Catalysts

Abstract

A method of preparing a modified catalyst support comprises contacting a catalyst support material with a modifying component precursor in an impregnating liquid medium. The impregnating liquid medium comprises a mixture of water and an organic liquid solvent for the modifying component precursor. The mixture contains less than 17% by volume water based on the total volume of the impregnating liquid medium. The modifying component precursor comprises a compound of a modifying component selected from the group consisting of Si, Zr, Co, Ti, Cu, Zn, Mn, Ba, Ni, Al, Fe, V, Hf, Th, Ce, Ta, W, La and mixtures of two or more thereof. A modifying component containing catalyst support material is thus obtained. Optionally, the modifying component containing catalyst support material is calcined at a temperature above 100 C. to obtain a modified catalyst support.

Claims

1. A method of preparing a catalyst precursor, the method comprising contacting a catalyst support material with a modifying component precursor in an impregnating liquid medium wherein the impregnating liquid medium comprises a mixture of water and an organic liquid solvent for the modifying component precursor, which mixture contains at least 2.5% by volume water, but less than 12% by volume water based on the total volume of the impregnating liquid medium, the catalyst support material is selected from the group consisting of a catalyst support precursor which is convertible to a catalyst support upon calcination thereof, the catalyst support being in the form of a metal oxide which is an oxide of a metal selected from the group consisting of Al, Si, Ti, Mg, Zr and Zn; and a catalyst support selected from the group consisting of alumina in the form of one or more aluminium oxides, silica (SiO2), titania (TiO2), magnesia (MgO), zirconium oxide (ZrO2), zinc oxide (ZnO) and mixtures thereof; and the modifying component precursor comprises a compound of a modifying component selected from the group consisting of Si, Zr, Ti, Cu, Zn, Mn, Ba, Ni, Al, V, W, La and mixtures of two or more thereof, thereby to obtain a modifying component containing catalyst support material; optionally, calcining the modifying component containing catalyst support material at a temperature above 100 C. to obtain a modified catalyst support; and introducing a precursor compound of cobalt (Co) as an active catalyst component onto and/or into (i) the catalyst support material prior to contacting the catalyst support material with the modifying component precursor; (ii) the modifying component containing catalyst support material; and/or (iii) the modified catalyst support, thereby to obtain a catalyst precursor.

2. The method according to claim 1, wherein the modifying component containing catalyst support material is calcined at a temperature above 100 C. to obtain a calcined modified catalyst support, and wherein the precursor compound of the active catalyst component is introduced onto and/or into the calcined modified catalyst support.

3. A method of preparing a catalyst, which includes preparing a catalyst precursor using the method of claim 1; and reducing the catalyst precursor, thereby activating the catalyst precursor and obtaining the catalyst.

4. A hydrocarbon synthesis process which comprises preparing a catalyst using the method of claim 3; and contacting hydrogen with carbon monoxide at a temperature above 100 C. and a pressure of at least 10 bar with the catalyst so prepared, to produce hydrocarbons and, optionally, oxygenates of hydrocarbons.

5. The method according to claim 1, wherein the organic liquid solvent comprises a liquid organic compound which includes at least one heteroatom selected from oxygen or nitrogen.

6. The method according to claim 5, wherein the heteroatom of the liquid organic compound of the organic liquid solvent is oxygen, with the oxygen containing liquid organic compound being an alcohol.

7. The method according to claim 5 wherein the heteroatom of the liquid organic compound of the organic liquid solvent is nitrogen, with the nitrogen containing liquid organic compound being acetonitrile.

8. The method according to claim 1, wherein the impregnating liquid medium contains not more than 10% by volume water.

9. The method according to claim 6 wherein the liquid organic compound of the organic liquid solvent is ethanol.

10. The method according to claim 5 wherein the organic liquid solvent comprises a mixture of liquid organic compounds.

11. The method according to claim 1, wherein the modifying component precursor includes one or more organic groups bound to the modifying component.

12. The method according to claim 1, wherein, by contacting the catalyst support material with the modifying component precursor in the impregnating liquid medium, the modifying component precursor is thus introduced into and/or onto the catalyst support material by means of impregnation.

Description

(1) The invention will now be described in more detail with reference to the drawings and the following non-limiting examples:

(2) FIG. 1 shows, for Example 13, the Si-utilisation for Si modification of Puralox SCCa-2/150, as a function of the water concentration during the modification procedure;

(3) FIG. 2 depicts, for Example 13, the Delta D.sub.10 values as a function of the water concentration during the silicon modification procedure of the Puralox SCCa-5/150;

(4) FIG. 3 shows, for Example 14, the cumulative Al dissolution as a function of time for Si modified catalyst support materials not applying water addition, as well as applying water addition; and

(5) FIG. 4 shows, for Example 37, the cumulative Al dissolution as a function of time for the modified catalyst support materials of Examples, 12, 23, 24, 29 and 30.

EXAMPLES

Example 1

Inventive

(6) Gamma alumina Puralox SCCa-5/150 was modified with Si, using TEOS (tetra ethoxy silane) in a mixture of water and ethanol as an impregnating liquid medium. TEOS was added to the solvent mixture of ethanol and water (see Table 1) and stirred for 10 minutes at 60 C. Puralox SCCa-5/150 (50 g) was added to this mixture and stirred for another 10 minutes at 60 C. The impregnating liquid medium was slowly removed while gradually decreasing the pressure from atmospheric pressure to 80 mbar(a) and maintaining it at 80 mbar(a) until dryness, while the temperature was maintained at 60 C. By means of calcination at 510 C. for 2 hours in air, the resultant modifying component containing catalyst support material was thus converted to a calcined modified catalyst support.

Example 2

Inventive

(7) A modified catalyst support, as described in Example 1, was prepared, but with 2.5 vol % water in the total solvent mixture, i.e. in the impregnating liquid medium (see Table 1).

Example 3

Inventive

(8) A modified catalyst support, as described in Example 1, was prepared, but with 6 vol % water in the total solvent mixture (see Table 1).

Example 4

Inventive

(9) A modified catalyst support, as described in Example 1, was prepared, but with 7.5 vol % water in the total solvent mixture (see Table 1).

Example 5

Inventive

(10) A modified catalyst support, as described in Example 1, was prepared, but with 11 vol % water in the total solvent mixture (see Table 1).

Example 6

Comparative

(11) A modified catalyst support, as described in Example 1, was prepared, but with 17 vol % water in the total solvent mixture (see Table 1).

Example 7

Comparative

(12) A modified catalyst support, as described in Example 1, was prepared, but with 47 vol % water in the total solvent mixture (see Table 1).

Example 8

Comparative

(13) A modified catalyst support, as described in Example 1, was prepared, but with 96 vol % water in the total solvent mixture (see Table 1).

Example 9

Inventive

(14) A modified catalyst support, as described in Example 1, was prepared, but with 6 vol % water in the total solvent mixture (see Table 1).

Example 10

Comparative

(15) A modified catalyst support, as described in Example 1, was prepared, but using ethanol only as solvent (i.e. no water was used).

Example 11

Comparative

(16) A modified catalyst support, as described in Example 1, was prepared, but using water only as solvent (i.e. no ethanol was used).

Example 12

Comparative

(17) The gamma alumina Puralox SCCa-5/150, was not modified at all.

Example 13

(18) The silicon content of some of the modified catalyst supports was determined by means of ICP (Inductive Coupled Plasma) analysis. The silicon utilisation was calculated by dividing the silicon content as analysed by the silicon content that was aimed for, and multiplied by 100 (see results in Table 1 and FIG. 1).

(19) The D.sub.10 attrition index, a single impact test, was utilized to investigate the physical strength of the silica modified supports. The D.sub.10 attrition index is determined by using a Malvern Digisizer 2000. During analysis particles are impinged onto a steel plate and the amount of breakage gives an indication of the physical strength of the particles. 2.5 g of sample was used for each analysis. To determine the D.sub.10 value, two measurements are required, one at an air pressure setting of 0.15 bar and one at an air pressure setting of 3.0 bar. The D.sub.10 attrition index value is calculated by subtracting the D.sub.10 value at an air pressure of 3.0 bar from the D.sub.10 value at an air pressure of 0.15 bar (see results in Table 1 and FIG. 2). The D.sub.10 attrition index is an indication of the attrition resistancethe lower the value, the better is the attrition resistance.

(20) TABLE-US-00001 TABLE 1 Si-utilisation and Delta D.sub.10 Values of modified catalyst supports. Si- EtOH Water TEOS Target utilisation Delta Support name (ml) (vol %) (g) % Si (%).sup.a D.sub.10.sup.b Ex 1 50 0.4 8.05 2.1 80 2.7 (inventive) Ex 2 50 2.5 8.05 2.1 84 3.1 (inventive) Ex 3 50 6 7.2 1.95 97 3.2 (inventive) Ex 4 50 7.5 8.05 2.1 83 3.6 (inventive) Ex 5 50 11 8.05 2.1 85 4.5 (inventive) Ex 6 50 17 8.05 2.1 78 6.3 (comparative) Ex 7 26 47 7.2 1.95 97 6.3 (comparative) Ex 8 5 96 7.2 1.95 54 8 (comparative) Ex 9 50 6 8.05 2.1 87 4.5 (inventive) Ex 10 50 0 7.2 1.95 80 4.2 (comparative) Ex 11 0 100 8.05 2.1 27 11.2 (comparative) Ex 12 0 0 0 0 0 7.5 (comparative) .sup.aDetermined from ICP results .sup.bError 1 unit

(21) It was found that the addition of low amounts of water to the ethanol during the impregnation of TEOS onto the catalyst support material according to the present invention resulted in Si-utilisation of at least 80% and usually above the Si-utilisation of a support with no water addition during the support modification processsee FIG. 1 and Table 1.

(22) Furthermore, the addition of low amounts of water according to the present invention also resulted in improved Si-utilisation compared to examples where very high volumes of water (comparative Example 8 and Example 11) and not according to the present invention were used.

(23) Surprisingly, it was found that with the increased Si-utilisation, a consequence of the water addition to the support modification process, the physical strength or attrition resistance of the supports increased (despite the use of water during the modification process) as seen in the decrease in the Delta D.sub.10 values, indicating a lower tendency for break-up of the modified catalyst support (FIG. 2).

(24) However, the Delta D.sub.10 values of the modified catalyst support gradually increased with higher water content in excess of 11 vol %. At a water content of 17 vol % the Delta D.sub.10 values increased to D.sub.10=6.3, showing no attrition resistance benefits in modifying the catalyst support material with silica, as Puralox SCCa-5/150, exhibited D.sub.10=7.5. Thus the physical strength of the supports decreased showing higher tendency for break-up with increased water content at or above 17 vol %, as illustrated in FIG. 2. A further increase in water addition to 96% (Example 8) and using water only (Example 11) had a significant negative impact on the attrition resistance of the silica modified catalyst support, as can be seen from the high Delta D.sub.10, at 8 and 11 respectively. In the presence of excess water two distinct phases could be observed, due to the immiscible nature of the TEOS and the water.

Example 14

Conductivity Measurements

(25) 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.

(26) FIG. 3 shows the cumulative Al dissolution as a function of time for Si modified catalyst support materials not applying water addition (Example 10), as well as applying water addition (Example 5 and Example 9).

(27) It can be seen that the modified support material with no water addition, dissolved faster compared to the modified support material with the addition of water during the modification step.

Example 15

Inventive

(28) A modified catalyst support, as described in Example 1 was prepared. The water content in the total solvent mixture was 6 vol %, while the ethanol was replaced with ethyl acetate.

Example 16

Inventive

(29) A modified catalyst support, as described in Example 1 was prepared. The water content in the total solvent mixture was 6 vol %, while the ethanol was replaced with acetone.

Example 17

Inventive

(30) A modified catalyst support, as described in Example 1 was prepared. The water content in the total solvent mixture was 6 vol %, while the ethanol was replaced with acetonitrile.

Example 18

Inventive

(31) D.sub.10 attrition index values of the modified support samples with different organic solvents at 6 vol % water were determined (in the same manner as in Example 13) and are shown in Table 2.

(32) TABLE-US-00002 TABLE 2 The Delta D.sub.10 values of the modified catalyst supports prepared using different solvents. Solvent Water TEOS Target Delta Support name (50 ml) (vol %) (g) % Si D.sub.10.sup.a Ex 3 Ethanol 6 7.2 1.95 3.2 (inventive) Ex 15 Ethyl acetate 6 7.2 1.95 4.6 (inventive) Ex 16 Acetone 6 7.2 1.95 3.6 (inventive) Ex 17 Acetonitrile 6 7.2 1.95 4.8 (inventive) .sup.aError 1 unit

(33) As can be seen from Table 2, the change in solvent did not significantly influence the Delta D.sub.10 value of the modified catalyst support.

Example 19

Inventive

(34) Puralox SCCa-5/150 was evacuated to remove air from the pores. Onto this material, Puralox SCCa-5/150 (100 g), a mixture of water (1.43 ml), ethanol (28.6 ml) and TEOS (16.1 g) was impregnated (using the incipient wetness technique), targeting 6 vol % water and Si-loading of 2%. The mixture was stirred at 60 C. for 10 minutes until a free flowing powder was obtained. The resulting material was slowly dried by gradually decreasing the pressure from atmospheric pressure to 80 mbar(a) and maintaining it at 80 mbar(a), while the temperature was maintained at 60 C. By means of calcination at 510 C. for 2 hours in air, the catalyst support material was converted to a modified catalyst support.

(35) The Delta D.sub.10 attrition index values of the modified support samples using slurry and incipient wetness impregnation were determined (see Table 3).

(36) TABLE-US-00003 TABLE 3 The Delta D.sub.10 values of the modified catalyst supports prepared using slurry and incipient wetness impregnation. Solvent Water TEOS Target Delta Support name (ml) (vol %) (g) % Si D.sub.10.sup.a Ex 9 inventive 50 6 8.05 2.1 4.5 (slurry impregnation) Ex 19 Inventive 28.6 6 8.05 2.1 4.6 (incipient wetness impregnation) .sup.aError 1 unit

(37) The change in impregnation method did not influence the attrition resistance of the support, as indicated by the similar Delta D.sub.10 values for the modified catalyst supports.

Example 20

According to Invention

(38) A cobalt based Fischer-Tropsch synthesis catalyst precursor with the composition 30 gCo/0.075 gPt/100 gSupport was prepared on a modified catalyst support. The modified catalyst support was prepared as described in Example 1, with 5 vol % water in the total solvent mixture containing 1.6 wt % Si, with 90% Si-utilisation.

(39) The catalyst precursor was prepared as follows: In a first impregnation stage, Co(NO.sub.3).sub.2.6H.sub.2O (39.5 g) and [Pt(NH.sub.4).sub.4(NO.sub.3).sub.2] (0.0248 g) were dissolved in 50 ml of distilled water. To the mixture, 50 g of the Si-modified support was added and the water was driven off by adopting the drying profile shown in Table 4. Once dry, the sample was calcined at 250 C. using a fluidised bed with a flow of air for 6 hours. Then, in a second impregnation stage, the above steps were repeated using Co(NO.sub.3).sub.2.6H.sub.2O (28.4 g) and [Pt(NH.sub.4).sub.4(NO.sub.3).sub.2] (0.0407 g) dissolved in 50 ml of distilled water, and to which 50 g of the calcined material from the first impregnation stage were added; thereafter, a similar drying profile as tabled in Table 4 below was adopted to dry the sample. The dry material was then calcined at 250 C. for another 6 hours in the same manner as for the first impregnation stage.

(40) TABLE-US-00004 TABLE 4 Pressure/mbar Temperature/ C. Duration/min Atm 60 10 260 60 30 260 75 90 260 85 60 50 85 180

Example 21

Comparative

(41) A cobalt based Fischer-Tropsch synthesis catalyst precursor was prepared in the same manner as in Example 20, however, onto the modified catalyst support according to Example 10.

Example 22

(42) Cobalt catalyst precursors of Examples 20 and 21 were reduced prior to Fischer-Tropsch synthesis in a tubular reactor at a hydrogen space velocity of 200 ml.sub.nhydrogen/g.sub.catalysth and atmospheric pressure. The temperature was increased to 425 C. at 1 C./min, after which isothermal conditions were maintained for 16 hours.

(43) Between 10 g and 30 g of the resultant reduced catalyst, ranging between 38 m to 150 m, was suspended in 300 ml molten wax and loaded in a CSTR with an internal volume of 500 ml, under a nitrogen blanket.

(44) The pressure was increased to 18 bar and the temperature to 230 C., where after the synthesis was introduced. The synthesis feed gas consisted of hydrogen and carbon monoxide, and contained 10% argon as an internal standard. This reactor was electrically heated and sufficiently high stirrer speeds were employed so as to eliminate any gas-liquid mass transfer limitations. The feed flow was controlled by means of Brooks mass flow controllers, and space velocities ranging from 2 and 4 m.sup.3.sub.n/kg.sub.catalysth were used.

(45) Further details about the experimental conditions for the Fischer-Tropsch synthesis process and the FT performance after 8 days on-line are presented in Table 5.

(46) TABLE-US-00005 TABLE 5 The experimental conditions for the Fischer-Tropsch synthesis process and the FT performance after 8 days on-line. Ex 20 Ex 21 (inventive) (comparative) Modified catalyst support 5 vol % water, No water, targeted 1.7 wt % Si, targeted 1.95 wt % Si, containing 1.6 wt % containing 1.6 wt % Si, 90% Si-utilisation. Si, 80% Si-utilisation Time on-line (days) 8 8 Reactor pressure (bar) 18.1 18.4 Reactor temperature 230 230 ( C.) Clean syngas with 1.6 1.6 H.sub.2/CO-ratio Reactor Partial Pressures (bar) H.sub.2 4.7 4.8 CO 3.9 4.2 H.sub.2O 4.3 4.3 Syngas conversion (%) 61 60 Activity 1.0 1.0 (relative to example 21) CH.sub.4 selectivity 6.1 6.2 (C-atom %)

(47) It can be seen from Table 5 that the Fischer-Tropsch performance of the catalyst containing the TEOS/ethanol/water modified catalyst support (Example 20) is comparable to the catalyst containing the TEOS/ethanol modified catalyst support (Example 21). Due to the increased silicon utilisation, a consequence of the water addition, the targeted TEOS was lowered, i.e. less TEOS was added, to effect similar Si loadings, which in-turn did not negatively influence FT performance of the catalyst.

(48) In general, the examples have thus shown that support modification can be improved by using water/organic solvent mixtures with not more than 20% water, which improved the mechanical strength and the Si utilisation of the support, without affecting the FT performance.

Example 23

Comparative

(49) Gamma alumina Puralox SCCa-150 (B31624) was modified with Ti, using Ti(O.sup.tBu).sub.4 (titanium tetrabutoxide) dissolved in a solvent mixture (impregnating liquid medium) of ethanol and 19 vol % acetic acid. Ti(O.sup.tBu).sub.4 was added to the solvent mixture (see Table 6) and stirred for 10 minutes at 60 C. Puralox SCCa-150 (B31634) was added to this mixture and stirred for another 10 minutes at 60 C. The solvent mixture was slowly removed with a gradual decrease of the pressure from atmospheric pressure to 80 mbar and maintaining it at 80 mbar until dryness, while the temperature was maintained at 60 C. By means of calcination at 550 C. for 2 hours in air, the resultant modifying component containing catalyst support material was thus converted to a calcined modified catalyst support.

Example 24

Inventive

(50) A modified catalyst support as described in Example 23, was prepared, but with 5 vol % water in the total solvent mixture, i.e. in the impregnating liquid medium which thus comprised ethanol, acetic acid and water (see Table 6).

Example 25

Comparative

(51) A modified catalyst support as described in Example 23, was prepared, but with TEOS (tetraethoxy silane) instead of Ti(O.sup.tBu).sub.4 as the modifying agent (see Table 6).

Example 26

Inventive

(52) A modified catalyst support as described in Example 25, was prepared, but with 5 vol % water in the total solvent mixture, i.e. in the impregnating liquid medium which thus comprised ethanol, acetic acid and water (see Table 6).

Example 27

Comparative

(53) A modified catalyst support as described in Example 23, was prepared, but with Zr(O.sup.iPr).sub.3 (zirconium isopropoxide) instead of Ti(O.sup.tBu).sub.4 as the modifying agent (see Table 6).

Example 28

Inventive

(54) A modified catalyst support as described in Example 27, was prepared, but with 10 vol % water in the total solvent mixture i.e. in the impregnating liquid medium which thus comprised ethanol, acetic acid and water (see Table 6).

Example 29

Comparative

(55) A modified catalyst support as described in Example 25, was prepared, but no post impregnation calcination step was performed (see Table 6).

Example 30

Inventive

(56) A modified catalyst support as described in Example 29, was prepared, but with 5 vol % water in the total solvent mixture i.e. in the impregnating liquid medium which thus comprised ethanol, acetic acid and water (see Table 6).

Example 31

Comparative

(57) Pural (boehmite phase alumina) was modified with Si, using TEOS (silicon tetraorthosilicate) in ethanol as an impregnating liquid medium. TEOS was added to the ethanol (see Table 6) and stirred for 10 minutes at 60 C. Pural was added to this mixture and stirred for another 10 minutes at 60 C. The solvent was slowly removed with a gradual decrease in the pressure from atmospheric pressure to 80 mbar and maintaining it at 80 mbar until dryness, while the temperature was maintained at 60 C. By means of calcination at 550 C. for 2 hours in air, the modifying component containing catalyst support material was thus converted to a calcined modified catalyst support (Table 6).

Example 32

Inventive

(58) A modified catalyst support as described in Example 31, was prepared, but with 5 vol % water in a solvent mixture of ethanol and water i.e. in an impregnating liquid medium which thus comprised ethanol and water (see Table 6).

Example 33

Comparative

(59) Pural (boehmite phase alumina) was calcined at 550 C. for 2 hours and was not modified at all.

Example 34

Comparative

(60) Titania (spray dried and calcined at 550 C. for 2 hours) was modified with Si, using TEOS (silicon tetraorthosilicate) dissolved in ethanol. TEOS was added to the ethanol (see Table 6) and stirred for 10 minutes at 60 C. Titania was added to this mixture and stirred for another 10 minutes at 60 C. The solvent was slowly removed with a gradual decrease in the pressure from atmospheric pressure to 80 mbar and maintaining it at 80 mbar until dryness, while the temperature was maintained at 60 C. By means of calcination at 550 C. for 2 hours in air, the modifying component containing catalyst support material was thus converted to a calcined modified catalyst support (see Table 6).

Example 35

Inventive

(61) A modified catalyst support as described in Example 34, was prepared, but with 19 vol % acetic acid and 5 vol % water in the total solvent mixture, i.e. in an impregnating liquid medium which thus comprised ethanol, acetic acid and water (see Table 6).

Example 36

Comparative

(62) Titania (spray dried and calcined at 550 C. for 2 hours), was not modified at all.

(63) TABLE-US-00006 TABLE 6 Target M- Delta Water wt % utilisation D.sub.10 Example Support (vol %) Metal M (%) (m) Ex 23 Al.sub.2O.sub.3 0 Ti 2.6 84 5.8 (comparative) Ex 24 Al.sub.2O.sub.3 5 Ti 2.6 89 4.0 (inventive) Ex 25 Al.sub.2O.sub.3 0 Si 1.6 70 3.8 (comparative) Ex 26 Al.sub.2O.sub.3 5 Si 1.6 83 3.2 (inventive) Ex 27 Al.sub.2O.sub.3 0 Zr 2.6 99 7.5 (comparative) Ex 28 Al.sub.2O.sub.3 10 Zr 2.6 99 4.9 (inventive) Ex 29 Al.sub.2O.sub.3 0 Si 1.6 84 5.2 (comparative) Ex 30 Al.sub.2O.sub.3 5 Si 1.6 99 3.1 (inventive) Ex 31 boehmite 0 Si 2.4 81 8.5 (comparative) Ex 32 boehmite 5 Si 2.4 87 6.2 (inventive) Ex 33 boehmite 10.5 (comparative) Ex 34 TiO.sub.2 0 Si 1.6 80 1.5 (comparative) Ex 35 TiO.sub.2 5 Si 1.6 92 1.0 (inventive) Ex 36 TiO.sub.2 7.1 (comparative)

(64) The metal utilization and the delta D10 values were determined in the same manner as described in Example 13

Example 37

(65) The cumulative Al dissolution as a function of time was tested as per procedures of Example 14 for samples from Examples 12, 23, 24, 29 and 30 (see FIG. 4).

Example 38

Comparative

(66) A cobalt catalyst precursor was prepared in the same manner as described in Example 20, except that the support of Example 23 was used.

Example 39

Inventive

(67) A cobalt catalyst precursor was prepared in the same manner as described in Example 20, except that the support of Example 24 was used.

Example 40

Comparative

(68) A cobalt catalyst precursor was prepared in the same manner as described in Example 20, except that the support of Example 12 was used. TEOS modification, using the procedure according to Example 25, was performed, except that no calcination at 550 C. was executed.

Example 41

Inventive

(69) A cobalt catalyst precursor was prepared in the same manner as described in Example 20, except that the support of Example 12 was used. TEOS modification, using the procedure according to Example 26, was performed, except that no calcination at 550 C. was executed.

(70) TABLE-US-00007 TABLE 7 Water (vol %) Metal Target wt % Delta used during used for of support D.sub.10 of Al support support modifying catalyst leaching Example Support modification modification metal (m) (ppm) Ex 38 Al.sub.2O.sub.3 0 Ti 2.6 4.7 89 (comparative) Ex 39 Al.sub.2O.sub.3 5 Ti 2.6 3.0 11 (inventive) Ex 40 Al.sub.2O.sub.3 0 Si 1.6 4.6 58 (comparative) Ex 41 Al.sub.2O.sub.3 5 Si 1.6 3.0 19 (inventive)