A COBALT-CONTAINING CATALYST COMPOSITION

Abstract

The present invention relates to catalysts, more particularly to a cobalt-containing catalyst composition. The present invention further relates to a process for preparing a cobalt-containing catalyst precursor, a process for preparing a cobalt-containing catalyst, and a hydrocarbon synthesis process wherein such a catalyst is used. According to a first aspect of the invention, there is provided a cobalt-containing catalyst composition comprising cobalt and/or a cobalt compound supported on and/or in a silica (SiO.sub.2) catalyst support wherein the average pore diameter of the catalyst support is more than 20 nm but less than 50 nm; the catalyst composition also including a titanium compound on and/or in the catalyst support, and a manganese compound on and/or in the catalyst support.

Claims

1.-15. (canceled)

16. A cobalt-containing catalyst composition comprising cobalt and/or a cobalt compound supported on and/or in a silica (SiO.sub.2) catalyst support wherein the average pore diameter of the catalyst support is more than 20 nm but less than 50 nm as determined by means of Barrett-Joyner-Halenda (BJH) nitrogen physisorption analysis; the catalyst composition also including a titanium compound on and/or in the catalyst support, and a manganese compound on and/or in the catalyst support.

17. The catalyst composition according to claim 16, wherein the silica catalyst support is an amorphous silica support.

18. The catalyst composition according to claim 16, wherein the silica catalyst support has an average pore diameter of more than 22 nm.

19. The catalyst composition according to claim 18, wherein the silica catalyst support has an average pore diameter of from 25 to 35 nm.

20. The catalyst composition according to claim 16, wherein the composition includes more than 1 wt % and not more than 10 wt % Ti, based on the weight of the silica (SiO.sub.2) catalyst support (excluding the weight of the Ti and Mn), the Ti being present in the form of one or more titanium compounds.

21. The catalyst composition according to claim 16, wherein the titanium compound is an organic titanium compound.

22. The catalyst composition according to claim 21, wherein the organic titanium compound is selected from the group consisting of titanium (IV) methoxide; titanium (IV) ethoxide; titanium (IV) propoxide; titanium (IV) isopropoxide; titanium (IV) diisopropoxide bis(acetylacetonate); titanium (IV) 2-ethylhexoxide; titanium (IV) hexoxide; titanium(IV) butoxide and titanium (IV) bis(ammonium lactato) dihydroxide.

23. The catalyst composition according to claim 16, wherein the composition includes more than 0.5 wt % and less than 10 wt % Mn, based on the weight of the silica (SiO.sub.2) catalyst support (excluding the weight of the Ti and Mn), the Mn being present in the form of one or more manganese compounds.

24. The catalyst composition according to claim 16, wherein the manganese compound is an organic manganese compound.

25. The catalyst composition according to claim 16, wherein the manganese compound is an inorganic manganese compound.

26. The catalyst composition according to claim 16, wherein the catalyst composition includes cobalt with a zero valency.

27. A process for preparing a cobalt-containing catalyst precursor, the process comprising introducing a cobalt compound onto and/or into a silica catalyst support wherein the average pore diameter of the catalyst support is more than 20 nm but less than 50 nm as determined by means of Barrett-Joyner-Halenda (BJH) nitrogen physisorption analysis; prior to and/or during and/or subsequent to introducing the cobalt compound onto and/or into the catalyst support, introducing a titanium compound onto and/or into the catalyst support; and prior to, and/or during, and/or subsequent to introducing the cobalt compound onto and/or into the catalyst support, introducing a manganese compound onto and/or into the catalyst support, thereby providing a cobalt-containing catalyst precursor.

28. A process for preparing a cobalt-containing catalyst, the process comprising preparing a cobalt-containing catalyst precursor according to the process of claim 27; and reducing the catalyst precursor, thereby activating the catalyst precursor.

29. A hydrocarbon synthesis process which comprises contacting a cobalt-containing catalyst composition of claim 26, with hydrogen and carbon monoxide at a temperature above 100° C. and at a pressure of at least 10 bar with the catalyst, to produce hydrocarbons and optionally, oxygenates of hydrocarbons.

30. The hydrocarbon synthesis process according to claim 29, wherein a hydroprocessing step is included for converting the hydrocarbons and optionally oxygenates thereof to liquid fuels and/or other chemicals.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0151] The invention will now be described in more detail, by way of example only, with reference to the accompanying figures in which:

[0152] FIG. 1: is a graph showing the FT rate over Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9;

[0153] FIG. 2: is a graph showing methane selectivity over Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9;

[0154] FIG. 3: is a graph depicting cumulative Al dissolution as a function of time for the Mn-modified, Ti-modified, MnTi-modified, unmodified alumina, Si—Al.sub.2O and MnSi-Al.sub.2O.sub.3 supports;

[0155] FIG. 4: is a graph showing the FT rate over Examples 33, 37, 38 RCR and 39 relative to Example 38 SR;

[0156] FIG. 5: is a graph showing the CH.sub.4 selectivity over Examples 33, 37, 38 RCR and 39 relative to Example 38 SR;

[0157] FIG. 6: is a graph showing C5+ productivity over Example 38 SR;

[0158] FIG. 7: is a graph showing the FT rate over Examples 40, 41, 42, 44, 46, 47, 48, 49 and 50 relative to Examples 38 SR; and

[0159] FIG. 8: is a graph showing the CH.sub.4 selectivity over Examples 40, 41, 42, 44, 46, 47, 48, 49 and 50 relative to Examples 38 SR.

[0160] The foregoing and other objects, features and advantages of the present invention will become more apparent from the following description of certain embodiments of the present invention by way of the following non-limiting examples.

EXAMPLES

[0161] The invention will now be described with reference to the following non-limiting experimental examples.

Example 1 (Comparative)—30 g Co/0.04 g Pt/100 g un-modified Al.SUB.2.O.SUB.3

[0162] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.04 g Pt/100 g support was prepared using an un-modified Al.sub.2O.sub.3 (Puralox with a surface area of 150 m.sup.2/g—hereinafter referred to as Puralox) support.

[0163] In a first impregnation step Co(NO.sub.3).sub.2.6H.sub.2O (79.0 g) and (NH.sub.4).sub.3Pt(NO.sub.3).sub.2 (0.026 g) were dissolved in distilled water (100 g). Maleic acid in the amount of about 0.03 moles/100 g support was dissolved in this solution. Puralox (100 g) was then added to this mixture and the excess water removed under reduced pressure using the drying profile in Table 1 to obtain a free flowing powder.

TABLE-US-00001 TABLE 1 Drying profile for impregnated support Temperature (° C.) Pressure (mbar) Time (min) 60 250 15 75 250 30 85 250 30 85 250-130 120 85 130-50  15 85  50 180

[0164] The free flowing powder was then calcined in a fluidised bed calciner with a heating ramp rate of 1° C./min to 250° C. with a hold time of 6 hours, using a GHSV of 2.5 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour.

[0165] Then, in a second impregnation stage, the above steps were repeated using Co(NO.sub.3).sub.2.6H.sub.2O (56.8 g) and [Pt(NH.sub.4).sub.4(NO.sub.3).sub.2] (0.042 g) dissolved in water (100 g). The previously calcined material (100 g) was added to this mixture and the excess water removed under reduced pressure using the drying profile in Table 1 to obtain a free flowing powder. The free flowing powder was then again calcined in a fluidised bed calciner with a heating ramp rate of 1° C./min to 250° C. with a hold time of 6 hours, using a GHSV of 2.5 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour.

Example 2 (Comparative)—30 g Co/0.04 g Pt/3.1 g Mn/100 g un-Modified Al.SUB.2.O.SUB.3 .(Mn as Promoter)

[0166] A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared as described in Example 1.

[0167] In this example, manganese was added as a catalyst promoter. After the second impregnation stage, Mn(NO.sub.3).sub.2.4H.sub.2O (10.1 g) was dissolved in water (100 g) and added to the calcined material (100 g). The excess water was removed under reduced pressure using the drying profile in Table 1 to obtain a free flowing powder. The free flowing powder was then again calcined in a fluidised bed calciner with a heating ramp rate of 1° C./min to 250° C. with a hold time of 6 hours, using a GHSV of 2.5 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour.

Example 3 (Comparative)—Ti—Al.SUB.2.O.SUB.3 .(Puralox) Support (Ti as Modifier)

[0168] Titanium(IV)iso-propoxide (17.2 g) was added to dry ethanol (78.9 g) and allowed to mix for 10 minutes. Al.sub.2O.sub.3 (Puralox) (100 g) was added to this solution and allowed to mix for a further 10 minutes. Following this, the ethanol was removed under reduced pressure using the drying profile in Table 2 to obtain a free flowing powder.

TABLE-US-00002 TABLE 2 Drying profile for the Ti impregnated Puralox material Pressure (mbar) Temperature (° C.) Time (min) 842 60 10 500 60 30 400 60 30 300 60 30 200 60 60 100 60 60 50 60 60

[0169] After the drying step, the modified support was calcined in a fluidized bed calciner with a GHSV of 2.5 Nm.sup.3/kg support/hour using air as the calcination gas using a heating rate of 1° C./min to 425° C. with no hold step at this temperature. After this fluidised bed calcination step, the support material was calcined further in a muffle oven to 550° C. at a heating rate of 5° C./min and a final hold time of 5 hours. The resulting modified support included 2.6 g Ti/100 g Al.sub.2O.sub.3.

Example 4 (Comparative)—Mn—Al.SUB.2.O.SUB.3 .(Puralox) Support (Mn as Modifier)

[0170] Manganese(II)acetate tetrahydrate (13.8 g) was dissolved in water (80-100 g) and mixed for 10 minutes. Al.sub.2O.sub.3 (Puralox) (100 g) was added to this solution and mixed for a further 10 minutes. Following this, the water was removed under reduced pressure using the drying profile in Table 3 to obtain a free flowing powder.

TABLE-US-00003 TABLE 3 Drying profile for the Mn impregnated Puralox material Pressure (mbar) Temperature (° C.) Time (min) 100 85 60 50 85 180

[0171] After the drying step, the modified support was calcined in a fluidized bed calciner with a GHSV of 2.5 Nm.sup.3/hour/kg support using air as the calcination gas using a heating rate of 1° C./min to 425° C. with no hold step at this temperature. After this fluidised bed calcination step, the respective support material was calcined further in a muffle oven to 550° C. at a heating rate of 5° C./min and a final hold time of 5 hours. The resulting modified support included 3.1 g Mn/100 g Al.sub.2O.sub.3.

Example 5 (Comparative)—MnTi—Al.SUB.2.O.SUB.3 .(Puralox) Support (Mn and Ti as Modifiers)

[0172] The Ti—Al.sub.2O.sub.3 support obtained from Example 3, was impregnated with manganese(II)acetate tetrahydrate as described in Example 4. The resulting modified support included 2.6 g Ti/3.1 g Mn/100 g Al.sub.2O.sub.3.

Example 6 (Comparative)—30 g Co/0.075 g Pt/100 g Ti—Al.SUB.2.O.SUB.3 .(Ti as Modifier)

[0173] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1, however, Ti—Al.sub.2O.sub.3 support as described in Example 3 was used.

Example 7 (Comparative)—30 g Co/0.075 g Pt/100 g Mn—Al.SUB.2.O.SUB.3 .(Mn as Modifier)

[0174] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1. However, no maleic acid was added during catalyst preparation. Mn—Al.sub.2O.sub.3 support as described in Example 4 was used.

Example 8 (Comparative)—30 g Co/0.075 g Pt/100 g MnTi—Al.SUB.2.O.SUB.3 .(Ti and Mn as Modifiers)

[0175] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1. However, no maleic acid was added during catalyst preparation. MnTi—Al.sub.2O.sub.3 support as described in Example 5, was used.

Example 9 (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g Ti—Al.SUB.2.O.SUB.3 .(Ti as Modifier and Mn as Promoter)

[0176] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/3.1 g Mn/100 g support was prepared as described in Example 2, however, Ti—Al.sub.2O.sub.3 support as described in Example 3, was used.

Example 10 (Comparative)—30 g Co/0.04 g Pt/100 g Si—Al.SUB.2.O.SUB.3 .(Si as Modifier)

[0177] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.04 g Pt/100 g support was prepared as described in Example 1. However, 2.1 g Si/100 g Al.sub.2O.sub.3 support was used, using TEOS (tetra ethoxy silane) as starting material for the support modification as described in U.S. Pat. No. 6,638,889.

Example 11 (Comparative)—30 g Co/0.04 g Pt/3.1 g Mn/100 g Si—Al.SUB.2.O.SUB.3 .(Si as Modifier and Mn as Promoter)

[0178] A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared as described in Example 10. However, during the second impregnation stage, Co(NO.sub.3).sub.2-6H.sub.2O (56.8 g), [Pt(NH.sub.4).sub.4(NO.sub.3).sub.2] (0.042 g) and Mn(NO.sub.3).sub.2.4H.sub.2O (11.6 g) was dissolved in water (100 g) and added to the calcined material obtained in the first impregnation stage (100 g).

Example 12 (Comparative)—30 g Co/0.075 g Pt/100 g Ti—Al.SUB.2.O.SUB.3 .(Ti as Modifier)

[0179] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1, however, no maleic acid was added during catalyst preparation. Ti—Al.sub.2O.sub.3 was used and was prepared as described in Example 3.

Example 13 (Comparative)—30 g Co/0.075 g Pt/100 g Ti—Al.SUB.2.O.SUB.3 .(Ti as Modifier)

[0180] A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared as described in Example 12. However, 5 g Ti/00 g Al.sub.2O.sub.3 support was used and was prepared as described in Example 3.

Example 14 (Comparative)—30 g Co/0.075 g Pt/100 g Ti—Al.SUB.2.O.SUB.3 .(Ti as Modifier)

[0181] A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared as described in Example 12. However, 10 g Ti/100 g Al.sub.2O.sub.3 support was used and was prepared as described in Example 3.

Example 15—Reduction

[0182] The calcined catalyst precursors were reduced prior to Fischer-Tropsch synthesis using pure H.sub.2 flowing at 2.0 Nm.sup.3/kg Catalyst/hour at atmospheric pressure. The following heating profile was used, 1° C./min to 110° C. hold 3 hours followed with, 1° C./min to 425° C. hold 10 hours. The reduced catalyst was cooled down to room temperature and suspended into molten wax and loaded in a CSTR under an inert gas blanket (argon or nitrogen).

Example 16—Fischer-Tropsch Synthesis

[0183] The activated and wax protected catalysts, as described in Example 15, were tested for their slurry phase FTS performance in a laboratory micro slurry CSTR at a reactor temperature of 230° C. and a reactor pressure of about 22 bar during which a pure H.sub.2 and CO and Ar feed gas mixture was utilised with a ˜5% Ar content and a total feed molar H.sub.2/CO ratio of about 1.8. This reactor was electrically heated and sufficiently high stirrer speeds were employed as to eliminate any gas-liquid mass transfer limitations. The feed gas space velocity was changed such that the syngas conversion was around 78±1%. The water partial pressure was about 10 bar.

[0184] Discussion

[0185] FIG. 1 shows the percentage difference in FT rate for Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9 and can be calculated as (FT rate of Ex. 1, 2, 6-8, 10, 11 or 33—FT rate of Ex. 9)/FT rate of Ex. 9. As can be seen, Example 2 (Co/3.1 g Mn/100 g un-modified Al.sub.2O.sub.3) shows that the addition of manganese as catalyst promoter did not improve the activity stability of the catalyst relative to Example 1 (the un-promoted and un-modified catalyst sample), with time on-line. This trend was also observed in comparing catalysts containing the Si-modified Al.sub.2O.sub.3 support, promoted with manganese as in Example 11 (Co/3.1 g Mn/100 g Si—Al.sub.2O.sub.3) with Example 10 (Co/100 g Si—Al.sub.2O.sub.3). Example 9 (Co/3.1 g Mn/100 g Ti—Al.sub.2O.sub.3) showed initial catalyst deactivation, however, after 5 days on-line the catalyst performance stabilized and remained stable over a 50 day period.

[0186] Example 6 (Co/100 g Ti—Al.sub.2O.sub.3) and Example 7 (Co/100 g Mn—Al.sub.2O.sub.3) showed that titanium and manganese as Al.sub.2O.sub.3 support modifiers respectively, resulted in an enhancement in activity and activity stability relative to Example 1, the un-promoted and un-modified catalyst sample.

[0187] Turning to Example 7, this Example showed black wax, which is an indication of catalyst break-up. This was not observed for the catalysts containing the combination of titanium and manganese support modifications (Example 8, Co/100 g MnTi—Al.sub.2O.sub.3).

[0188] The catalysts containing the combination of titanium and manganese, either manganese added as support modifier (Example 8) or catalyst promoter (Example 9), showed a significant enhancement in activity and activity stability relative to Examples 1, 2, 6, 7, 10 and 11.

[0189] The percentage difference in methane selectivity over the Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9, is shown in FIG. 2 and can be calculate as (% CH.sub.4 selectivity of Ex. 1, 2, 6-8, 10, 11 or 33—% CH.sub.4 selectivity of Ex. 9)/% CH.sub.4 selectivity of Ex. 9. As can be seen, Examples 8 and 9 containing the Mn/Ti combination showed lower and stable methane selectivity over time compared to the rest of the tested catalysts samples. Example 7, containing the Mn-modified Al.sub.2O.sub.3, showed initial low methane selectivity, which increased to the methane selectivity observed for Example 6, containing the Ti-modified Al.sub.2O.sub.3 support.

[0190] Table 4 below shows the FT performance over Examples 12-14 relative to the initial activities. These samples were prepared using Ti-modified Al.sub.2O.sub.3 with varying levels of Ti modification. As can be seen, increasing the Ti content from 2.6 g Ti/100 g Al.sub.2O.sub.3 to 10 g Ti/100 g Al.sub.2O.sub.3 did not result in a relative improvement in activity stability of the catalysts compared to that of Example 12. The catalysts containing the higher loading Ti resulted in lower activity stability with time on-line.

TABLE-US-00004 TABLE 4 The relative FT rate.sup.1 over Examples 12-14 tested under conditions as described in Example 16 Time Example 12, Example 13, Example 14, on-stream, 2.6 g Ti/100 g (5 g (10 g days Al.sub.2O.sub.3) Ti—Al.sub.2O.sub.3) Ti—Al.sub.2O.sub.3) 1 1 1 1 19 0.53 0.38 0.37 .sup.1Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) and Error is 5% e.g. 1 ± 0.05

Example 17—Fischer-Tropsch Synthesis

[0191] The activated and wax protected catalysts, as described in Example 15, for Examples 8 and 9 were tested for their slurry phase FTS performance in a laboratory micro slurry CSTR at a reactor temperature of 230° C. and a reactor pressure of about 19 bar during which a pure H.sub.2, CO and Ar feed gas mixture was utilised with a 10% Ar content and a total feed molar H.sub.2/CO ratio of ˜1.5.

[0192] This reactor was electrically heated and sufficiently high stirrer speeds were employed as to eliminate any gas-liquid mass transfer limitations. The feed gas space velocity was changed such that the syngas conversion was around 72±1%. The water partial pressure was about 6 bar.

[0193] Examples 8 and 9 were tested under the conditions described in Example 17. As can be seen from Table 5, Example 8, containing the MnTi support modification and Example 9 (containing Mn as promoter and Ti as support modifier) showed comparable relative FT activities and methane selectivities with time on-line, showing the beneficial effect of the combination of MnTi and adding Mn as catalyst promoter or support modifier under the FT conditions.

TABLE-US-00005 TABLE 5 FT performance over Examples 8 and 9 with time on- line under conditions as described in Example 17 Time on-stream, Relative FT Relative days rate.sup.1 CH.sub.4 selectivty.sup.2 Example 8, Co/MnTi—Al.sub.2O.sub.3 1 1 1 9 0.8 0.88 30 0.71 0.86 Example 9, CoMn/Ti—Al.sub.2O.sub.3 1 1 1 8 0.78 0.89 30 0.67 0.84 .sup.1Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) and Error is 5% e.g. 1 ± 0.05 .sup.2Drift in % CH.sub.4 selectivity relative to day 1; C % excluding CO.sub.2 formation and Error is 0.3 percentage points, e.g. 5.8 ± 0.3

Example 18 (Comparative)—30 g Co/0.075 g Pt/100 g Mn—Al.SUB.2.O.SUB.3

[0194] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1. However, no maleic acid was added during catalyst preparation. Mn—Al.sub.2O.sub.3 support as described in Example 4 was used. However, the resulting modified support consisted of 2.1 g Mn/100 g Al.sub.2O.sub.3.

Example 19 (Comparative)—30 g Co/0.075 g Pt/100 g Mn—Al.SUB.2.O.SUB.3

[0195] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1. However, no maleic acid was added during catalyst preparation. Mn—Al.sub.2O.sub.3 support as described in Example 4 was used. However, the resulting modified support consisted of 7.5 g Mn/100 g Al.sub.2O.sub.3.

Example 20 (Comparative)—30 g Co/0.075 g Pt/100 g Mn—Al.SUB.2.O.SUB.3

[0196] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 1. However, no maleic acid was added during catalyst preparation. Mn—Al.sub.2O.sub.3 support as described in Example 4 was used. However, the resulting modified support consisted of 10 g Mn/100 g Al.sub.2O.sub.3.

Example 21—Fischer-Tropsch Synthesis

[0197] The activated and wax protected catalysts, as described in Example 15, for Examples 18-20 were tested for their slurry phase FTS performance in laboratory micro slurry CSTR. The pressure was increased to 18 bar and the temperature to 230° C., where after the synthesis was introduced.

[0198] The synthesis feed gas consisted of hydrogen, carbon monoxide and it contained 10% argon as an internal standard with a total feed molar H.sub.2/CO ratio of ˜1.6. This reactor was electrically heated and sufficiently high stirrer speeds were employed so as to eliminate any gas-liquid mass transfer limitations. The % H.sub.2+CO conversion were maintained at 60%±2, by controlling the feed flow by means of Brooks mass flow controllers. The water partial pressure was about 5 bar.

[0199] Table 6 shows the relative FT performance over Examples 18-20. These samples were prepared using Mn-modified Al.sub.2O.sub.3 with varying levels of Mn modification. No beneficial effect was observed with the increased Mn content from 2.1 g Mn/100 g Al.sub.2O.sub.3 to 10 g Mn/100 g Al.sub.2O.sub.3. An increase in Mn levels resulted in a significant drift (decrease) in the FT rates with time on-stream.

TABLE-US-00006 TABLE 6 The relative FT rate.sup.1 over Examples 18-20 tested under conditions as described in Example 21 Time Example 18, Example 19, Example 20, on-line, (2.1 g Mn/100 g (7.5 g Mn/100 g (10 g Mn/100 g days Al.sub.2O.sub.3) Al.sub.2O.sub.3) Al.sub.2O.sub.3) 1 1 1 1 5 0.94 0.72 0.45 .sup.1Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) and Error is 5% e.g. 1 ± 0.05

Example 22 (Comparative)—MnSi—Al.SUB.2.O.SUB.3 .(Puralox) Support

[0200] The Si—Al.sub.2O.sub.3 support as described in Example 10 was impregnated with manganese(II)acetate tetrahydrate as described in Example 4. The resulting modified support consisted of 3 g Mn/100 g SiAl.sub.2O.sub.3.

Example 23 (Comparative)—MnSi—Al.SUB.2.O.SUB.3 .(Puralox) Support

[0201] The Si—Al.sub.2O.sub.3 support as described in Example 10 was impregnated with manganese(II)acetate tetrahydrate as described in Example 4. The resulting modified support consisted of 5 g Mn/100 g Si—Al.sub.2O.sub.3.

Example 24 (Conductivity Measurements)

[0202] Alumina dissolves in an aqueous medium at low pH. The dissolution of alumina results in the formation of aluminium ions. As more and more alumina dissolves, the concentration of aluminium increases with time. An increase in aluminium with time was followed by monitoring the conductivity at a constant pH of 2. The pH was kept constant by automated addition of a 10% nitric acid solution. The results are given in FIG. 3 for the modified and un-modified Al.sub.2O.sub.3.

[0203] The Ti (Example 3), Mn (Example 4) and Si modified Al.sub.2O.sub.3 supports exhibited very similar Al-dissolution behaviour over time. The MnSi modification of the Al.sub.2O.sub.3 (Example 22) resulted in a decrease in the Al-dissolution. However, a further increase in the Mn loading (Example 23) negated the suppression of the Al-dissolution and resulted in the Al-dissolution behaviour similar to the Si-modified Al.sub.2O.sub.3 support. Surprisingly, it can be seen that over the MnTi-modified support (Example 5) the Al-dissolution was significantly suppressed relative to the MnSi modified Al.sub.2O.sub.3 (Example 22).

Example 25 (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.SUB.2.O.SUB.3.) (Co-Hydrolysis, Ti as Modifier and Mn as Promoter), C4639

[0204] A cobalt based Fisher-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.sub.2O.sub.3) was prepared as described in Example 9, however the Ti—Al.sub.2O.sub.3 support used in Example 9 was replaced with a titanium-containing support that was prepared via co-hydrolysis of titanium (IV) 2-ethylhexoxide and Al-hexanolate as described in Example 37 of WO 2014020507.

Example 26 (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.SUB.2.O.SUB.3 .(Calcined PURAL 200™ as the Support, Slurry Impregnated Ti as Modifier and Mn as Promoter), C4685

[0205] A cobalt based Fisher-Tropsch synthesis catalyst precursor was prepared with the composition 30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.sub.2O.sub.3) as described in Example 9, however, the Puralox used in Example 9 was replaced with calcined PURAL 200™ which has a pore diameter similar to the pore diameter of the support of Example 25 and has a surface area of about 90 m.sup.2/g.

Example 27—Reduction and Fischer-Tropsch Synthesis (FTS)

[0206] The calcined catalyst precursors of Examples 25 and 26 were reduced and suspended into molten wax as described in Example 15. The FTS performance of the activated and wax protected catalysts of Examples 25 and 26 were evaluated in a fix bed reactor at 230° C. and a reactor pressure of about 16 bar utilizing a feed gas mixture with an inlet molar H.sub.2/CO ratio of about 1.6. The feed gas space velocity was changed such that the syngas conversion was ˜62%-65%.

[0207] Discussion

[0208] Table 7 shows that similar FTS catalyst performance results were obtained in comparing the Co/Pt/Mn/Ti—Al.sub.2O.sub.3 catalyst sample prepared via co-hydrolysis of the Ti-modified support (Example 25) with Example 26 (slurry impregnation of Ti), demonstrating that co-hydrolysis of the Ti-modified support is an alternative to slurry impregnation of titanium on alumina.

TABLE-US-00007 TABLE 7 FT performance over Examples 25 and 26 under conditions as described in Example 27 CH.sub.4 selectivity.sup.1 Example 25, Example 26, % difference in C4639.sup.2 C4685.sup.2 absolute CH.sub.4 Time Co/Pt/Mn/ Co/Pt/Mn/ selectivity on-line, Ti—Al.sub.2O.sub.3 with Ti—Al.sub.2O.sub.3 with between days co-hydrolysis slurry impregnation Ex. 25 and Ex. 26.sup.3 1 1.00 1.00 0.06 2 1.00 1.02 0.03 3 1.01 1.01 0.07 7 1.05 % difference in absolute FT rates between Relative FT rate.sup.4 Ex. 25 and Ex. 26.sup.5 1 1.00 1.00 0.14 2 0.97 0.97 0.15 3 0.93 0.94 0.13 7 0.88 .sup.1C % excluding CO.sub.2 formation .sup.2Drift in % CH.sub.4 selectivity relative to day 1 .sup.3% CH.sub.4 selectivity (sel) difference between Ex. 25 and Ex. 26 = (% CH.sub.4 sel of Ex. 25 − % CH.sub.4 sel of Ex. 26)/% CH.sub.4 sel of Ex. 26 .sup.4Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) .sup.5% difference in FT rates between Ex. 25 and Ex. 26 = (FT rate of Ex. 25 − FT rate of Ex. 26)/FT rate of Ex. 26

Example 28: (Comparative)—30 g Co/0.075 g Pt/5 g Ni/100 g (2.6 g Ti/100 g Al.SUB.2.O.SUB.3.) (Ti as Modifier and Ni as Promoter), C4140

[0209] Co(NO.sub.3).sub.2.6H.sub.2O (11.9 g), (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 (0.0075 g) and Ni(NO.sub.3).sub.2.6H.sub.2O (1.9 g) were dissolved in water (13 ml for Co, 2 ml for Pt, 2 ml for Ni). The pH of the solution was adjusted to 2.3 using diluted nitric acid. 15 g of the Ti-modified Puralox support as described in Example 3 was added and the excess water removed under reduced pressure using the drying profile in Table 8 to obtain a free flowing powder.

TABLE-US-00008 TABLE 8 Drying profile Pressure (mbar) Temperature (° C.) Time (min) Atmospheric 60 10 280 60 30 280 75 90 280 85 60 50 85 60 50 90 120

[0210] 20 g of the free flowing sample was calcined in a vertical furnace using an air flow of 1000 ml/min and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours. The above steps were repeated in a second impregnation stage by dissolving Co(NO.sub.3).sub.2.6H.sub.2O (6.8 g), (NH).sub.4Pt(NO).sub.2 (0.01 g) and Ni(NO.sub.3).sub.2.6H.sub.2O (1.2 g) in water (9 ml for Co, 2 ml for Pt, 3 ml for Ni). The previously calcined (first impregnation stage) material (12 g) was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 8. 15 g of the free flowing sample was calcined in a vertical furnace using an air flow of 750 ml/min and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

Example 29: (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.SUB.2.O.SUB.3.) (Ti as Modifier and Mn as Promoter—Similar to Example 9, but with Smaller Quantities and Different Drying Profile), C4144

[0211] Co(NO).sub.2.6H.sub.2O (13.3 g) and (NH).sub.4Pt(NO).sub.2 (0.0075 g) were dissolved in water (13 ml for Co, 3 ml for Pt). The pH of the solution was adjusted to 2.3 using diluted nitric acid. 15 g of the Ti-modified Puralox support as described in Example 3 was added and the excess water removed under reduced pressure using the drying profile in Table 9 to obtain a free flowing powder.

TABLE-US-00009 TABLE 9 Drying profile Pressure (mbar) Temperature (° C.) Time (min) Atmospheric 60 10 280 60 30 250 75 30 250 85 30 250-130 85 120 gradient 130-50  85  15 gradient  50 85 180 

[0212] 20 g of the free flowing sample was calcined in a vertical furnace using an air flow of 1000 ml/min and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours. In a second impregnation stage, the above steps were repeated using Co(NO.sub.3).sub.2.6H.sub.2O (5.75 g) and (NH).sub.4Pt(NO).sub.2 (0.01 g) as well as Mn(NO.sub.3).sub.2.4H.sub.2O (1.4 g) by dissolving it in water (10 ml for Co, 2 ml for Pt, 3 ml for Mn). 12 g of the first impregnation stage calcined material was added to the mixture and the excess water was removed under reduced pressure using the drying profile of Table 9 to obtain a free flowing powder. 15 g free flowing sample was calcined in a vertical furnace using an air flow of 750 ml/min and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

Example 30—Reduction and Fischer-Tropsch Synthesis (FTS)

[0213] The calcined catalyst precursors of Examples 28 and 29 were reduced and suspended into molten wax as described in Example 15. The FTS performance of the activated and wax protected catalysts of Examples 28 and 29 were evaluated in a fix bed reactor at 230° C. as described in Example 27.

[0214] Discussion

[0215] It is known that nickel can be a used as an activity stability promoter [Ind. Eng. Chem. Res. 2010, 49, 4140-4148 and U.S. Pat. No. 8,143,186]. However, the addition of Ni as promoter to the Co/Pt/Ti-A.sub.2O.sub.3 FTS catalyst did not demonstrate the same Co FTS catalyst performance as when Mn was used as promoter. Mn as promoter resulted in lower methane selectivity with higher activity compared to Ni as promoter. Table 10 illustrates the extent of deactivation of the catalysts as described in Example 28 and Example 29 relative to its initial activity as well as the drift in methane selectivity obtained over catalysts as prepared in Example 28 and 29 and activated and tested as described in Example 30 relative to its initial methane selectivity.

TABLE-US-00010 TABLE 10 FTS performance over Example 28 (Co/Pt/Ni//Ti—Al.sub.2O.sub.3) and Example 29 (Co/Pt/Mn/Ti—Al.sub.2O.sub.3) with time-on-line under conditions as described in Example 30 CH.sub.4 selectivity.sup.1 Example 28, Example 29, % difference in Time C4140.sup.2 C4144.sup.2 absolute CH.sub.4 on-line, Co/Pt/Ni/ Co/Pt/Mn/ selectivity between days Ti—Al.sub.2O.sub.3 Ti—Al.sub.2O.sub.3 Ex. 28 and Ex. 29.sup.3 1 1.00 1.00 0.78 3 0.94 1.03 0.64 5 0.93 1.04 0.59 10 1.04 % difference in absolute FT rates between Relative FT rate.sup.4 Ex. 28 and Ex. 29.sup.5 1 1.00 1.00 −0.27 3 1.10 0.93 −0.14 5 1.17 0.92 −0.08 10 0.88 .sup.1C % excluding CO.sub.2 formation .sup.2Drift in % CH.sub.4 selectivity relative to day 1 .sup.3% CH.sub.4 selectivity (sel) difference between Ex. 28 and Ex. 29 = (% CH.sub.4 sel of Ex. 28 − % CH.sub.4 sel of Ex. 29)/% CH.sub.4 sel of Ex. 29 .sup.4Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) .sup.5% difference in FT rates between Ex. 28 and Ex. 29 = (FT rate of Ex. 28 − FT rate of Ex. 29)/FT rate of Ex. 29

Example 31: (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g (2.6 g Ti/100 g Al.SUB.2.O.SUB.3.) with Ti as Modifier and Mn as Promoter Using a Hydrothermal Deposition Method (HDM), C4585

[0216] Co(NO.sub.3).sub.2.6H.sub.2O (37.2 g), (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 (0.07 g), Mn(NO.sub.3).sub.2.4H.sub.2O (7.06 g) and maleic acid (1.25 g) were dissolved in 75 ml water. Cobalt hydroxide (3 g) was added to the nitrate solution where after 50 g of the Ti-modified Puralox support as described in Example 3 was added. An additional 3 g of Co(OH).sub.2 was added to the slurry and mixed at 95° C. in a rotary evaporator at 65 rpm. Additional 3 g of Co(OH).sub.2 was added until the desired loading of 11.8 g was reached. The mixture was stirred until complete absorption of Co(OH).sub.2 (for approximately 3 hours). The excess water was removed under reduced pressure using the drying profile of Table 11 to obtain a free flowing powder and calcined at 250° C. at a heating rate of 1° C./min in air (2500 ml/min/gcat) for 6 hours.

TABLE-US-00011 TABLE 11 Drying profile Pressure (mbar) Temperature (° C.) Time (min) 500-130 95 180 50 100 120

[0217] The calcined catalyst precursor was reduced and suspended into molten wax as described in Example 15. The catalyst was tested for its slurry phase FTS performance in a laboratory micro slurry CSTR as described in Example 17.

[0218] As can be seen from Table 12, Example 31, prepared using HDM, showed lower methane selectivity and higher activity when comparing to the absolute CH.sub.4 selectivity and reaction rates of Example 9 (the cobalt nitrate slurry impregnation method). The drift in methane selectivity of Example 31 is slightly more than Example 9, but the deactivation relative today 1 over time on stream of Example 31 and Example 9 are comparable.

TABLE-US-00012 TABLE 12 FTS performance over Example 31 (Co/Pt/Mn/Ti—Al.sub.2O.sub.3 - prepared using HDM) with time-on-line under conditions as described in Example 17) CH.sub.4 selectivity.sup.1 Example 31, % difference in C4585.sup.2 Example 9, absolute CH.sub.4 Time Co/Pt/Mn/ C2155.sup.2 selectivity on-line, Ti—Al.sub.2O.sub.3 Co/Pt/Mn/ between days (HDM) Ti—Al.sub.2O.sub.3 Ex. 31 and Ex. 9.sup.3 1 1.00 1.00 −0.15 17 0.85 0.89 −0.19 31 0.76 0.86 −0.26 % difference in absolute FT rates between Relative FT rate.sup.4 Ex. 31 and Ex. 9.sup.5 1 1.00 1.00 0.21 17 0.66 0.70 0.15 31 0.66 0.70 0.15 .sup.1C % excluding CO.sub.2 formation .sup.2Drift in % CH.sub.4 selectivity relative to day 1 .sup.3% CH.sub.4 selectivity (sel) difference between C4585 and C2155 = (% CH.sub.4 sel of C4585 − % CH.sub.4 sel of C2155)/% CH.sub.4 sel of C2155 .sup.4Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) .sup.5% difference in FT rates between C4585 and C2155 = (FT rate of C4585 − FT rate of C2155)/FT rate of C2155

Example 32: (Comparative)—MnTi—SiO.SUB.2 .(Mn and Ti as Support Modifiers on a Silica Support)—(FSQ-15)

[0219] Titanium (IV)iso-propoxide (17.2 g) was added to dry ethanol (78.9 g) and allowed to mix for 10 minutes. Amorphous, preshaped silica-gel (100 g), CARiACT Q-15 (an average pore diameter of 15 nm), as obtained from Fuji Silysia Chemical LTD, was added to this solution and allowed to mix for a further 10 minutes. The ethanol was removed under reduced pressure using the drying profile in Table 2 to obtain a free flowing powder.

[0220] Manganese(II)acetate tetrahydrate (13.8 g Mn(Ac).sub.2.4H.sub.2O for 3.1 g Mn loading) was dissolved in water (80-100 g) and allowed to mix for 10 minutes. The free flowing powder obtained from the Ti(OPr).sub.4 modified silica (100 g) was added to this solution and allowed to mix for a further 10 minutes. The water was removed under reduced pressure using the drying profile in Table 3 to obtain a free flowing powder. After the drying step, the modified support was calcined in a fluidised bed with a GHSV of 2.5 Nm.sup.3/kg support/hour using air as calcination gas at a heating rate of 1° C./min to 425° C. The support material was further calcined in a muffle oven to 500-550° C. at a heating rate of 5° C./min and a final hold time of hours. The resulting modified support included 3.1 g Mn/2.6 g Ti/100 g SiO.sub.2.

Example 33: (Comparative)—30 g Co/0.075 g Pt/100 g (3.1 g Mn/2.6 g Ti/100 g SiO.SUB.2.) (Mn and Ti as Support Modifiers), (FSQ-15), C4859

[0221] In a first impregnation step, Co(NO.sub.3).sub.2.6H.sub.2O (39.5 g) and (NH.sub.4).sub.3Pt(NO.sub.3).sub.2 (0.025 g) were dissolved in water (50 g). The pH of the solution was adjusted to 2.3 using diluted nitric acid. The MnTi—SiO.sub.2 (50 g) support as described in Example 32 was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 1 to obtain a free flowing powder. The free flowing powder was calcined in a fluidized bed calciner with a heating ramp rate of 1° C./min to 250° C. with a hold time of 6 hours using a GHSV of 2.5 Nm.sup.3/kg(Co(NO.sub.3).sub.2.6H.sub.2O)/hour.

[0222] In a second impregnation step, Co(NO.sub.3).sub.2.6H.sub.2O (28.4 g) and (NH.sub.4).sub.3Pt(NO.sub.3).sub.2 (0.04 g) were dissolved in water (50 g). The pH of the solution was adjusted to 2.3 using diluted nitric acid. The calcined material of the first impregnation step (50 g) was then added to this mixture and the excess water was removed under reduced pressure using the drying profile in Table 1 to obtain a free flowing powder. The free flowing powder was calcined in a fluidized bed calciner with a heating ramp rate of 1° C./min to 250° C. with a hold time of 6 hours using a GHSV of 2.5 Nm.sup.3/kg(Co(NO.sub.3).sub.2.6H.sub.2O)/hour.

[0223] The calcined catalyst material was reduced and suspended into molten wax as described in Example 15. The catalyst was tested for its slurry phase FTS performance in a laboratory micro slurry CSTR as described in Example 17.

[0224] Discussion

[0225] As mentioned before, FIG. 1 shows the difference in FT rate for Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9. The Mn/Ti combination on a silica support (Example 33) also demonstrated a significant enhancement in activity compared to the comparative examples that do not comprise of the Mn/Ti combination.

[0226] As mentioned before, FIG. 2 shows the difference in percentage methane selectivity for Examples 1, 2, 6-8, 10, 11 and 33 relative to Example 9. Example 33 containing the Mn/Ti combination on a silica support showed the lowest methane selectivity over time compared to the rest of the tested catalysts samples.

Example 34: (Comparative)—MnTi—SiO.SUB.2 .(FSQ-6)

[0227] A modified support with the composition 3.1 g Mn/2.6 g Ti/100 g SiO.sub.2 was prepared as described in Example 32, however, the support was replaced with CARiACT Q-6 with an average pore diameter of 6 nm.

Example 35: (Comparative)—MnTi—SiO.SUB.2 .(FSQ-30)

[0228] A modified support with the composition 3.1 g Mn/2.6 g Ti/100 g SiO.sub.2 was prepared as described in Example 32, however, the support was replaced with CARiACT Q-30 with an average pore diameter of 30 nm.

Example 36: (Comparative)—MnTi—SiO.SUB.2 .(FSQ-50)

[0229] A modified support with the composition 3.1 g Mn/2.6 g Ti/100 g SiO.sub.2 was prepared as described in Example 32, however, the support was replaced with CARiACT Q-50 with an average pore diameter of 50 nm.

Example 37: (Comparative)—30 g Co/0.075 g Pt/100 g MnTi—SiO.SUB.2 .(FSQ-6), C4881

[0230] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 33, however, MnTi—SiO.sub.2 (FSQ-6) support as described in Example 34 was used.

Example 38: (Inventive)—30 g Co/0.075 g Pt/100 g MnTi—SiO.SUB.2 .(FSQ-30), C4812

[0231] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 33, however, MnTi—SiO.sub.2 (FSQ-30) support as described in Example 35 was used.

Example 39: (Comparative)—30 g Co/0.075 g Pt/100 g MnTi—SiO.SUB.2 .(FSQ-50), C4860

[0232] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as described in Example 33, however, MnTi—SiO.sub.2 (FSQ-50) support as described in Example 36 was used.

Example 40: (Inventive)—30 g Co/0.075 g Pt/2.5 g MAc/100 g MnTi—SiO.SUB.2 .(FSQ-30), C4987

[0233] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g MnTi—SiO.sub.2 (FSQ-30) support was prepared as described in Example 38, however, maleic acid (MAc) (1.25 g) was added to the solution during the first impregnation step.

Example 41: (Comparative)—30 g Co/0.075 g Pt/100 g SiO.SUB.2 .(FSQ-30), C4408 (Unmodified SiO.SUB.2

[0234] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/100 g support was prepared as follows using FSQ-30 as support.

[0235] Co(NO).sub.2.6H.sub.2O (11.8 g) and (NH.sub.4).sub.3Pt(NO).sub.2 (0.0075 g) were dissolved in distilled water (15 ml for Co, 2 ml for Pt). FSQ-30 silica (15 g) was added to this mixture and the excess water removed under reduced pressure using the drying profile in Table 13 to obtain a free flowing powder.

TABLE-US-00013 TABLE 13 Drying profile Temperature (° C.) Pressure (mbar) Time (min) 60 No Vacuum 10 60 280 30 75 280 90 85 280 60 85  50 180

[0236] 17 g of the free flowing sample was calcined in a vertical furnace using an air flow of 700 ml/min (GHSV=2.500 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

[0237] The above steps were repeated in a second impregnation stage by dissolving Co(NO.sub.3).sub.2.6H.sub.2O (6.8 g) and (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 (0.0098 g) in water (12 ml for Co, 2 ml for Pt). The previously calcined (first impregnation stage) material (12 g) was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 13. 15 g of the free flowing sample was calcined in a vertical furnace using an air flow of 680 ml/min (GHSV=2.700 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

Example 42 (Comparative)—30 g Co/0.075 g Pt/3.1 g Mn/100 g SiO.SUB.2 .(FSQ-30), C4404, (Mn as Promoter)

[0238] Co(NO.sub.3).sub.2.6H.sub.2O (9.4 g), (NH.sub.4).sub.3Pt(NO.sub.3).sub.2 (0.006 g) and Mn(NO.sub.3).sub.2.4H.sub.2O (1.7 g) were dissolved in distilled water (10 ml for Co, 1 ml for Pt and 2 ml for Mn). Unmodified FSQ-30 silica (12 g) was added to this mixture and the excess water removed under reduced pressure using the drying profile in Table 13 to obtain a free flowing powder. 15 g of the free flowing sample was calcined in a vertical furnace using an air flow of 620 ml/min (GHSV=2.500 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

[0239] The above steps were repeated in a second impregnation stage by dissolving Co(NO.sub.3).sub.2.6H.sub.2O (5.7 g) and (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 (0.0081 g) in water (10 ml for Co, 1 ml for Pt). The previously calcined (first impregnation stage) material (10 g) was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 13. 11 g of the free flowing sample was calcined in a vertical furnace using an air flow of 500 ml/min (GHSV=2.700 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

Example 43 (Comparative)—3.1 g Mn/100 g SiO.SUB.2 .(FSQ-30) (Mn as Support Modifier)

[0240] A manganese modified support was prepared as described in Example 4, however, silica (FSQ-30) (100 g) was used as support. The resulting modified support included 3.1 g Mn/100 g SiO.sub.2.

Example 44 (Comparative)—30 g Co/0.075 g Pt/2.5 g MAc/100 g Mn—SiO.SUB.2 .(FSQ-30), C4998 (Mn as Support Modifier and MAc)

[0241] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/2.5 g MAc/100 g support was prepared as described in Example 40, however, Mn—SiO.sub.2 (50 g) modified support as described in Example 43 was used.

Example 45 (Comparative)—2.6 g Ti/100 g SiO.SUB.2 .(FSQ-30), (Ti as Support Modifier)

[0242] A titanium modified support was prepared as described in Example 3, however, FSQ-30 silica (100 g) was used as support. The resulting modified support included 2.6 g Ti/100 g SiO.sub.2.

Example 46 (Comparative)—30 g Co/0.075 g Pt/100 g Ti—SiO.SUB.2 .(FSQ-30), C4410

[0243] Co(NO.sub.3).sub.2.6H.sub.2O (11.8 g) and (NH.sub.4).sub.3Pt(NO.sub.3).sub.2 (0.0075 g) were dissolved in water (15 ml for Co, 2 ml for Pt). The Ti—SiO.sub.2 (15 g) support as described in Example 45 was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 13 to obtain a free flowing powder. 17 g of the free flowing sample was calcined in a vertical furnace using an air flow of 700 ml/min (GHSV=2.500 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

[0244] The above steps were repeated in a second impregnation stage by dissolving Co(NO.sub.3).sub.2.6H.sub.2O (6.8 g) and (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 (0.0098 g) in water (12 ml for Co, 2 ml for Pt). The previously calcined (first impregnation stage) material (12 g) was added to the mixture and the excess water removed under reduced pressure using the drying profile in Table 13. 15 g of the free flowing sample was calcined in a vertical furnace using an air flow of 680 ml/min (GHSV=2.700 Nm.sup.3/kgCo(NO.sub.3).sub.2.6H.sub.2O/hour) and a heating rate of 1° C./min to 250° C. with a hold time of 6 hours.

Example 47 (Comparative)—30 g Co/0.075 g Pt/2.5 g MAc/100 g Ti—SiO.SUB.2 .(FSQ-30), C4997

[0245] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/2.5 g MAc/100 g support was prepared as described in Example 40, however, the Ti-modified silica support as described in Example 45 was used.

Example 48 (Inventive)—30 g Co/0.075 g Pt/2.5 g MAc/3.1 g Mn/100 g Ti—SiO.SUB.2 .(FSQ-30), C4991 (Mn as Promoter in First Impregnation)

[0246] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/2.5 MAc/100 g Ti—SiO.sub.2 (FSQ-30) was prepared as described in Example 47, however, in this example manganese was added as a catalyst promoter in the first impregnation stage prior to pH adjustment by means of dissolving Mn(NO.sub.3).sub.2.4H.sub.2O (7.1 g) in water (100 g).

Example 49 (Inventive)—30 g Co/0.075 g Pt/2.5 g MAc/3.1 g Mn/100 g Ti—SiO.SUB.2 .(FSQ-30), C4990 (Mn as Promoter in Second Impregnation)

[0247] A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 g Co/0.075 g Pt/2.5 MAc/100 g Ti—SiO.sub.2 (FSQ-30) was prepared as described in Example 47, however, in this example manganese was added as a catalyst promoter in the second impregnation stage prior to pH adjustment by means of dissolving Mn(NO.sub.3).sub.2.4H.sub.2O (7.1 g) in water (100 g).

Example 50 (Inventive)—30 g Co/0.075 g Pt/3.1 g Mn/100 g Ti—SiO.SUB.2 .(FSQ-30), C4996 (Mn as Promoter in First Impregnation)

[0248] A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared as described in Example 48, however, in this example no maleic acid was added during the catalyst preparation.

Example 51—Standard Reduction (SR)

[0249] The silica supported calcined catalyst materials in Examples 33, 37-42, 44 and 46-50 were reduced in situ prior to Fischer-Tropsch synthesis using pure H.sub.2 flowing at 2.0 Nm.sup.3/kg catalyst/hour at atmospheric pressure. The temperature was ramped at 1° C./min to 385° C.-425° C. and maintained for 6 hours.

Example 52—Reduction—Carbiding—Reduction Activation (RCR)

[0250] The silica supported calcined catalyst materials in Examples 33 and 37-39 were activated in situ prior to Fischer-Tropsch synthesis in a fixed bed reactor by means of the following procedure: [0251] Increasing the temperature to 380° C. at 1° C./min in hydrogen (4 500 ml/gcat/h) under atmospheric pressure and maintain for 6 hours, followed by cooling down to 200° C. in hydrogen. [0252] Replacing hydrogen with argon (2 000 ml/gcat/h) and hold for 20 minutes. [0253] In the carbide formation step, replace argon with CO (6 000 ml/gcat/h) and start increasing the temperature to 230° C. at 1° C./min and maintain for 6 hours at 6 bar CO. [0254] Whilst cooling under CO (1 000 ml/gcat/h) from 230 to 170° C. the pressure is dropped to atmospheric pressure. [0255] At 170° C. and atmospheric pressure, the CO was replaced with argon (20 min; 2 000 ml/gcat/h) where after the argon was again replaced by hydrogen. [0256] In an activation step, increasing the temperature to 425° C. under hydrogen (8 000 ml/gcat/h) at 1° C./min and at a hold time of 7 hours, followed by cooling down to 200° C. in hydrogen after which FTS was started.

Example 53—Fischer-Tropsch Synthesis

[0257] The FTS performance of the activated silica supported catalysts of Examples 33, 37-42, 44 and 46-50 were evaluated in a fix bed reactor at 230° C. and 17 bar pressure. The inlet H.sub.2/CO ratio was ˜1.6. The feed gas space velocity was changed as such to control the syngas conversion at roughly 50%-55%.

[0258] Discussion

[0259] Pore Diameter: Standard Reduction (SR)

[0260] FIG. 4 and FIG. 5 show the difference in FT rates and percentage CH.sub.4 selectivity of Example 33 (FSQ-15), Example 37 (FSQ-6) and Example 39 (FSQ-50) relative to Example 38 (FSQ-30) (activated at 385° C. with standard reduction as described in Example 51).

[0261] Example 38 with an average pore diameter of 30 nm, following standard reduction, demonstrated the highest FT rates when compared to the other catalysts following standard reduction. The catalysts with the larger average support pore diameters of 30 nm and 50 nm had the lowest CH.sub.4 selectivity, however, from FIG. 6 it can be seen that the best FTS activity/C5+ selectivity combination (C5+ productivity) is obtained over the Fischer-Tropsch catalyst as described in Example 38 (FSQ-30). The C5+ productivity of the Fischer-Tropsch catalyst as described in Example 37 (FSQ-6) and Example 39 (FSQ-50) was much lower (see FIG. 6).

[0262] As mentioned herein before, the C5+ productivity is the unit mass of C5+ hydrocarbons per unit catalyst per unit time and is a function of the rate of CO converted and the C5+ hydrocarbon selectivity of the catalyst.

[0263] Pore Diameter: RCR Activation

[0264] FIG. 4 and FIG. 5 show the difference in FT rates and percentage CH.sub.4 selectivity of Example 33 (FSQ-15), Example 37 (FSQ-6) and Example 39 (FSQ-50) relative to Example 38 (FSQ-30) (activated at 385° C. with standard reduction as described in Example 51).

[0265] RCR activation of the silica supported catalysts improved the activities and selectivity of the catalysts further. The RCR activated Fischer-Tropsch catalyst demonstrated an even bigger differentiation in the C5+ productivity for the catalyst as described in Example 38 with a support pore diameter of 30 nm (see FIG. 6).

[0266] Maleic Acid (MAc) Addition

[0267] The CH.sub.4 selectivity obtained over the catalyst where maleic acid was added during the first impregnation step as described in Example 40 (30 g Co/0.075 g Pt/2.5 g MAc/100 g MnTi—SiO.sub.2 (FSQ-30)) was comparable with the catalyst CH.sub.4 selectivity of the catalyst as described in Example 38 on similar support pore diameters (FSQ-30) (see Table 14). However, the activity and activity stability of the catalyst as described in Example 40 was higher and may be as a result of improved metal dispersion with the maleic acid addition.

TABLE-US-00014 TABLE 14 Difference in FTS performance between Example 38 and Example 40 (similar support pore diameter) following standard reduction under conditions as described in Example 50. Relative CH.sub.4 selectivity, %.sup.1 Example 40, Example 38, Difference in Time C4987.sup.2 C4812.sup.2 CH.sub.4 selectivity of on-line, Co/Pt/MAc/ Co/Pt/ Ex. 40 relative days MnTi—SiO.sub.2 MnTi—SiO.sub.2 to Ex. 38 .sup.3 1 1.00 1.00 −0.13 2 0.97 0.90 −0.05 3 0.99 0.91 −0.05 4 1.00 0.87 0.00 5 1.01 0.85 0.04 Relative FT rate.sup.4 Example 40, Example 38, difference in Time C4987 C4812 FT rate of on-line, Co/Pt/MAc/ Co/Pt/ Ex. 40 relative days MnTi—SiO.sub.2 MnTi—SiO.sub.2 to Ex. 38 .sup.5 1 1.00 1.00 −0.09 2 0.97 0.86 0.02 3 0.96 0.85 0.03 4 0.95 0.80 0.09 5 0.95 0.79 0.09 .sup.1C % excluding CO.sub.2 formation .sup.2Drift in % CH.sub.4 selectivity relative to day 1 .sup.3 % CH.sub.4 sel difference between Ex. 40 & Ex. 38 = (% CH.sub.4 sel of Ex. 40 − % CH.sub.4 sel of Ex. 38)/% CH.sub.4 sel of Ex. 38 .sup.4Relative to the initial FT rate ((CO + CO.sub.2) μmol/CO/gs)) .sup.5 Difference in FT rates between Ex. 40 & Ex. 38 = ((FT rate of Ex. 40 − FT rate of Ex. 38)/FT rate of Ex. 38)

[0268] MnTi—SiO.sub.2 Support

[0269] The combination of Ti and Mn is crucial for high Fischer-Tropsch activity and low CH.sub.4 selectivity (see FIG. 7 and FIG. 8). Modification of the silica support with Mn only (Example 44) or as a promoter (Example 42) resulted in a catalyst with lower Fischer-Tropsch performance compared to an unmodified silica support (Example 41). The use of Ti as a support modifier (Example 46 and Example 47 (with MAc)) for the Co Fischer-Tropsch catalyst demonstrated higher Fischer-Tropsch rates relative to the unmodified support (Example 41). However, the CH.sub.4 selectivity was not significantly improved when using Ti as a support modifier when compared to an unmodified silica support. When using Ti as a support modifier in combination with Mn (either as support modifier as in Example 38 and Example 40 (with MAc) or as a promoter as in Examples 48, 49 and 50) the CH.sub.4 selectivity obtained over these catalysts are the lowest. The use of Mn as a support modifier (Example 38 and Example 40 (with MAc)) resulted in higher FT rates compared to the use of Mn as a promoter (Examples 48, 49 and 50).

Example 54—Attrition Resistance

[0270] The attrition resistance of the MnTi—SiO.sub.2 (FSQ-30) catalyst support as described in Example was compared to the unmodified FSQ-30 support to determine the physical strength of the modified catalyst support.

[0271] A Silverson Homogenizer was used to perform the shear attrition test. Catalyst support (5 g) as described in Example 35 was added to 170 ml distilled water and stirred for 15 minutes at a stirrer speed of 1000 rpm at 25° C. After completion of the shear attrition test the entire sample/mixture was decanted and the PSD (particle size distribution) was measured with a Saturn Digisizer, which is essentially a volume-based technique used to determine the PSD before and after shear testing.

[0272] Discussion

[0273] The mechanical strength of the modified support as described in Example 35 is shown in Table 15. Mechanical attrition testing indicated that Ti/Mn modified silica is mechanically robust when compared to the unmodified silica with the same pore diameter of 30 nm. The Ti and Mn modifiers therefore improved the mechanical integrity to withstand fracturing of the particles.

TABLE-US-00015 TABLE 15 PSD before and after shear testing indicating relative change in volume based mean for Ti/Mn modified silica compared to the unmodified analogue. Unmodified silica Ti/Mn modified silica (30 nm pore diameter) (30 nm pore diameter) Shear Δ mean 16.3 0.3

Example 55—Slurry Phase Fischer-Tropsch Synthesis in NH.SUB.3 .Poison Gas

[0274] The Fischer-Tropsch catalyst performance of the catalyst as described in Example 40 (30 g Co/0.075 g Pt/2.5 g MAc/100 g MnTi—SiO.sub.2 (FSQ-30)) was tested in a N-contaminated poison gas environment.

[0275] The calcined catalyst precursor was reduced at conditions as described in Example 51, cooled down to room temperature, suspended into molten wax and loaded in a CSTR under an inert gas blanket (argon or nitrogen).

[0276] The catalysts as described in Example 40 were tested for its slurry phase FTS performance in a laboratory micro slurry CSTR at a reactor temperature of 230° C. and a reactor pressure of about 17 bar and a total feed molar H.sub.2/CO ratio of about 1.63. The reactor was electrically heated and sufficiently high stirrer speeds were employed as to eliminate any gas-liquid mass transfer limitations. The feed gas space velocity was changed such that the syngas conversion was around 63%. The water partial pressure was less than 5 bar. The syngas feed contained 2000 vppb NH.sub.3.

Example 56—Slurry Phase Fischer-Tropsch Synthesis in NH.SUB.3 .Poison Gas (RCR Activation)

[0277] The catalyst as described in Example 40 was tested for its slurry phase FTS performance in a laboratory micro slurry CSTR at similar conditions as described in Example 55. However, the catalyst was activated as described in Example 52.

Example 57—Slurry Phase Fischer-Tropsch Synthesis in HCN Poison Gas

[0278] The catalyst as described in Example 40 was tested for its slurry phase FTS performance in a laboratory micro slurry CSTR at similar conditions as described in Example 55. However, the syngas feed contained about 2000 vppb HCN instead of 2000 vppb NH.sub.3.

[0279] Discussion

[0280] The FT rate and CH.sub.4 selectivity relative to the initial (day 3) FT rate and CH.sub.4 selectivity obtained over the catalyst as prepared in Example 40 under conditions as described in Example 55-57 are shown in Table 16.

TABLE-US-00016 TABLE 16 FT performance over Examples 40 with time on-line under conditions as described in Examples 55-57. Relative CH.sub.4 selectivity.sup.1 Time on-line, Example 55, Example 56, Example 56, days NH.sub.3, SR NH.sub.3, RCR HCN, SR 3 1.00 1.00 1.00 12 0.99 1.05 1.04 23 0.99 1.00 1.06 32 0.81 0.91 1.07 Relative FT rate.sup.2 Time on-line, Example 55, Example 56, Example 56, days NH.sub.3, SR NH.sub.3, RCR HCN, SR 3 1.00 1.00 1.00 12 0.89 1.08 0.89 23 0.77 0.95 0.87 32 0.82 0.96 0.83 .sup.1Drift in % CH.sub.4 selectivity relative to initial (day 3); C % excluding CO.sub.2 formation .sup.2Relative to the initial (day 3) FT rate ((CO + CO.sub.2) mol/CO/gs))

[0281] It can be concluded from Table 16 that the Co/Pt/MnTi—SiO.sub.2 (FSQ-30) catalyst also performed well under N-contaminated syngas conditions with no significant drift in the CH.sub.4 selectivity and no significant drift in the FT rates over time-on-line.