2/gram, pore volume 0.21 cm.sup.3/gram and average pore diameter 6.5 nm. The material contained two phases (XRD): 86 wt % of hematite Fe.sub.2O.sub.3 and 14 wt % of phase with spinel structure whose composition reflects isomorphous substitution of Fe.sup.3+ ions with Al.sup.3+ ions, such that the spinel phase of the catalyst is represented by the formula [Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4] where y=0.70.

Example 6 (Comparative)

Preparation of a Catalyst Consisting of Iron Oxide Phases [Fe.SUB.2.O.SUB.3.; Fe.SUB.3.O.SUB.4.]

[0083] The procedure is according to U.S. Pat. No. 5,140,049.

[0084] Iron Oxide catalyst was obtained by combustion synthesis using glycolic acid as organic complexant. 12.6 gram of Glycolic acid were dissolved in 10% aqueous ammonia up to pH 6.5 and slowly added to a solution containing 67 gram of Fe(NO.sub.3).sub.3.9H.sub.2O dissolved in 50 cm.sup.3 of water. Then the water, ammonia and part of NO.sub.3.sup. ions converted to NO/NO.sub.2 were removed from the mixed solution in rotavapor increasing the temperature from 40 to 80 C. up to complete drying of the material. The dried precipitate was calcined in air at 350 C. for 1 h (heating rate 5 C. min.sup.1). The formed iron oxide was impregnated by incipient wetness method with aqueous K.sub.2CO.sub.3 solution, followed by drying in air at 110 C. overnight. The material consisted on 35 wt % Hematite Fe.sub.2O.sub.3 and 65 wt % Magnetite Fe.sub.3O.sub.4. It had surface area of 110 m.sup.2/gram, pore volume 0.31 cm.sup.3/gram and average pore diameter 4.3 nm.

Example 7 (of the Invention)

Preparation of a Catalyst Consisting of Copper-Free Spinel Phase Only [Fe (Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (y=0.47)]

[0085] The catalyst was prepared by co-precipitation from the aqueous solution of Fe and Al nitrates by gradual addition of aqueous ammonium hydroxide solution. 27.0 gram of Al(NO.sub.3).sub.3.9H.sub.2O and 57.9 gram of Fe(NO.sub.3).sub.3.9H.sub.2O were dissolved in 60 cm.sup.3 of distilled water each. The solutions were then mixed together and the pH value was adjusted to 8.0 by gradually adding 250 cm.sup.3 of aqueous NH.sub.4OH solution with concentration of ammonium hydroxide of 5 wt %. The addition time was 15 minutes. The precipitate was recovered and impregnated with K.sub.2CO.sub.3 solution as described in Example 1. In the present example the atomic ratio of Fe:Al in the precipitating solution was 2:1. Correspondingly, no Fe.sub.2O.sub.3 hematite phase was formed after calcination at 450 C. The material had the following weight ratio of metal components (EDAX): Fe:Al:K=100:24:6, surface area 128 m.sup.2/gram, pore volume 0.53 cm.sup.3/gram and average pore diameter 3.5 nm.

Example 8 (of the Invention)

Preparation of a Catalyst Consisting of Copper-Free Spinel Phase Only [Fe (Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (y=0.31)]

[0086] The catalyst was prepared by co-precipitation from the aqueous solution of Fe and Al nitrates by addition of aqueous ammonium hydroxide solution as described in Example 7. After mixing the aqueous solutions of Fe- and Al-salts the pH value was adjusted to 8.5 by gradually adding 265 cm.sup.3 of an aqueous NH.sub.4OH solution (with concentration of 5 wt %). The addition time was 15 minutes. The precipitate was recovered and impregnated with K.sub.2CO.sub.3 solution as described in Example 1. The material consisted of only oneAl-substituted Fe.sub.3O.sub.4 spinel phase of formula Fe(Fe.sup.3+.sub.0.31Al.sup.3+.sub.0.69).sub.2O.sub.4 and had following weight ratio of metal components (EDAX): Fe:Al:K=100:42:6, surface area 118 m.sup.2/gram, pore volume 0.43 cm.sup.3/gram and average pore diameter 3.0 nm.

Example 9 (of the Invention)

Preparation of a Catalyst Consisting of Copper-Free Spinel Phase Only [Fe (Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (y=0.71)]

[0087] The catalyst was prepared by co-precipitation from the aqueous solution of Fe and Al nitrates by addition of aqueous ammonium hydroxide solution as described in Example 7. After mixing the aqueous solutions of Fe- and Al-salts the pH value was adjusted to 7.2 by gradually adding 100 cm.sup.3 of aqueous NH.sub.4OH solution with concentration of ammonium hydroxide of 5 wt %. The addition time was 15 minutes and the precipitate was recovered and impregnated with K.sub.2CO.sub.3 solution as described in Example 1. The material consisted of only oneAl-substituted Fe.sub.3O.sub.4 spinel phase of formula Fe(Fe.sup.3+.sub.0.71Al.sup.3+.sub.0.29).sub.2O.sub.4 and had following weight ratio of metal components (EDAX): Fe:Al:K=100:12:6, surface area 103 m.sup.2/gram, pore volume 0.38 cm.sup.3/gram and average pore diameter 3.7 nm.

Example 10 (Comparative)

Preparation of a Catalyst Consisting on Iron, Copper and Potassium Deposited on Al.SUB.2.O.SUB.3 .Support

[0088] (According to WO 97/05088, WO 01/34538 A1, U.S. Pat. No. 4,555,526). To 36 gram of Fe(NO.sub.3).sub.3.9H.sub.2O, 1.25 gram of Cu(NO.sub.3).sub.2.3H.sub.2O and 3 gram of K.sub.2CO3 dissolved in 100 cm.sup.3 of distilled water was added 20 gram of a powder of -Al.sub.2O.sub.3 with surface area of 180 m.sup.2/gram. The mixture was vigorously stirred and heated at 80 C. to evaporate water. After evaporation of water, the solid reaction mixture was dried at 120 C. in air for 24 hours and calcined at 450 C. for 6 hours. The obtained catalyst had following weight ratio of metal components (EDAX): Fe:Cu:Al:K=100:6:21:0.34, surface area 76 m.sup.2/gram, pore volume 0.16 cm.sup.3/gram and average pore diameter 8.2 nm.

[0089] The compositions of the catalysts of Examples 1 to 10 are tabulated in Table A.

TABLE-US-00001 TABLE A Hematite phase Spinel phase catalyst Fe.sub.2O.sub.3 (Cu.sup.2+.sub.xFe.sup.2+.sub.1x) (Fe.sup.3+.sub.yAl.sup.3+.sub.1y).sub.2O.sub.4 1 30% wt % 70% wt % comparative x = 0.54, y = 0.65 2 0% 100 wt % comparative x = 0.72, y = 0.71 3 41% (wt %) 59% (wt %) comparative x = 0.00, y = 0.40 4 45% (wt %) 55% (wt %) comparative x = 0.00, y = 0.64 5 86% (wt %) 14% (wt %) comparative x = 0.00, y = 0.70 6 20% (wt %) comparative Fe.sub.3O.sub.4 80% (wt %) 7 0% 100 wt % of the invention x = 0.0; y = 0.47 8 0% 100 wt % of the invention x = 0.0; y = 0.31 9 0% 100 wt % of the invention x = 0.0; y = 0.71 10 FeCuK/Al2O3 comparative

[0090] In the next set of examples (Examples 11-22), the catalysts of Examples 1-10 were tested for their activity and selectivity in CO.sub.2 hydrogenation reaction to form fuel compositions. Catalysts testing included catalyst activation, reaction and products analysis.

[0091] Catalysts activation was done by means of two methods: reduction in hydrogen at 100 cm.sup.3/min*gram.sub.cat, temperature 450 C., atmospheric pressure for 24 h; and carburization in a mixture of carbon monoxide and hydrogen in helium at flows 30:30:140 cm.sup.3/min*gram.sub.cat respectively, at temperature 300 C., atmospheric pressure for 3 h.

[0092] CO.sub.2 hydrogenation reaction was conducted by passing a mixture of H.sub.2 and CO.sub.2 flows at ratio 4:1 through the 3 gram of catalyst mixed with 1.8 gram of inert silica packed in a tubular reactor (11 mm ID and 210 mm long, 45 mm catalytic phase) and heated up to 300 C. or 320 C. at the total pressure of 10 atm. The reaction products were cooled down to +4 C. and separated in cooled (+4 C.) container. Gas products were analyzed in online Agilent 7890A Series Gas Chromatograph equipped with 7 columns and 5 automatic valves using helium as a carrier gas. Liquid products were separated into aqueous and organic phases. Aqueous phase was analyzed for Total Organic Carbon in Shimadzu TOC-V.sub.CPN Analyzer. The liquid organic phase composition was analyzed by Agilent 190915-433 Gas Chromatograph combined with Mass Spectrometer in the range M/Z=33-500, equipped with 5973 mass selective detector, HP-5MS column (30 m, 250 m, i.d. 0.25 m) and helium as a carrier gas. The distillation patterns of hydrocarbon oil were estimated by simulated distillation method based on the maximal boiling points of components in 10 vol % oil fractions. The oil productivity was calculated based on the weighted amounts of organic liquid (W.sub.oil) collected over a specific period of time on stream: OP=W.sub.oil/W.sub.cat/RT gram/gram catalyst/h, where W.sub.cat is weight of catalyst (gram) loaded to reactor, RTtime period on stream (hours). The selectivity to CO, CH.sub.4, C.sub.2-C.sub.5 and C.sub.6+ hydrocarbons was calculated on the carbon basis as S.sub.i=[C.sub.i/(C.sub.CO2*X.sub.CO2)]*100%, where C.sub.i amount of carbon (gram) contained in product (i) produced at period of time, C.sub.CO2amount of carbon (gram) contained in CO.sub.2 passed the reactor at the same period of time, X.sub.CO2CO.sub.2 conversion. In the tables below, the following abbreviations are used: Con for conversion, Sel for selectivity and Pro for productivity.

Example 11

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0093] The Catalyst of Example 1 was packed in a fixed bed reactor and activated by H.sub.2 reduction as described above. The effect of WHSV on the reaction products was determined. The results are shown in Table 1. Increasing of the space time by decreasing of WHSV of CO.sub.2 did not increase the CO.sub.2 conversion beyond 60%.

TABLE-US-00002 TABLE 1 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 2 36 9 13 44 11.3 25 6.4 1 46 9 9 42 6.3 29 4.3 0.5 52 9 7 46 4.3 30 2.8 0.2 59 9 5 44 1.9 35 1.5 0.1 60 9 4 35 0.7 29 0.6

Example 12

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0094] The catalyst of Example 1 was packed in a fixed bed reactor and activated by carburization as described above. The effect of WHSV upon the reaction products was determined. The results are shown in Table 2. Comparison of the results presented in Tables 1 and 2 indicates a significantly higher activity of the catalyst after carburization compared with its activation by hydrogen reduction. Higher CO.sub.2 conversions and oil productivities were measured at different WHSV with carburized catalyst.

TABLE-US-00003 TABLE 2 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 6 40 10 12 38 32.2 29 24.6 3 46 11 7 41 20.1 26 12.5 1 53 8 5 15 10.9 19 3.5

[0095] Reaction conditions: Temperature 300 C., Total pressure 10 atm, H.sub.2/CO.sub.2=4 mol/mol.

Example 13

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0096] Catalyst prepared as described in Example 3 was packed in a fixed bed reactor and activated by carburization as described above. The effects of WHSV on the reaction products were determined. The results are shown in Table 3.

TABLE-US-00004 TABLE 3 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 52 9 10 45 8.3 25 4.7 6 41 10 20 44 36.3 15 12.3

[0097] Reaction conditions: Temperature 300 C., Total pressure 10 atm, H.sub.2/CO.sub.2=4.

Example 14

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0098] Catalyst prepared as described in Example 4 was packed in a fixed bed reactor and activated by carburization as described above. Effects of WHSV upon the reaction products were determined. The results are shown in Table 4.

TABLE-US-00005 TABLE 4 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 53 9 6 46 8.5 24 4.5 6 33 6 31 41 27.4 15 9.8

[0099] Reaction conditions: T=300 C., P=10 atm, H.sub.2/CO.sub.2=4.

Example 15

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0100] Catalyst prepared as described in Example 5 was packed in a fixed bed reactor and activated by carburization as described above. The effects of WHSV on the reaction products were determined. The results are shown in Table 5.

TABLE-US-00006 TABLE 5 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 37 8 14 50 6.6 20 3.5 6 20 7 83 1 0.2 3 1.0

[0101] Reaction conditions: T=300 C., P=10 atm, H.sub.2/CO.sub.2=4.

Example 16

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor in the Presence of a Catalyst Consisting of Spinel Phase Only (Cu-Free)

[0102] Catalyst prepared as described in Example 7 was packed in a fixed bed reactor and activated by carburization as described above. The effect of WHSV upon the reaction products was determined. The results are shown in Table 6.

TABLE-US-00007 TABLE 6 CO.sub.2 CO.sub.2 Methane CO C.sub.2-C.sub.5 C.sub.6+ oil WHSV Con., Sel. Sel. Sel. Pro. Sel. Pro. h.sup.1 % % % % (g/g.sub.cat .Math. h) .Math. 10.sup.2 % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 52 12 6 39 7.9 29 5.8 6 45 12 13 27 26 40 38.5

[0103] Reaction conditions: T=300 C., Total pressure 10 atm, H.sub.2/CO.sub.2=4.

[0104] The selectivities to C.sub.6+ hydrocarbons and oil productivity obtained with this catalyst of the present invention are significantly higher compared to that measured with carburized K/FeO.sub.x or biphasic K/CuFeAlOFe.sub.2O.sub.3, K/FeAlOFe.sub.2O.sub.3 catalysts.

Example 17

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor in the Presence of a Catalyst Consisting of Spinel Phase Only (Containing Cu)

[0105] Catalyst prepared as described in Example 2 was packed in a fixed bed reactor and activated by H.sub.2. The effect of WHSV upon the reaction products was determined. The results are shown in Table 7.

TABLE-US-00008 TABLE 7 CO.sub.2 C.sub.2-C.sub.5 C.sub.6+ oil WHSV CO.sub.2 Methane CO Pro. Pro. h.sup.1 Con., % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 35 9 28 39 4.9 16 2.0 6 23 8 39 46 22.6 6 2.9

[0106] Reaction conditions: T=300 C., Total pressure 10 atm, H.sub.2/CO.sub.2=4.

Example 18

Testing in One Fixed Bed Reactor of a Catalyst Consisting of Iron Oxide Phases [Fe.SUB.2.O.SUB.3.; Fe.SUB.3.O.SUB.4.] and not Containing Spinel Phase

[0107] The catalyst prepared according to Example 6 was packed in the tubular reactor and activated by carburization as described above. The testing results are shown in Table 8.

TABLE-US-00009 TABLE 8 C.sub.2-C.sub.5 C.sub.6+ oil Pro. Pro. CO.sub.2 Methane CO Sel. (g/g.sub.cat .Math. h) .Math. Sel. (g/g.sub.cat .Math. h) .Math. Con., % Sel. % Sel. % % 10.sup.2 % 10.sup.2 39 8 16 46 5.9 21 2.7

[0108] Reaction conditions: 300 C., 10 atm, H.sub.2/CO.sub.2=4, WHSV=1.0 h.sup.1

Example 19

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0109] The catalyst prepared according to Example 9 was packed in the tubular reactor and activated by hydrogen reduction as described above. The testing results are shown in Table 9.

TABLE-US-00010 TABLE 9 C.sub.2-C.sub.5 C.sub.6+ oil Pro. Pro. CO.sub.2 Methane CO Sel. (g/g.sub.cat .Math. h) .Math. Sel. (g/g.sub.cat .Math. h) .Math. Con., % Sel. % Sel. % % 10.sup.2 % 10.sup.2 27 10 28 48 4.6 11 1.1

[0110] Reaction conditions: Temperature 300 C., total pressure 10 atm, H.sub.2/CO.sub.2=4, WHSV=1 h.sup.1.

Example 20

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0111] The catalyst prepared according to Example 8 was packed in the tubular reactor and activated by carburization as described above. The testing results are shown in Table 10.

TABLE-US-00011 TABLE 10 CO.sub.2 C.sub.2-C.sub.5 C.sub.6+ oil WHSV CO.sub.2 Methane CO Pro. Pro. h.sup.1 Con., % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 52 13 6 41 7.6 27 5.0

[0112] Reaction conditions: Temperature 300 C., total pressure 10 atm, H.sub.2/CO.sub.2=4, WHSV=1 h.sup.1.

Example 21

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0113] The catalyst prepared according to Example 9 was packed in the tubular reactor and activated by carburization as described above. The testing results are shown in Table 11.

TABLE-US-00012 TABLE 11 CO.sub.2 C.sub.2-C.sub.5 C.sub.6+ oil WHSV CO.sub.2 Methane CO Pro. Pro. h.sup.1 Con., % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 53 13 7 40 7.6 28 5.3

[0114] Reaction conditions: Temperature 300 C., total pressure 10 atm, H.sub.2/CO.sub.2=4, WHSV=1 h.sup.1.

Example 22

Carbon Dioxide Hydrogenation in One Fixed Bed Reactor

[0115] The catalyst prepared according to Example 10 was packed in the tubular reactor and activated by hydrogen reduction as described above. The testing results are shown in Table 12.

TABLE-US-00013 TABLE 12 C.sub.2-C.sub.5 C.sub.6+ oil Pro. Pro. CO.sub.2 Methane CO Sel. (g/g.sub.cat .Math. h) .Math. Sel. (g/g.sub.cat .Math. h) .Math. Con., % Sel. % Sel. % % 10.sup.2 % 10.sup.2 38 8 15 58 7.9 8.6 1.2

[0116] Reaction conditions: Temperature 300 C., total pressure 10 atm, H.sub.2/CO.sub.2=4, WHSV=1 h.sup.1.

[0117] CO.sub.2 conversion levels achieved by the catalysts of Examples 1-10, when operating under the following set of experimental conditions: Temperature 300 C., total pressure 10 atm, H.sub.2/CO.sub.2=4, WHSV.sub.CO2=1 h.sup.1, as reported in Examples 11-22, are tabulated in Table B.

TABLE-US-00014 TABLE B catalyst CO2 conversion % 1 53 2 35 3 52 4 53 5 37 6 39 7 52 8 52 9 53 10 40

[0118] In the next set of examples (Examples 23-27), some of the catalysts demonstrating CO.sub.2 conversion of slightly more than 50% according to the data tabulated in Table B (i.e., the catalysts of Examples 1, 3, 4 and 7) were tested in an experimental set-up consisting of three reactors positioned in series, with water removal taking place between each pair of consecutive reactors, i.e., between the first and second reactors, and between the second and third reactors.

Example 23

Carbon Dioxide Hydrogenation in Three Reactors in Series

[0119] 6 gram of the catalyst prepared as described in Example 1 was packed in three fixed bed reactors in series. 2 gram of catalyst was packed in each reactor and activated by carburization as described above. The testing system consisted of 3 consecutive SS fixed bed reactors with pressure, temperature and flow controls (shown in FIG. 4). After each reactor the heavy organic products (oil) and water were condensed in a cooling system and collected in the tank. After separation of liquid products, the gases containing non-reacted CO.sub.2, H.sub.2 and light Hydrocarbons, C.sub.1-C.sub.5 proceeded to flow to the next reactor. After each reactor the gas and liquid products were analyzed as described above. All the three reactors were kept at the same temperature and total pressure of 10 atm.

[0120] The catalyst performance as a function of temperature, H.sub.2:CO.sub.2 molar ratio and the number of reactors (N) in the testing system is listed in Table 13.

TABLE-US-00015 TABLE 13 CO.sub.2 C.sub.2-C.sub.5 C.sub.6+ oil T WHSV CO.sub.2 CH.sub.4 CO Pro. Pro. N C. H.sub.2:CO.sub.2 h.sup.1 Con. % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 300 4:1 6 40 12 11 35 26.6 31 23.2 2 300 4:1 3 62 12 5 40 23.4 33 19.3 3 300 4:1 2 77 12 2 42 34.2 34 17.6 3 320 3:1 2 72 9 3 32 37.8 38 18.1 3 320 4:1 2 90 12 1 44 34.0 34 19.0 3 320 6:1 2 93 18 1 47 26.7 27 16.2

Example 24

Carbon Dioxide Hydrogenation in Three Reactors in Series

[0121] 6 gram of catalyst prepared as described in Example 3 was packed in three fixed bed reactors in series as set out in Example 23. The aqueous and liquid hydrocarbons phases were separated from light gases between first and second and between second and third reactors as shown in FIG. 4. The catalyst in all three reactors was activated by carburization as described above and tested as in Example 23. The effects of temperature and total pressure upon the reaction products were determined. The results are shown in Table 14. The oil hydrocarbon composition was similar to that obtained for oil collected in Example 23.

TABLE-US-00016 TABLE 14 CO.sub.2, C.sub.2-C.sub.5 C.sub.6+ oil T, P, WHSV CO.sub.2 CH.sub.4 CO Pro. Pro. N C. atm h.sup.1 Con. % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 300 10 6 41 10 20 44 36.3 15 12.3 3 300 10 2 79 10 4 42 21.8 33 17 3 320 10 2 84 11 2 38 21.2 37 20.7 3 320 15 2 86 12 2 30 16.6 43 24.0 3 320 5 2 62 9 30 40 16.7 16 6.9

[0122] Reaction conditions: H.sub.2/CO.sub.2=4.

Example 25

Carbon Dioxide Hydrogenation in Three Reactors in Series

[0123] 6 gram of catalyst prepared as described in Example 6 was packed in three fixed bed reactors in series as set out in Example 23. The catalyst was activated by carburization as described above and tested as in Example 23. The effect of WHSV upon the reaction products was determined. The results are shown in Table 15. The oil hydrocarbon composition was similar to that obtained for oil collected in Example 23.

TABLE-US-00017 TABLE 15 CO.sub.2, C.sub.2-C.sub.5 C.sub.6+ oil WHSV CO.sub.2 CH.sub.4 CO Pro. Pro. N h.sup.1 Con. % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 3 1 70 10 10 34 7.8 28 6.5 3 2 57 8 20 39 14.0 26 10.6

[0124] Reaction conditions: T=300 C., H.sub.2/CO.sub.2=4, total pressure 10 atm.

Example 26

Carbon Dioxide Hydrogenation in Three Reactors in Series in the Presence of a Catalyst Consisting of Spinel Phase Only (Cu-Free Catalyst)

[0125] 6 gram of catalyst prepared as described in Example 7 was packed in three fixed bed reactors in series as set out in Example 23. The aqueous and liquid hydrocarbons phases were separated from light gases between first and second and between second and third reactors as shown in the scheme of FIG. 4. The catalyst in all three reactors was activated by carburization as described above and tested as in Example 23. The effects of WHSV.sub.CO2 upon the reaction products were determined. The results are shown in Table 16. The cascade reactors configuration with this catalyst of the present invention gives maximal C.sub.6+ hydrocarbons selectivity and oil productivity about 0.5 kg/kg.sub.cat h.

TABLE-US-00018 TABLE 16 CO.sub.2, C.sub.2-C.sub.5 C.sub.6+ oil T, P, WHSV CO.sub.2 CH.sub.4 CO Pro. Pro. N C. atm h.sup.1 Con. % Sel. % Sel. % Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 Sel. % (g/g.sub.cat .Math. h) .Math. 10.sup.2 1 320 10 2 54 10 11 36 12.3 32 10.9 3 320 10 2 89 13 4 30 18.8 47 29.6 3 320 10 6 81 15 7 35 44.9 38 59.2

[0126] Reaction conditions: T=320 C., Total pressure 10 atm, H.sub.2/CO.sub.2=4.

Example 27

Carbon Dioxide/Carbon Monoxide Hydrogenation in Three Reactors in Series

[0127] 6 gram of catalyst prepared as described in Example 7 was packed in three fixed bed reactors in series with pressure, temperature and flow controls as set out in Example 23. 2 gram of the catalyst was packed in each reactor and activated by carburization as described above. The catalyst was tested in hydrogenation reaction of the mixture of CO.sub.2 and CO by feeding a mixture of H.sub.2, CO.sub.2 and CO flows at molar ratio 5:1:1, respectively. After each reactor the heavy organic products (oil) and water were condensed in a cooling system and collected in the tank. After separation of liquid products, the gases containing non-reacted CO.sub.2, CO and H.sub.2 and light hydrocarbons flowed to the next reactor. The gas products were analyzed as described above after the third reactor. The liquids were collected from three reactors were mixed and analyzed as described above. All the three reactors were kept at the same temperature and total pressure. The oil productivity was calculated based on the weighted amounts of organic liquid (W.sub.oil) collected per hour: OP=W.sub.oil/W.sub.cat/h, where W.sub.cat is total weight of loaded catalyst. The selectivity to CH.sub.4, C.sub.2-C.sub.5 and C.sub.6+ hydrocarbons was calculated on the carbon basis as S.sub.i=[C.sub.i/(C.sub.CO2+CO*X.sub.Total)]*100%, where C.sub.i amount of carbon (gram) contained in product (i) produced at period of time, C.sub.CO2+COamount of carbon (gram) contained in both CO.sub.2 and CO that flowed through the reactor at the same period of time, X.sub.Totaltotal conversion of C calculated as C.sub.reacted/C.sub.in (weight fraction). The effect of pressure upon the reaction products was determined. The results are shown in Table 17.

TABLE-US-00019 TABLE 17 C.sub.2-C.sub.5 C.sub.6+ oil CO.sub.2 CO CO.sub.2 + CO Pro. Pro. WHSV WHSV WHSV CH.sub.4 Total (g/g.sub.cat .Math. h) .Math. (g/g.sub.cat .Math. h) .Math. h.sup.1 h.sup.1 h.sup.1 P atm CO.sub.2Con % COCon % Sel % Con % Sel % 10.sup.2 Sel % 10.sup.2 1.0 0.6 1.6 10 55 97 13.4 73.2 52.4 22.1 29 12.3 1.0 0.6 1.6 15 66 98 14.1 80.0 50 23.1 30 13.9

[0128] Reaction conditions: T=320 C., H.sub.2/CO.sub.2/CO=5:1:1.

Example 28

Carbon Dioxide Hydrogenation in Three Reactors in Series with Different Catalysts at CO.SUB.2 .Conversion of 75% Adjusted by Varying of WHSV.SUB.CO2

[0129] In the set of experiments described in this Example, the performance (activity and selectivity) of the catalysts tabulated in Table B was measured under identical conditions (the same feed composition, temperature, pressure and CO.sub.2 conversion). The latter variable is controlled by varying the space velocity. Using the three packed-bed-reactors-in-series system illustrated in FIG. 4, high CO.sub.2 conversion (75%) was reached to reflect the selectivity to hydrocarbons.

[0130] Thus, 6 gram of catalysts prepared as described in Examples 1, 3, 4, 6, 7, 8 and 9 were packed in separate experiments in three fixed bed reactors in series as set out in Example 23. The catalysts were activated by carburization as described above. The results set out in Table 18 were measured for every catalyst after 200 h of run at 300 C., P=10 atm, H.sub.2/CO.sub.2=4 and properly adjusted WHSV.sub.CO2 to produce total CO.sub.2 conversion of 75%.

TABLE-US-00020 TABLE 18 Products selectivity, wt % C2-C4 WHSV.sub.CO2 C2-C4 C2-C4 Oxygenates C5+ pro. Catalyst h.sup.1 CH.sub.4 CO Olefins paraffins in water C5+ g/g.sub.cat .Math. h .Math. 10.sup.2 1 2.0 12 2 29 8 7 41 20.3 3 1.5 10 3 30 10 9 38 15.2 4 1.5 11 4 29 9 8 37 14.8 6 1.0 10 9 29 8 8 35 8.2 7 6.0 16 3 28 8 7 38 54.8 8 5.0 14 3 29 9 7 38 50.8 9 4.0 15 4 28 8 8 37 40.6

[0131] The results shown in Table 18 demonstrate that the catalysts consisting of pure phase of Al-substituted Fe.sub.3O.sub.4 with spinel structure, i.e., the catalysts represented by Formula 1 Fe.sup.2+(Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4; (y=0.05-0.95, preferably y=0.25-0.75 and more preferably y=0.30-0.70), i.e., catalysts of Examples 7, 8 and 9, display higher catalytic activity in conversion of CO.sub.2 to hydrocarbons compared with the catalysts of Examples 1, 3, 4 and 6.

Example 29

Preparation of Extruded Catalyst Consisting of Spinel Phase Only [Fe(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4.; (x=0.00, y=0.47)]

[0132] Fe (Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 from Example 7 was formed as extrudates with cylindrical shape using Al.sub.2O.sub.3 as a binder. 11.73 gram of Fe (Fe.sup.3+.sub.yAl.sup.3+.sub.1-y).sub.2O.sub.4 prepared in Example 7 was mixed with 4.89 gram of AlOOH powder (Disperal P2, Sasol Ltd., Germany) and water was added to get a slurry. The slurry was kneeded in a mortar and extruded using a matrix with 1.2 mm cylindrical shape opening. The extrudates were dried at room temperature for 24 h, then at 110 C. overnight and calcined at 450 C. for period of 2 h (temperature increasing rate 5 C./min). The so-formed material was impregnated by incipient wetness with aqueous solution containing 2.15 gram K.sub.2CO.sub.3. The impregnated material was dried in air at 110 C. for period of 24 h and calcined in air at 450 C. for period of 2 h (temperature increasing rate 5 C./min).

Example 30

Preparation of a Catalyst K/Fe.SUP.2+.(Fe.SUP.3+..SUB.y.Al.SUP.3+..SUB.1-y.).SUB.2.O.SUB.4 .(y=0.47) in the Form of Binder-Free Granules

[0133] The powder product of Example 7 was loaded into a round template with inner diameter of 4 cm. A load of 20 tons was applied twice on the sample. The so-formed binder-free pellet was crushed and a faction consisting of granules with size in the range from 1.4 to 1.7 mm was collected by sieving.

Example 31

Carbon Dioxide Hydrogenation in Three Reactors in Series

[0134] 15 gram of the catalyst of Example 30 in the form of pellets with sizes in the range of 1.4-1.7 mm were packed in three 16 mm ID and 300 mm long fixed bed reactors equipped with 2.3 mm ID thermowells and arranged in series as illustrated in FIG. 4. Each reactor contained 5 gram of catalyst diluted with 15 gram of silica. The total pressure at the inlet was 30 atm and pressure drop in the system of less than 0.5 atm. The feedstock consisted of H.sub.2 and CO.sub.2 at a molar ratio of 2.9 and WHSV of CO.sub.2 was 0.7. The temperature profile in each reactor is given in Table 19. The performance is set out in Table 20.

TABLE-US-00021 TABLE 19 Position in the First reactor Second reactor Third reactor reactor (cm) Temperature 0 326 324 323 1 334 325 325 2 338 325 325 3 336 326 323 4 330 325 322 5 327 324 321 6 325 323 320 7 324 322 319 8 322 320 317

TABLE-US-00022 TABLE 20 S.sub.C3-C4 S.sub.C2-C4 X.sub.CO2 X.sub.H2 S.sub.C5+ S.sub.C7+ S.sub.Methane S.sub.Ethylene S.sub.CO olefins paraffins S.sub.oxygenates 76.6 84.7 57.9 53.9 8.8 4.1 1.6 13.4 5.2 9.1

Example 32

Carbon Dioxide/Carbon Monoxide Hydrogenation in Three Reactors in Series

[0135] 3 grams of the catalyst of Example 7 in a powder form were packed in three 11 mm ID and 150 mm long fixed bed reactors equipped with 2.3 mm ID thermowells and arranged in series as illustrated in FIG. 4. Each reactor contained 1 gram of catalyst diluted with 3 gram of silica. The total inlet pressure was 20 atm and pressure drop in the system of less than 0.5 atm, the feedstock consisted of CO.sub.2, CO and H.sub.2 at a molar ratio of 1:1:4.8 and WHSV of CO.sub.2 and CO combined of 2 h.sup.1. The temperature profile in each reactor is given in Table 21. The performance is set out in Table 22.

TABLE-US-00023 TABLE 21 Position in the First reactor Second reactor Third reactor reactor (cm) Temperature 0 306 313 312 0.5 312 322 319 1.0 315 330 325 1.5 318 332 327 2.0 322 333 328 2.5 324 331 327 3.0 327 329 325 3.5 329 324 320

TABLE-US-00024 TABLE 22 S.sub.C3-C4 S.sub.C2-C4 X.sub.CO2 X.sub.CO X.sub.H2 S.sub.C5+ S.sub.C7+ S.sub.Methane S.sub.Ethylene S.sub.CO olefins paraffins S.sub.oxygenates 41.8 95.5 75.2 50.6 46.0 11.5 4.1 4.0 16.7 9.7 7.2

Example 33

Carbon Dioxide/Carbon Monoxide Hydrogenation in Three Reactors in Series

[0136] 3 grams of the catalyst of Example 7 in a powder form were packed in three 11 mm ID and 150 mm long fixed bed reactors equipped with 2.3 mm ID thermowells and arranged in series as illustrated in FIG. 4. Each reactor contained 1 gram of catalyst diluted with 3 gram of silica. The total inlet pressure was 20 atm and pressure drop in the system of less than 0.5 atm, the feedstock consisted of CO.sub.2, CO and H.sub.2 at a molar ratio of 1:0.7:4.1 and WHSV of CO.sub.2 and CO combined of 0.9 h.sup.1. The temperature profile in each reactor is given in Table 23. The performance is set out in Table 24.

TABLE-US-00025 TABLE 23 Position in the First reactor Second reactor Third reactor reactor (cm) Temperature 0 308 321 321 0.5 313 328 328 1.0 317 334 333 1.5 320 338 335 2.0 322 339 336 2.5 323 339 336 3.0 324 338 334 3.5 324 334 331

TABLE-US-00026 TABLE 24 S.sub.C3-C4 S.sub.C2-C4 X.sub.CO2 X.sub.CO X.sub.H2 S.sub.C5+ S.sub.C7+ S.sub.Methane S.sub.Ethylene S.sub.CO olefins paraffins S.sub.oxygenates 56.3 95.9 81.8 62.4 59.7 8.8 1.7 1.8 10.3 10.6 6.1